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Flatten layers affinity designer 自由. Saitama University Research Directory
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Manage Settings Continue with Recommended Cookies. Despite all of the differences between the various graphic design applications that exist in the world, one of the things they all have in common is that they handle layers and layer merging in a relatively similar way. Merging layers with Affinity Designer is complicated though, because Designer handles layers in a fundamentally different way.
Before we begin going over how to merge layers in Affinity Designer, we first need to have an understanding of the three different types of layers that exist in Affinity Designer.
Vector layers exist in the Designer Persona. Every time you create an object in the Designer persona, it is placed on its own vector layer:. Contrary to how other vector design applications work, each vector object that you create can only exist on its own layer.
There is no way to merge vector layers together so that multiple objects can exist on one vector layer unless you combine them into a single object via Boolean operations. Vector layers can be grouped together into layer groups , but they cannot be merged.
For them to exist together on a single layer, as would be the case in other applications, would require you to create layer groups with them. What you think of as a layer in other applications is really just a layer group in Affinity Designer. Pixel layers exist in the Pixel Persona.
Every time you generate a pixel drawing using one of the tools in the Pixel Persona, it will be placed on its own pixel layer. Pixel layers function in a slightly different way than vector layers do, mainly because of the fundamental differences in how vectors and pixels are created.
You can indeed create multiple pixel-based drawings and designs on a single pixel layer by adding to the existing layer. Finally, there are Adjustment Layers. Adjustment layers allow you to change the appearance of an object in a non-destructive way that can easily be undone. The benefit of using an adjustment layer is that it can easily be deleted, allowing your photo to have color again.
Adjustment layers can also be applied to multiple layers and objects, applying the black and white effect to all of them. Adjustment layers can be added to vector layers or to pixel layers, and in either the Designer or Pixel persona. Much like vector layers and pixel layers, adjustment layers cannot be merged.
They can, however, be segmented into layer groups. Despite the unique nature of how layers work in Affinity Designer, we still have a problem to address.
Therefore, if you want to organize your artwork using layers, you must place the layers into layer groups. To place your vector layers into layer groups, hold Shift on your keyboard and click each layer in order to select them all. You may have to rearrange the position of your layers accordingly. This can be done by simply clicking and dragging them into the desired position. The group will then function in the same ways that an individual layer would function, making it easy to organize your work.
And unlike merging, layer groups are non-destructive and can be undone at any time. Much like merging vector layers, you can segment pixel layers into groups. Now, group them together by right-clicking them and selecting Group from the dropdown menu:. This will rasterize the entire group, turning your group of pixel layers into a single pixel layer, effectively merging them:.
It would be nice if Affinity added a shortcut that combines both of these actions so that it could be done directly, but regardless, this workaround is just as effective as a traditional merge function for pixel layers anyway.
Next, right-click on the layers and select Group from the dropdown menu. This will place your adjustment layers into a layer group:. Seeing as how layer groups can be just as effective as merging layers in Affinity Designer, you could make the argument that layer merging is an outdated concept, and that Affinity is being innovative and forward-looking by doing away with it. However, when layers are merged in the traditional sense, the change is permanent. There is one downside to this approach though, mainly in regards to vector layer groups.
When grouped together, the vector objects will no longer be editable independent of each other. They will have to be released from the group in order to do so.
If you have any questions, or if any part of this lesson was unclear, simply leave a comment below. Want to learn more about how Affinity Designer works? Enroll Now. Want to learn more about how Adobe Illustrator works?
Check out my Illustrator Explainer Series - a comprehensive collection of over videos where I go over every tool, feature and function and explain what it is, how it works, and why it's useful. This post may contain affiliate links. Read affiliate disclosure here. If pixel layers need to be rasterized to group, what the heck are they before rasterizing?
Glad you like the content though. To edit a vector object in a group just double click it. All items in a group are then editable individually until you collapse the group again. No need to release any of the objects from the group. Your email address will not be published. Save my name and email in this browser for the next time I comment. When creating artwork it is sometimes required that we preserve areas of transparency in the finished design.
Turning off the visibility of the background layer is a good start as it creates a Transforming shapes and objects is at the heart of what vector design is all about. One of the many ways you may seek to transform an object, however, is by slicing and cutting it into pieces.
Vendor List Privacy Policy. Skip to content. com is an educational media platform for learning about graphic design software. Leave a Reply Cancel reply Your email address will not be published. Read More. There is no way to directly merge vector layers in Affinity Designer.
Instead, you must segment them into layer groups. There is no way to directly merge adjustment layers in Affinity Designer. Become A Master of Affinity Designer! Become A Master of Adobe Illustrator!
Flatten layers affinity designer 自由
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The current study opens up a new synthetic route for controllable growth of 2D layered metallic materials, which is of great importance in study of rich physics in 2D metals, as well as in search for novel 2D superconductors. Efficient preparation of graphene liquid cell utilizing direct transfer with large-area well-stitched graphene Reviewed.
Yuki Sasaki, Ryo Kitaura, Jong Min Yuk, Alex Zettl, Hisanori Shinohara. CHEMICAL PHYSICS LETTERS Vol. Language： Japanese Publishing type： Research paper scientific journal Publisher： ELSEVIER SCIENCE BV.
By utilizing graphene-sandwiched structures recently developed in this laboratory, we are able to visualize small droplets of liquids in nanometer scale.
We have found that small water droplets as small as several tens of nanometers sandwiched by two single-layer graphene are frequently observed by TEM. Due to the electron beam irradiation during the TEM observation, these sandwiched droplets are frequently moving from one place to another and are subjected to create small bubbles inside.
The synthesis of a large area single-domain graphene of high-quality is essential to prepare the graphene sandwiched cell which safely encapsulates the droplets in nanometer size. C Elsevier B. Importance of Three-Body Interactions in Molecular Dynamics Simulations of Water Demonstrated with the Fragment Molecular Orbital Method.
Pruitt SR, Nakata H, Nagata T, Mayes M, Alexeev Y, Fletcher G, Fedorov DG, Kitaura K, Gordon MS. Journal of chemical theory and computation Vol. Possible Immune Regulation of Natural Killer T Cells in a Murine Model of Metal Ion-Induced Allergic Contact Dermatitis.
Kumagai K, Horikawa T, Shigematsu H, Matsubara R, Kitaura K, Eguchi T, Kobayashi H, Nakasone Y, Sato K, Yamada H, Suzuki S, Hamada Y, Suzuki R. Isolation and Structure Determination of a Missing Endohedral Fullerene La C through In Situ Trifluoromethylation Reviewed International journal. Zhiyong Wang, Shinobu Aoyagi, Haruka Omachi, Ryo Kitaura, Hisanori Shinohara. D-5h-symmetric fullerene C D-5h-C is one of the most abundant members of the fullerene family. One longstanding mystery in the field of fullerene chemistry is whether D-5h-C is capable of accommodating a rare-earth metal atom to form an endohedral metallofullerene M D-5h-C, which would be expected to show novel electronic properties.
The molecular structure of La C remains unresolved since its discovery three decades ago because of its extremely high instability under ambient conditions and insolubility in organic solvents. Herein, we report the single-crystal X-ray structure of La C CF3 3 , which was obtained through in situ exohedral functionalization by means of trifluoromethylation. The X-ray crystallographic study reveals that La C CF3 3 is the first example of an endohedral rare-earth fullerene based on D5hC The dramatically enhanced stability of La C CF3 3 compared to La C can be ascribed to trifluoromethylationinduced bandgap enlargement.
Single atom spectroscopy: Decreased scattering delocalization at high energy losses, effects of atomic movement and X-ray fluorescence yield Reviewed International journal. Luiz H. Tizei, Yoko Iizumi, Toshiya Okazaki, Ryo Nakanishi, Ryo Kitaura, Hisanori Shinohara, Kazu Suenaga. Language： English Publishing type： Research paper scientific journal Publisher： ELSEVIER.
Single atom localization and identification is crucial in understanding effects which depend on the specific local environment of atoms. In advanced nanometer scale materials, the characteristics of individual atoms may play an important role. Here, we describe spectroscopic experiments electron energy loss spectroscopy, EELS, and Energy Dispersed X-ray spectroscopy, EDX using a low voltage transmission electron microscope designed towards single atom analysis.
For EELS, we discuss the advantages of using lower primary electron energy 30 keV and 60 keV and higher energy losses above eV. The effect of atomic movement is considered. Finally, we discuss the possibility of using atomically resolved EELS and EDX data to measure the fluorescence yield for X-ray emission. C Elsevier BY. Chemical Vapor Deposition Growth of Graphene and Related Materials.
Ryo Kitaura, Yasumitsu Miyata, Rong Xiang, James Hone, Jing Kong, Rodney S. Ruoff, Shigeo Maruyama. JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN Vol. Language： Japanese Publishing type： Research paper scientific journal Publisher： PHYSICAL SOC JAPAN. Research on atomic layers including graphene, hexagonal boron nitride hBN , transition metal dichalcogenides TMDCs and their heterostructures has attracted a great deal of attention.
Chemical vapor deposition CVD can provide large-area structure-defined high-quality atomic layer samples, which have considerably contributed to the recent advancement of atomic-layer research. Kitaura Ryo, Miyata Yasumitsu, Xiang Rong, Hone James, Kong Jing, Ruoff Rodney S. Journal of the Physical Society of Japan Vol. Publishing type： Research paper scientific journal Publisher： Physical Society of Japan.
Template Synthesis of Linear-Chain Nanodiamonds Inside Carbon Nanotubes from Bridgehead-Halogenated Diamantane Precursors. Reviewed International journal.
Yusuke Nakanishi, Haruka Omachi, Natalie A Fokina, Peter R Schreiner, Ryo Kitaura, Jeremy E P Dahl, Robert M K Carlson, Hisanori Shinohara. Angewandte Chemie International ed. in English Vol. Publishing type： Research paper scientific journal Publisher： WILEY-V C H VERLAG GMBH. A simple method for the synthesis of linear-chain diamond-like nanomaterials, so-called diamantane polymers, is described. This synthetic approach is primarily based on a template reaction of dihalogen-substituted diamantane precursors in the hollow cavities of carbon nanotubes.
Under high vacuum and in the presence of Fe nanocatalyst particles, the dehalogenated radical intermediates spontaneously form linear polymer chains within the carbon nanotubes. Transmission electron microscopy reveals the formation of well-aligned linear polymers.
We expect that the present template-based approach will enable the synthesis of a diverse range of linear-chain polymers by choosing various precursor molecules. The present technique may offer a new strategy for the design and synthesis of one-dimensional nanomaterials.
Core-level spectroscopy to probe the oxidation state of single europium atoms. Luiz H G Tizei, Ryo Nakanishi, Ryo Kitaura, Hisanori Shinohara, Kazu Suenaga. Physical review letters Vol. The valence of individual europium atoms confined in carbon nanotubes is successfully measured by using core-level electron energy loss spectroscopy.
Changes in the oxidation state at the atomic scale have been observed in Eu atomic chains exposed to oxygen. This indicates that single atoms change their valence state multiple times during the reaction, suggesting that oxidation in confined spaces and with extra energy input from the electron beam might not be a simple one step electron transfer event. Fabrication and optical probing of highly extended, ultrathin graphene nanoribbons in carbon nanotubes.
Hong En Lim, Yasumitsu Miyata, Miho Fujihara, Susumu Okada, Zheng Liu, Arifin, Kayoko Sato, Haruka Omachi, Ryo Kitaura, Stephan Irle, Kazu Suenaga, Hisanori Shinohara. Nanotemplated growth of graphene nanoribbons GNRs inside carbon nanotubes is a promising mean to fabricate ultrathin ribbons with desired side edge configuration.
We report the optical properties of the GNRs formed in single-wall carbon nanotubes. Their optical responses are probed through the diazonium-based side-wall functionalization, which effectively suppresses the excitonic absorption peaks of the nanotubes without damaging the inner GNRs.
Differential absorption spectra clearly show two distinct peaks around 1. These peaks are assigned to the optical transitions between the van Hove singularities in the density of state of the GNRs in qualitative agreement with the first-principles calculations. Resonance Raman spectra and transmission electron microscope observations also support the formation of long GNRs. Minimal inflammogenicity of pristine single-wall carbon nanotubes. Shinya Toyokuni, L I Jiang, Ryo Kitaura, Hisanori Shinohara.
Nagoya journal of medical science Vol. Carbon nanotubes CNTs are a novel synthetic material comprising only carbon atoms. Based on its rigidity, its electrical and heat conductivity and its applicability to surface manufacturing, this material is expected to have numerous applications in industry. However, due to the material's dimensional similarity to asbestos fibers, its carcinogenicity was hypothesized during the last decade, and indeed, we have shown that multi-wall CNTs MWCNTs of 50 nm in diameter are potently carcinogenic to mesothelial cells after intraperitoneal injection.
Additionally, we suggested that inflammogenicity after intraperitoneal injection can predict mesothelial carcinogenesis. However, few data have been published on the intraperitoneal inflammogenicity of single-wall CNTs SWCNTs. Here, we conducted a series of studies on SWCNTs using both intraperitoneal injection into rats and MeT5A mesothelial cells.
MWCNTs of 50 nm in diameter were used as a positive control, and tangled MWCNTs of 15 nm in diameter were used as a negative control. The results suggest that SWCNTs are a low-risk material with respect to mesothelial carcinogenesis. Toyokuni S, Jiang LI, Kitaura R, Shinohara H.
Shinya Toyokuni, Li Jiang, Ryo Kitaura, Hisanori Shinohara. NAGOYA JOURNAL OF MEDICAL SCIENCE Vol. Language： English Publishing type： Research paper scientific journal Publisher： NAGOYA UNIV, SCH MED. However, due to the material's dimensional similarity to asbestos fibers, its carcinogenicity was hypothesized during the last decade, and indeed, we have shown that multi- wall CNTs MWCNTs of 50 nm in diameter are potently carcinogenic to mesothelial cells after intraperitoneal injection.
The results suggest that SWCNTs are a low- risk material with respect to mesothelial carcinogenesis. Toyokuni Shinya, Jiang Li, Kitaura Ryo, Shinohara Hisanori. Comparison of the acute effects of right ventricular apical pacing and biventricular pacing in patients with heart failure. Kanzaki H, Satomi K, Noda T, Shimizu W, Kamakura S, Kitaura Y, Ishizaka N, Kitakaze M. Internal medicine Tokyo, Japan Vol. Synthesis and TEM structural characterization of Cflattened carbon nanotube nanopeapods Reviewed.
Qing Wang, Ryo Kitaura, Yuta Yamamoto, Shigeo Arai, Hisanori Shinohara. NANO RESEARCH Vol. Language： Japanese Publishing type： Research paper scientific journal Publisher： TSINGHUA UNIV PRESS. A fully flattened carbon nanotube FNT , a graphene nanoribbon GNR analogue, provides a hollow space at edges for endohedral doping. Due to the unique shape of the hollow space of FNTs, novel types of low-dimensional arrangements of atoms and molecules can be obtained through endohedral doping into FNTs, which provides a new type of nanopeapods.
FNT-based nanopeapods have been synthesized through endohedral doping of C, and their structural characterization with transmission electron microscopy TEM performed. The doping of C into the inner hollow space of FNTs has been carried out via the gas-phase filling method, where open-ended FNTs are sealed in a glass ampoule and heated at K for two days.
TEM observations show that most of the encapsulated C molecules align as single molecular chains along the edges of FNTs and that some of the C forms two-dimensional close-packed structures inside FNTs. Drastic Change in Photoluminescence Properties of Graphene Quantum Dots by Chromatographic Separation. Naoto Fuyuno, Daichi Kozawa, Yuhei Miyauchi, Shinichiro Mouri, Ryo Kitaura, Hisanori Shinohara, Toku Yasuda, Naoki Komatsu, Kazunari Matsuda.
ADVANCED OPTICAL MATERIALS Vol. Graphene quantum dots GQDs have attracted a great deal of interest from the viewpoints of both fundamental studies and applications. Photoluminescence PL is one of the intriguing properties of GQDs, however, the mechanism of the PL in GQDs is not fully understood. In the present study, a drastic change in the PL from UV to red light region is reported among GQDs separated by size-exclusion high performance liquid chromatography.
It is confirmed by transmission electron microscopy images that the GQDs are separated by the difference in their overall sizes. Two-dimensional PL excitation spectra of the chromatographically separated GQDs show four distinct emission peaks at approximate to , approximate to , approximate to , and approximate to nm.
The dominant luminescence features of the separated GQDs show discrete changes depending on the overall size of GQDs, indicating that the PL variation occurs because of differences in density, shape, and size of sp 2 fragments available in the GQDs.
Rayleigh scattering studies on inter-layer interactions in structure-defined individual double-wall carbon nanotubes. Zhao SH. NANO RESEARCH page： Rayleigh scattering studies on inter-layer interactions in structure-defined individual double-wall carbon nanotubes Reviewed. Sihan Zhao, Tomoya Kitagawa, Yuhei Miyauchi, Kazunari Matsuda, Hisanori Shinohara, Ryo Kitaura.
Although the inter-layer coupling in layered materials has attracted considerable interest due to its importance in determining physical properties of two-dimensional systems, studies on the inter-layer coupling in one-dimensional systems have so far been limited.
Double-wall carbon nanotubes DWCNTs are one of the most fundamental and ideal model systems to study the inter-layer coupling in one-dimensional systems. In this work, Rayleigh scattering spectroscopy and transmission electron microscopy are used to characterize the electronic transition between inner-and outer-nanotubes of the exactly same individual DWCNT.
We find that the inter-layer coupling is strong, leading to downshifts in most of the optical transition energies up to similar to 0.
We also find that the presence of metallic tubes lead to stronger shifts. The inter-layer screening of Coulomb interactions is one of the key factors in explaining the observed results. Zhiyong Wang, Ryo Kitaura, Hisanori Shinohara. The unstable fullerene I-h-C can be stabilized greatly by encapsulation of two rare-earth metal atoms in its interior. Density functional calculations demonstrate that La-2 I-h,-C has a closed-shell configuration, whereas Y-2 l h -C has a triplet ground state.
Unlike La-2 I-h,-C with a high stability, Y-2 l h -C is found to be a highly reactive radical due to the unpaired electron distributed on the fullerene cage. Such characteristic properties of La-2 I-h,-C and Y-2 l h -C originate from the different energy levels of the metal-based molecular orbitals. Y-2 l h -C can be stabilized, however, through exterior functionalization with a CF3 group.
Interestingly, metallofullerenes Gd-2 I-h,-C and Lu-2 I-h,-C have similar frontier molecular orbitals and chemical stabilities to those of Y-2 I-h,-C Direct observation of zipper-like wall-to-wall coalescence of double-wall carbon nanotubes Reviewed.
Sihan Zhao, Yasumitsu Miyata, Hisanori Shinohara, Ryo Kitaura. CARBON Vol. Language： Japanese Publishing type： Research paper scientific journal Publisher： PERGAMON-ELSEVIER SCIENCE LTD. In situ transmission electron microscope TEM observation has become a fairly powerful characterization method to uniquely provide the real-time information on the dynamics and kinetics of physical and chemical transformations at the nanometer scale.
Here, we report a development of a high-temperature-compatible specimen heating holder equipped with a micro-sized carbon nanotube CNT network heater. This has directly led to a real-time imaging of a purely thermally-driven nano-welding process between two parallel-aligned double-wall carbon nanotubes DWCNTs using low-voltage TEM 80 keV ; a single larger-diameter DWCNT was formed after the reaction and the reaction rate was determined.
C Elsevier Ltd. Microporous structures having phenylene fin: Significance of substituent groups for rotational linkers in coordination polymers Reviewed. Ryotaro Matsuda, Wataru Kosaka, Ryo Kitaura, Yoshiki Kubota, Masaki Takata, Susumu Kitagawa. Language： English Publishing type： Research paper scientific journal Publisher： ELSEVIER SCIENCE BV. Microporous coordination polymers having various shaped apertures were synthesized and crystallographically characterized using substituted terephthalate ligands.
The substituents exert a notable influence on the channel size and shape depending on the orientations and disordering of the phenylene units such as a fin. This is a new aspect of porous coordination polymers, which would provide important information for a precise design of the micropore.
C Elsevier Inc. Structure of Tm-2 and Tm2C2 encapsulated in low-symmetry C C-s 6 fullerene cage by single crystal X-ray diffraction Reviewed.
Yuki Sado, Shinobu Aoyagi, Noriko Izumi, Ryo Kitaura, Tim Kowalczyk, Jian Wang, Stephan Irle, Eiji Nishibori, Kunihisa Sugimoto, Hisanori Shinohara. Publishing type： Research paper scientific journal Publisher： ELSEVIER SCIENCE BV. The molecular structures of Tm-2 C C-s 6 and Tm2C2 C C-s 6 are determined by means of single crystal X-ray diffraction using the co-crystals with nickel octaethylporphyrin Ni OEP. The molecular orientations and Tm positions of Tm-2 C C-s 6 and Tm2C2 C C-s 6 are basically the same each other.
One of the two Tm positions is very close to the Tm position of Tm C C-s 6. These facts demonstrate that the stable endohedral Tm positions are not fundamentally affected by the addition of the other Tm atoms but dependent on the kind of the fullerene cage structure. Size-selective complexation and extraction of endohedral metallofullerenes with cycloparaphenylene.
Yusuke Nakanishi, Haruka Omachi, Sanae Matsuura, Yasumitsu Miyata, Ryo Kitaura, Yasutomo Segawa, Kenichiro Itami, Hisanori Shinohara. A new strategy for the non-chromatographic extraction of metallofullerenes from solutions of arc-processed raw soot is based on the size-selective complexation with cycloparaphenylene CPP. This approach should open new opportunities in metallofullerene chemistry, including for the bulk extraction of metallofullerenes.
Kobayashi Keita, Kitaura Ryo, Sasaki Katsuhiro, Kuroda Kotaro, Saito Takeshi, Shinohara Hisanori. Language： Japanese Publishing type： Research paper scientific journal Publisher： The Japan Institute of Metals and Materials. The AuNW drifts significantly within the SWCNT during the reduction.
Metal catalyst-free mist flow chemical vapor deposition growth of single-wall carbon nanotubes using C colloidal solutions Reviewed.
Yun Sun, Ryo Kitaura, Jinying Zhang, Yasumitsu Miyata, Hisanori Shinohara. Metal catalyst-free mist flow chemical vapor deposition CVD growth of single-walled carbon nanotubes SWCNTs with C fullerenes has been investigated by using an aqueous colloidal C solution.
Under the optimum reaction condition, relatively uniform SWCNTs with a mean diameter of 1. Cap opening, nucleation and the growth of SWCNTs have been occurring almost simultaneously during the present CVD.
C can be used as the seeds i. Furthermore, the coalescence of C caps into a larger one leads to the growth of SWCNTs with larger diameters. Synthesis of refractory conductive niobium carbide nanowires within the inner space of carbon nanotube templates Reviewed. Keita Kobayashi, Ryo Kitaura, Qing Wang, Ikuya Wakamori, Hisanori Shinohara, Satoshi Anada, Takeshi Nagase, Takeshi Saito, Masaharu Kiyomiya, Hidehiro Yasuda.
Conductive niobium carbide NbC nanowires with diameters of nm were synthesized within the inner space of carbon nanotubes CNTs by exposing the CNTs to niobium V chloride vapor through hydrogen reduction. The NbC nanowires were found to have a NaCl-type crystal structure by transmission electron microscopy and transmission electron diffractometry. Results from electronic transport measurements imply that the electrical conductivity of the synthesized product was improved compared with that of empty CNTs.
A cubic dipole lattice of water molecules trapped inside carbon cages. Shinobu Aoyagi, Norihisa Hoshino, Tomoyuki Akutagawa, Yuki Sado, Ryo Kitaura, Hisanori Shinohara, Kunihisa Sugimoto, Rui Zhang, Yasujiro Murata. Chemical communications Cambridge, England Vol. Publishing type： Research paper scientific journal Publisher： ROYAL SOC CHEMISTRY.
We report the crystal structure and dielectric properties of a pure H2O C60 crystal at low temperature. The caged water molecules free from the hydrogen bonds rotate even at 8 K. The antifreeze rotating water molecules respond to an external electric field due to their permanent dipole moment. Observation and Characterization of Fragile Organometallic Molecules Encapsulated in Single-Wall Carbon Nanotubes Reviewed.
Daisuke Ogawa, Ryo Kitaura, Takeshi Saito, Shinobu Aoyagi, Eiji Nishibori, Makoto Sakata, Tetsuya Nakamura, Hisanori Shinohara. Thermally fragile tris eta 5 -cyclopentadienyl erbium ErCp3 molecules are encapsulated in single-wall carbon nanotubes SWCNTs with high yield. We realized the encapsulation of ErCp3 with high filling ratio by using high quality SWCNTs at an optimized temperature under higher vacuum.
Structure determination based on high-resolution transmission electron microscope observations together with the image simulations reveals the presence of almost free rotation of each ErCp3 molecule in SWCNTs. The encapsulation is also confirmed by X-ray diffraction. Trivalent character of Er ions i. Missing Small-Bandgap Metallofullerenes: Their Isolation and Electronic Properties Reviewed International journal.
Zhiyong Wang, Yusuke Nakanishi, Shoko Noda, Hiroyuki Niwa, Jinying Zhang, Ryo Kitaura, Hisanori Shinohara. Growth of carbon nanotubes via twisted graphene nanoribbons Reviewed. Hong En Lim, Yasumitsu Miyata, Ryo Kitaura, Yoshifumi Nishimura, Yoshio Nishimoto, Stephan Irle, Jamie H. Warner, Hiromichi Kataura, Hisanori Shinohara. Carbon nanotubes have long been described as rolled-up graphene sheets. It is only fairly recently observed that longitudinal cleavage of carbon nanotubes, using chemical, catalytical and electrical approaches, unzips them into thin graphene strips of various widths, the so-called graphene nanoribbons.
In contrast, rolling up these flimsy ribbons into tubes in a real experiment has not been possible. Theoretical studies conducted by Kit et al. recently demonstrated the tube formation through twisting of graphene nanoribbon, an idea very different from the rolling-up postulation. Here we report the first experimental evidence of a thermally induced self-intertwining of graphene nanoribbons for the preferential synthesis of 7, 2 and 8, 1 tubes within parent-tube templates.
Through the tailoring of ribbon's width and edge, the present finding adds a radically new aspect to the understanding of carbon nanotube formation, shedding much light on not only the future chirality tuning, but also contemporary nanomaterials engineering.
Perfectly Ordered Two-Dimensional Layer Structures Found in Some Endohedral Metallofullerenes. Sachiko Maki, Eiji Nishibori, Yutaka Kitamura, Ryo Kitaura, Masayuki Ishihara, Takayuki Aono, Shinobu Aoyagi, Masaki Takata, Makoto Sakata, Hisanori Shinohara.
The determined crystal is a 2D layered structure, which is composed of metallofullerene layers sandwiched by the toluene layers. Although the M C I arrangement in a crystal is almost identical to that of M2Cy C III , the M C I arrangement in a crystal is different from M,Cy C III. It is found that the difference of the molecular arrangement strongly correlates with an orientation of metallofullerenes in a 2D layer.
Rapid Single-Stage Separation of Micrometer-Long and High-Purity Semiconducting Carbon Nanotubes by Gel Filtration. Thendie Boanerges, Miyata Yasumitsu, Kitaura Ryo, MIYAUCHI Yuhei, MATSUDA Kazunari, SHINOHARA Hisanori. Applied physics express Vol. Publishing type： Research paper scientific journal Publisher： Japan Society of Applied Physics. Rapid single-stage separation of micrometer-long and high-purity semiconducting carbon nanotubes by gel filtration Reviewed.
Boanerges Thendie, Yasumitsu Miyata, Ryo Kitaura, Yuhei Miyauchi, Kazunari Matsuda, Hisanori Shinohara. Applied Physics Express Vol. We demonstrate the separation of high-purity, long semiconducting single-wall carbon nanotubes s-SWCNTs by single-stage gel filtration.
Semiconducting SWCNTs are preferentially adsorbed on an allyl dextran-based gel column and then eluted with surfactant solution at a rate that depends on nanotube length as well as electronic type of nanotubes. These differences allow the separation of length-sorted and purity-enhanced s-SWCNTs by fractionated collection of the eluate, which provides the desired nanotubes for electronic device applications.
STM and STS Studies on the Density of States Modulation of Pr C and Sc3C2 C Binary-Metallofullerene Peapods. Yuki Iijima, Kazunori Ohashi, Naoki Imazu, Ryo Kitaura, Ken Kanazawa, Atsushi Taninaka, Osamu Takeuchi, Hidemi Shigekawa, Hisanori Shinohara. The density of states modulation of single-wall carbon nanotubes SWCNTs is induced by the encapsulation of two different kinds of metallofullerenes Pr C and Sc3C2 C The metallofullerene molecules in SWCNTs strongly affect the local band structures of SWCNTs.
The present findings show that the local electronic structures of SWCNTs can be modified by not only varying the geometric structures of SWCNTs but also the varieties of metallofullerenes encapsulated. Fabrication and Characterization of Fully Flattened Carbon Nanotubes: A New Graphene Nanoribbon Analogue Reviewed. Choi, Q. Wang, Y. Azuma, Y. Majima, J. Warner, Y. Miyata, H. Shinohara, R. Graphene nanoribbons GNR are one of the most promising candidates for the fabrication of graphene-based nanoelectronic devices such as high mobility field effect transistors FET.
Here, we report a high-yield fabrication of a high quality another type of GNR analogue, fully flattened carbon nanotubes flattened CNTs , using solution-phase extraction of inner tubes from large-diameter multi-wall CNTs MWCNTs. Transmission electron microscopy TEM observations show that flattened CNTs have width of typically 20 nm and a barbell-like cross section. Measurements of the low-bias conductance of isolated flattened CNTs as a function of gate voltage shows that the flattened CNTs display ambipolar conduction which is different from those of MWCNTs.
The estimated gap based on temperature dependence of conductivity measurements of isolated flattened CNTs is Structure of Tm C I Metallofullerene by Single-Crystal X-ray Diffraction Using the Co-Crystal with Octaethylporphyrin Nickel Ni OEP. Yuki Sado, Shinobu Aoyagi, Ryo Kitaura, Yasumitsu Miyata, Eiji Nishibori, Hiroshi Sawa, Kunihisa Sugimoto, Hisanori Shinohara.
The molecular structure of Tm C isomer I is revealed by single-crystal X-ray diffraction of the cocrystal with nickel octaethylporphyrin Ni OEP. A rotational movement of Tm C I molecule in the cocrystal is dramatically suppressed by the coordination of two Ni OEP ligands in the cocrystal.
The structure of Tm C I in the crystal is explained by the orientation disorder with two different orientations. The so-obtained carbon cage structure is C-5 6 -C The restricted molecular orientations of Tm C I in the cocrystal are achieved by the molecular dipole moment of Tm C 1 that interacts with two Ni OEP ligands.
The present study suggests that the intermolecular interactions can reduce the degree of freedom in the orientation of spherical metallofullerene molecules in the crystals and complexes. Thin single-wall BN-nanotubes formed inside carbon nanotubes Reviewed. Ryo Nakanishi, Ryo Kitaura, Jamie H. Warner, Yuta Yamamoto, Shigeo Arai, Yasumitsu Miyata, Hisanori Shinohara. We report a high yield synthesis of single-wall boron nitride nanotubes SWBNNTs inside single-wall carbon nanotubes SWCNTs , a nano-templated reaction, using ammonia borane complexes ABC as a precursor.
Transmission electron microscope TEM , high angle annular dark field HAADF -scanning TEM STEM , electron energy loss spectra EELS and high resolution EELS mapping using aberration-corrected TEM system clearly show the formation of thin SWBNNTs inside SWCNTs. We have found that the yield of the SWBNNT formation is high and that the most of ABC molecules decompose and fuse to form the thin BNNTs at a temperature of 1, K having a narrow diameter distribution of 0.
Optical absorption measurements suggest that the band gap of the thin SWBNNTs is about 6. Significance of horizontal propagation of synchronized activities in human epileptic neocortex investigated by optical imaging and immunohistological study.
Hiraishi T, Kitaura H, Oishi M, Fukuda M, Kameyama S, Takahashi H, Kakita A, Fujii Y. Epilepsy research Vol. Evidence of Diamond Nanowires Formed inside Carbon Nanotubes from Diamantane Dicarboxylic Acid Reviewed. Jinying Zhang, Zhen Zhu, Yanquan Feng, Hitoshi Ishiwata, Yasumitsu Miyata, Ryo Kitaura, Jeremy E.
Dahl, Robert M. Carlson, Natalie A. Fokina, Peter R. Schreiner, David Tomanek, Hisanori Shinohara. Ahmadreza Fallah, Yuki Yonetani, Ryosuke Senga, Kaori Hirahara, Ryo Kitaura, Hisanori Shinohara, Yoshikazu Nakayama.
Nanoscale Vol. Sc3N C80 fullerenes are inserted inside carbon nanotubes CNTs. This value is an order of magnitude higher than the threshold of electron-induced damage in C60 molecules. Electron energy loss spectroscopy confirms the presence of Sc atoms in capsules.
Chirally selective growth and extraction of single-wall carbon nanotubes via fullerene nano-peapods Reviewed. Jinying Zhang, Feng Zhou, Yasumitsu Miyata, Ryo Kitaura, Haibin Su, Hisanori Shinohara. RSC ADVANCES Vol. Single-wall carbon nanotubes SWCNTs grown from C and C inside SWCNTs with diameters of 1.
The as-produced SWCNTs have been extracted, separated, and characterized. The products from C are dominated by 7,6 and 9,4 SWCNTs, whereas those from C are dominated by 6,5 SWCNTs. Yun Sun, Ryo Kitaura, Takuya Nakayama, Yasumitsu Miyata, Hisanori Shinohara. NANO Vol. The influences of synthesis parameters on the mean diameter and diameter distribution of as-grown single-wall carbon nanotubes SWCNTs with chemical vapor deposition CVD using the mist flow method have been investigated in detail with Raman spectroscopy, scanning electron microscopy SEM and transmission electron microscopy TEM.
We found that CVD reaction temperature and flow rate play an essential role in controlling the mean diameter and the quality of as-grown SWCNTs. Furthermore, we found that the carbon supply kinetics can be a dominant factor to determine the diameter of as-grown SWCNTs in the present mist flow method. Under a different combination of various parameters, the mean diameter of SWCNTs can be varied from 0. Synthesis and Transformation of Linear Adamantane Assemblies inside Carbon Nanotubes Reviewed.
Jinying Zhang, Yanquan Feng, Hitoshi Ishiwata, Yasumitsu Miyata, Ryo Kitaura, Jeremy E. Carlson, Hisanori Shinohara, David Tomanek. We report the assembly and thermal transformation of linear diamondoid assemblies inside carbon nanotubes.
Our calculations and observations indicate that these molecules undergo selective reactions within the narrow confining space of a carbon nanotube. Upon vacuum annealing of adamantane molecules encapsulated in a carbon nanotube, we observe a sharp Raman feature at cm -1 , which we interpret as a stretching mode of carbon chains formed by thermal conversion of adamantane inside a carbon nanotube.
Introduction of pure hydrogen during thermal annealing, however, suppresses the formation of carbon chains and seems to keep adamantane intact. Topological Difference in 2D Layers Steers the Formation of Rigid and Flexible 3D Supramolecular Isomers: Impact on the Adsorption Properties Reviewed.
Prakash Kanoo, Ryotaro Matsuda, Ryo Kitaura, Susumu Kitagawa, Tapas Kumar Maji. INORGANIC CHEMISTRY Vol. Language： English Publishing type： Research paper scientific journal Publisher： AMER CHEMICAL SOC. Starting with the same precursors, pyridine-2,3-dicarboxylate pyrdc and 4,4'-bipyridyl bipy , two 3D porous coordination polymers, [Cu bipy 0.
Single-crystal structure analysis revealed that 1 and 2 are supramolecular isomers with 3D pillared-layer structures having 1D channel systems. Isomer 1 has a flexible structure and shows gated adsorption behavior, while framework 2 has a rigid backbone and exhibits the adsorption properties of typical microporous materials.
Yasumitsu Miyata, Eriko Maeda, Keiichi Kamon, Ryo Kitaura, Yuki Sasaki, Shoji Suzuki, Hisanori Shinohara. Publishing type： Research paper scientific journal Publisher： JAPAN SOC APPLIED PHYSICS. The synthesis of graphene and hexagonal boron nitride hBN hybrid sheets has been achieved using a two-step chemical vapor deposition CVD process.
Individual grains of single-layer graphene are grown from methane, and hBN is, then, synthesized from ammonia borane on the same copper Cu foil. Optical absorption and Raman measurements reveal that the hBN is formed on the bare surface of Cu foil and the graphene grains play a crucial role as an inactive protective layer of Cu foil for the ammonia borane CVD.
Furthermore, the hBN growth is found to be initiated preferentially by the edge of graphene grains. Dimerization-Initiated Preferential Formation of Coronene-Based Graphene Nanoribbons in Carbon Nanotubes.
Miho Fujihara, Yasumitsu Miyata, Ryo Kitaura, Yoshifumi Nishimura, Cristopher Camacho, Stephan Irle, Yoko Iizumi, Toshiya Okazaki, Hisanori Shinohara. We have investigated the growth mechanism of coronene-derived graphene nanoribbons GNRs using two different precursors: coronene and a dimer form of coronene, so-called dicoronylene C48H For both of the precursors, the formation of nanoribbon-like materials inside carbon nanotubes CNTs was confirmed by transmission electron microscope observations.
Experimental and theoretical Raman analysis reveals that the samples also encapsulated dicoronylene and linearly condensed other coronene oligomers, which can be regarded as analogues to GNRs. Interestingly, it was found that the present doping condition of coronene yields dicoronylene prior to encapsulation due to the thermal dimerization of coronene. These results indicate that the dimerization before the encapsulation drives the preferential formation of the coronene-based GNRs within CNTs.
Preparation and Observation of an Atomic Layer of Gold Formed on the Surface of Graphene. Sasaki Yuki, Kitaura Ryo, Yamamoto Yuta, ARAI Shigeo, SUZUKI Shoji, MIYATA Yasumitsu, SHINOHARA Hisanori. Preparation and Observation of an Atomic Layer of Gold Formed on the Surface of Graphene Reviewed.
Yuki Sasaki, Ryo Kitaura, Yuta Yamamoto, Shigeo Arai, Shoji Suzuki, Yasumitsu Miyata, Hisanori Shinohara. Freestanding clean graphene is prepared using graphene samples grown by chemical vapor deposition and direct transfer onto a SiN grid followed by hydrogen plasma treatment.
High-resolution transmission electron microscopy has shown that the Au atoms deposited on the graphene possess a unique layer structure with a square arrangement of Au atoms. We found that the Au nanostructure vaporizes under mild electron beam irradiation conditions, which is specific to the unique thin layer structure. Rock-Salt-Type Crystal of Thermally Contracted C60 with Encapsulated Lithium Cation Reviewed. Shinobu Aoyagi, Yuki Sado, Eiji Nishibori, Hiroshi Sawa, Hiroshi Okada, Hiromi Tobita, Yasuhiko Kasama, Ryo Kitaura, Hisanori Shinohara.
Dimerization-Initiated Preferential Formation of Coronene-Based Graphene Nanoribbons in Carbon Nanotubes Reviewed. Fujihara, Miho; Miyata, Yasumitsu; Kitaura, Ryo; et al. Journal of Physical Chemistry C Vol. Nakanishi, Ryo; Kitaura, Ryo; Ayala, Paola; et al. Physical Review B Vol. Growth of large-diameter similar to 4 nm single-wall carbon nanotubes in the nanospace of mesoporous material SBA Reviewed.
Keita Kobayashi, Ryo Kitaura, Fumihiro Nishimura, Hirofumi Yoshikawa, Kunio Awaga, Hisanori Shinohara. Publishing type： Research paper scientific journal Publisher： PERGAMON-ELSEVIER SCIENCE LTD.
Single-wall carbon nanotubes SWCNTs have been synthesized by supported-catalyst chemical vapor deposition CCVD using one-dimensional 1D channels of mesoporous silica SBA; mean channel diameter, 6. The synthesized SWCNTs have much larger diameters than the SWCNTs synthesized by conventional CCVD.
Large metal particles formed in the channels should play an important role in the growth of the SWCNTs with larger diameters. Length-Sorted Semiconducting Carbon Nanotubes for High-Mobility Thin Film Transistors Reviewed.
Yasumitsu Miyata, Kazunari Shiozawa, Yuki Asada, Yutaka Ohno, Ryo Kitaura, Takashi Mizutani, Hisanori Shinohara. Publishing type： Research paper scientific journal Publisher： TSINGHUA UNIV PRESS.
We have developed a process for chemical purification of carbon nanotubes for solution-processable thin-film transistors TFTs having high mobility. Films of the purified carbon nanotubes fabricated by simple drop coating showed carrier mobilities as high as cm 2 V -1 s -1 , normalized transconductances of 0.
Such high performance requires the preparation of a suspension of micrometer-long and highly purified semiconducting single-walled carbon nanotubes SWCNTs. Our purification process includes length and electronic-type selective trapping of SWCNTs using recycling gel filtration with a mixture of surfactants.
The results provide an important milestone toward printed high-speed and large-area electronics with roll-to-roll and ink-jet device fabrication. Purity-enhanced bulk synthesis of thin single-wall carbon nanotubes using iron-copper catalysts Reviewed. Lim, Y. Miyata, T. Nakayama, S. Chen, R. Kitaura, H. We report high purity and high yield synthesis of single-wall carbon nanotubes SWCNTs of narrow diameter from iron-copper bimetal catalysts.
The SWCNTs with diameter of 0. Single metal and bimetal catalysts are systematically investigated to achieve both the enhancement of SWCNT yield and the suppression of the undesired formation of graphitic impurities.
The relative yield and purity of SWCNTs are quantified using optical absorption spectroscopy with an ultracentrifuge-based purification technique. For the single metal catalyst, iron shows the highest catalytic activity compared with the other metals such as cobalt, nickel, molybdenum, copper, and platinum. It has been found that the addition of copper to iron results in the suppression of carbonaceous impurity formation without decreasing the SWCNT yield.
The purity-enhanced SWCNT shows fairly low sheet resistance due to the improvement of inter-nanotube contacts. This scalable design of SWCNT synthesis with enhanced purity is therefore a promising tool for shaping future high performance devices. Growth of Linear Carbon Chains inside Thin Double-Wall Carbon Nanotubes Reviewed. Zhao, R. Hara, S. Irle, H. Fusion reactions of size-selected linear polyyne molecules, C 10 H 2 , in the ultrathin one-dimensional 1D nanospace of double wall carbon nanotubes DWCNTs have been observed, leading to the formation of very long linear carbon chains.
The formation and growth of long linear carbon chains is investigated by Raman spectroscopy and density-functional tight-binding-based molecular dynamics simulations. The high-resolution transmission electron microscope images of C 10 H 2 DWCNTs show that the encapsulated linear C 10 H 2 molecules have a length of 1. After the high temperature annealing at K under high vacuum conditions, new Raman bands appear at cm -1 , and the Raman bands arising from encapsulated pristine polyyne molecules at cm -1 completely disappear.
This is clear evidence that a fusion reaction occurs to form long linear carbon chains inside the ID nanospace of DWCNTs. Direct HRTEM Observation of Ultrathin Freestanding Ionic Liquid Film on Carbon Nanotube Grid Reviewed. Shimou Chen, Keita Kobayashi, Ryo Kitaura, Yasumitsu Miyata, Hisanori Shinohara.
Direct imaging of liquids by electron microscopy has been extremely difficult due to their high volatility. Ionic liquids are a unique liquid material with almost zero vapor pressure, which allows us to characterize them under high-vacuum conditions. Here we report the first direct observation of the microstructure and phase behavior of an imidazolium-based room-temperature ionic liquid by high-resolution transmission electron microscopy with the aid of a special carbon nanotube network, which is able to support a freestanding ultrathin ionic liquid film on its nanosized holes.
It was found that the existence of cluster structures is one of the intrinsic properties of the ionic liquid in its whole liquid phase range. Furthermore, the size and mobility of the clusters play an important role during phase transition of the ionic liquid. We show that the direct HRTEM imaging on freestanding liquid film is a powerful technique to obtain insight into the structure of ionic liquids and their phase behavior.
The present study can provide an important starting point for more sophisticated structural studies on the microstructure of liquidus materials. Low voltage electron diffractive imaging of atomic structure in single-wall carbon nanotubes Reviewed.
Osamu Kamimura, Yosuke Maehara, Takashi Dobashi, Keita Kobayashi, Ryo Kitaura, Hisanori Shinohara, Hiroyuki Shioya, Kazutoshi Gohara. Publishing type： Research paper scientific journal Publisher： AMER INST PHYSICS. The demand for atomic-scale analysis without serious damage to the specimen has been increasing due to the spread of applications with light-element three-dimensional 3D materials.
Low voltage electron diffractive imaging has the potential possibility to clarify the atomic-scale structure of 3D materials without causing serious damage to specimens. We demonstrate low-voltage 30 kV electron diffractive imaging of single-wall carbon nanotube at a resolution of 0.
In the reconstructed pattern, the intensity difference between single carbon atom and two overlapping atoms can be clearly distinguished. The present method can generally be applied to other materials including biologically important ones. C American Institute of Physics.
Irregular Modulation of Density-of-States of Nano-Peapods Encapsulating Gd C Metallofullerenes Reviewed. Kazunori Ohashi, Naoki Imazu, Ryo Kitaura, Hisanori Shinohara. We demonstrate that internal orientation of Gd C molecules inside SWCNTs can strongly affect the electronic structure of SWCNTs.
The present findings suggest that not only encapsulated molecules but also their molecular orientations can be a tunable parameter with which we can modulate local electronic structures of SWCNTs. A resonant photoemission insight to the electronic structure of Gd nanowires templated in the hollow core of SWCNTs Reviewed. Ayala, R. Kitaura, C. Kramberger, H. Shiozawa, N. Imazu, K. Kobayashi, D. Mowbray, P. Hoffmann, H. Shinohara, T. Express Vol. Templating rare-earth hybridization via ultrahigh vacuum annealing of ErCl3 nanowires inside carbon nanotubes Reviewed.
Paola Ayala, Ryo Kitaura, Ryo Nakanishi, Hidetsugu Shiozawa, Daisuke Ogawa, Patrick Hoffmann, Hinsanori Shinohara, Thomas Pichler. Here we report on controlling the effective hybridization and charge transfer of rare-earth elements inside a carbon nanotube CNT nanoreactor.
The tubular space inside CNTs can encapsulate one-dimensional 1D crystals such as ErCl3, which we have used as a starting material. Applying a thermochemical reaction in ultrahigh vacuum, we obtain elemental Er nanowires still encapsulated in the CNTs. The hybridization degree and the effective charge changes were directly accessed across the Er 4d and 3d edges by high-energy spectroscopy. It was found that Er is trivalent but the effective valence is reduced for the Er-filled tube, which strongly suggests an increased hybridization between the nanotube pi states and the Er 5d orbitals.
This was also evidenced by the conduction band response determined in C1s-x-ray absorption spectroscopy XAS. These results have significant implications for the 1D electronic and magnetic properties of these and similar rare-earth nanowire hybrids.
Thin-Film Transistors with Length-Sorted DNA-Wrapped Single-Wall Carbon Nanotubes Reviewed. Yuki Asada, Yasumitsu Miyata, Kazunari Shiozawa, Yutaka Ohno, Ryo Kitaura, Takashi Mizutani, Hisanori Shinohara.
The present experimental study provides a detailed characterization of the single-wall carbon nanotube SWNT length effect on the device characteristics of DNA-wrapped SWNT-network thin-film transistors TFTs. DNA-assisted dispersion and length separation by high-performance liquid chromatography are used to prepare the SWNTs with average lengths of and rim. The optimized density of nm SWNTs is found to be higher than that of nm SWNTs as expected by the percolation theory of two-dimensional random networks, where shorter length SWNTs can maintain high on current despite increasing in the number of SWNT junctions.
The present result is an important indicator for realizing high-performance TFTs constructed from SWNTs having desired length. Lei B, Hitomi H, Mori T, Nagai Y, Deguchi K, Mori H, Masaki T, Nakano D, Kobori H, Kitaura Y, Nishiyama A. Journal of pharmacological sciences Vol. Transformation of ionic liquid into carbon nanotubes in confined nanospace Reviewed. Shimou Chen, Hong En Lim, Yasumitsu Miyata, Ryo Kitaura, Yoshio Bando, Dmitri Golberg, Hisanori Shinohara. We have developed a two-step filling process for the nano-reaction of ionic liquid in a tip-closed SWNT, where fullerenes are inserted at the end of the host SWNT as a plug to prevent the leakage of the confined ionic liquid during heat treatment.
Preferential synthesis and isolation of 6,5 single-wall nanotubes from one-dimensional C coalescence Reviewed. Jinying Zhang, Yasumitsu Miyata, Ryo Kitaura, Hisanori Shinohara. The 6,5 single-wall carbon nanotubes have been preferentially synthesized from a one-dimensional array of C inside single-wall carbon nanotubes d congruent to 1.
The as-produced inner tubes have been extracted via sonication and density gradient ultracentrifugation methods and demonstrated to be dominated by 6,5 tubes by optical absorption, Raman scattering, photoluminescence, high-resolution transmission electron microscope observation, and a semi-empirical simulation PM3. Nanohybridization of Polyoxometalate Clusters and Single-Wall Carbon Nanotubes: Applications in Molecular Cluster Batteries Reviewed. Naoya Kawasaki, Heng Wang, Ryo Nakanishi, Shun Hamanaka, Ryo Kitaura, Hisanori Shinohara, Toshihiko Yokoyama, Hirofumi Yoshikawa, Kunio Awaga.
Scanning tunnelling spectroscopy on the local electronic structure of Gd C peapods Reviewed. PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS Vol.
Publishing type： Research paper scientific journal Publisher： WILEY-BLACKWELL. The electronic structure of Gd C metallofullerene peapods is studied experimentally by using scanning tunnelling microscopy and spectroscopy STM and STS. The spatial modulation of the nanotube electronic structure induced by Gd C encapsulation has been observed depending on the position along the tube axis.
Both STM and STS reveal a 1. KGaA, Weinheim. Solution-Phase Extraction of Ultrathin Inner Shells from Double-Wall Carbon Nanotubes Reviewed. Yasumitsu Miyata, Marie Suzuki, Miho Fujihara, Yuki Asada, Ryo Kitaura, Hisanori Shinohara. We present an efficient method to extract inner shells of double-wall carbon nanotubes DWCNTs in liquid phase. The extraction of inner from outer shells is achieved by cutting the DWCNTs with vigorous sonication in water containing surfactants.
The extracted shells are perfectly isolated single-wall carbon nanotubes SWCNTs and can be separated using density gradient ultracentrifugation. Statistical analysis using high-resolution transmission electron microscopy reveals that the enrichment of SWCNTs with narrow diameter 0.
Furthermore, the 5,4 SWCNTs, which have the diameter of 0. Our findings provide a novel way to obtain very narrow, highly isolated SWCNTs with ultraclean surface that have not been obtained in conventional synthesis methods. A layered ionic crystal of polar Li C superatoms Reviewed. Shinobu Aoyagi, Eiji Nishibori, Hiroshi Sawa, Kunihisa Sugimoto, Masaki Takata, Yasumitsu Miyata, Ryo Kitaura, Hisanori Shinohara, Hiroshi Okada, Takeshi Sakai, Yoshihiro Ono, Kazuhiko Kawachi, Kuniyoshi Yokoo, Shoichi Ono, Kenji Omote, Yasuhiko Kasama, Shinsuke Ishikawa, Takashi Komuro, Hiromi Tobita.
NATURE CHEMISTRY Vol. If the physical properties of C fullerene molecules can be controlled in C products already in use in various applications, the potential for industrial development will be significant. Encapsulation of a metal atom in the C fullerene molecule is a promising way to control its physical properties. However, the isolation of Cbased metallofullerenes has been difficult due to their insolubility. Here, we report the complete isolation and determination of the molecular and crystal structure of polar cationic Li C metallofullerene.
The physical and chemical properties of Li C cation are compared with those of pristine C The present method of purification and crystallization of Cbased metallofullerenes provides a new C fullerene material that contains a metal atom.
A simple alcohol-chemical vapor deposition synthesis of single-layer graphenes using flash cooling Reviewed. Yasumitsu Miyata, Keiichi Kamon, Kazunori Ohashi, Ryo Kitaura, Masamichi Yoshimura, Hisanori Shinohara.
We report the synthesis of single-layer graphenes from ethanol using, what we call, "flash cooling" just after chemical vapor deposition. The single-layer graphenes synthesized are high-quality and several micrometers in grain size as revealed by Raman spectroscopy. Detailed comparison of the cooling processes suggests that the single-layer graphene growth does not occur during the carbon precipitation but rather stems from surface diffusions of carbon on a nickel substrate.
Because of the present simple and easiness for the large-scale synthesis under an inert gas atmosphere and at atmospheric pressure, the present method can easily be applied for the future large-scale and low-cost graphene production.
High-Performance Thin-Film Transistors with DNA-Assisted Solution Processing of Isolated Single-Walled Carbon Nanotubes Reviewed. Yuki Asada, Yasumitsu Miyata, Yutaka Ohno, Ryo Kitaura, Toshiki Sugai, Takashi Mizutani, Hisanori Shinohara. ADVANCED MATERIALS Vol. Effect of a pick-and-drop process on optical properties of a CVD-grown monolayer tungsten disulfide Reviewed. Yusuke Hoshi, Mitsuhiro Okada, Rai Moriya, Satoru Masubuchi, Kenji Watanabe, Takashi Taniguchi, Ryo Kitaura, Tomoki Machida.
Physical Review Materials Vol. We systematically investigated changes of a photoluminescence PL spectral shape by picking a tungsten disulfide monolayer 1L-WS2 grown on a sapphire SA substrate and dropping it on various substrates such as SA, SiO2, and hexagonal boron nitride hBN.
An inhomogeneous contribution to the exciton PL linewidth was reduced by picking the CVD-grown 1L-WS2, meaning potential energy disorder lowering in the 1L-WS2. In addition, a defect-bound exciton peak was not seen at low temperature for all the samples with the pick-and-drop process although it was clearly observed for the as-grown sample.
It was thought that the as-grown 1L-WS2 was covalently bonded on the SA substrate surface due to the existence of crystal imperfections in the WS2 and the covalent bonds formed midgap states.
A PL spectrum had to be carefully treated in order to fairly evaluate a crystal quality in a CVD-grown 1L-WS2 since PL spectral shapes were determined by complexes of the defect density with other mechanisms such as strain fluctuation and a connection with the substrate. Kenshi Miyaura, Yasumitsu Miyata, Boanerges Thendie, Kazuhiro Yanagi, Ryo Kitaura, Yuta Yamamoto, Shigeo Arai, Hiromichi Kataura, Hisanori Shinohara.
Scientific Reports Vol. Language： English Publishing type： Research paper scientific journal Publisher： Nature Publishing Group. In this process, thiophene-based oligomers are encapsulated within CNTs as precursors and are subsequently polymerized by thermal annealing.
This polymerization increases the effective conjugation length of the thiophenes, as confirmed by transmission electron microscopy and absorption peak red shifts. This work also demonstrates that these polythiophenes can serve as effective markers for individual CNTs during Raman imaging with single-wavelength laser excitation due to their strong absorbance. In addition, stable carrier injection into the encapsulated polythiophenes is found to be possible via electrochemical doping.
Development of a new knock-in mouse model and evaluation of pharmacological activities of lusutrombopag, a novel, nonpeptidyl small-molecule agonist of the human thrombopoietin receptor c-Mpl.
Yoshida H, Yamada H, Nogami W, Dohi K, Kurino-Yamada T, Sugiyama K, Takahashi K, Gahara Y, Kitaura M, Hasegawa M, Oshima I, Kuwabara K. Experimental hematology Vol. e2 Exciton Diffusion in a hBN-encapsulated Monolayer Transition Metal Dichalcogenide. Publishing type： Research paper scientific journal Publisher： Optics InfoBase Conference Papers. Takato Hotta, Shohei Higuchi, Yosuke Uchiyama, Keiji Ueno, Kenji Watanabe, Takashi Taniguchi, Hisanori Shinohara, Ryo Kitaura.
All rights reserved. Excitons are bound states of an electron and a hole through Coulomb interaction. Optical responses from low-dimensional systems, such as transition metal dichal-cogenides TMDs , is dominated by the excitonic effect even at room temperature, and exciton diffusion is one of the most important processes for understanding optical response of TMDs.
To address intrinsic exciton diffusion in TMDs, extrinsic effects, such as substrate effects, need to be suppressed. In this work, we have conducted systematic investigations of exciton diffusion in a hBN-encapsulated monolayer MoSe2. Femtosecond Laser Filamentation in Gaseous Ethylene: Formation of Hydrogenated Amorphous Carbon. Matsuda Akitaka, Hayashi Takahiro, Kitaura Ryo, Hishikawa Akiyoshi. Chemistry Letters Vol. Language： Japanese Publishing type： Research paper scientific journal Publisher： The Chemical Society of Japan.
It is shown that hydrogenated amorphous carbon a-C:H films and nanoparticles are produced by the strong interactions with the intense laser fields ca.
Modulation of the Local Density of States of Carbon Nanotubes by Encapsulation of Europium Nanowires As Observed by Scanning Tunneling Microscopy and Spectroscopy. Terunobu Nakanishi, Ryo Kitaura, Takazumi Kawai, Susumu Okada, Shoji Yoshida, Osamu Takeuchi, Hidemi Shigekawa, Hisanori Shinohara.
JOURNAL OF PHYSICAL CHEMISTRY C Vol. Modulation of the local density of states of single-wall carbon nanotubes SWCNTs is induced by the encapsulation of europium nanowires EuNWs. The electronic modulation of SWCNTs by encapsulation of EuNWs is revealed as a Fermi level: shift, band gap reduction and the emergence, of localized states in the gap. The present results show that the electronic interaction between EuNWs and SWCNTs is much stronger than that previously reported for nanomaterials encapsulated in SWCNTs.
Fexofenadine Suppresses Delayed-Type Hypersensitivity in the Murine Model of Palladium Allergy. Matsubara R, Kumagai K, Shigematsu H, Kitaura K, Nakasone Y, Suzuki S, Hamada Y, Suzuki R. International journal of molecular sciences Vol. Suppression of exciton-exciton annihilation in tungsten disulfide monolayers encapsulated by hexagonal boron nitrides Reviewed. Yusuke Hoshi, Takashi Kuroda, Mitsuhiro Okada, Rai Moriya, Satoru Masubuchi, Kenji Watanabe, Takashi Taniguchi, Ryo Kitaura, Tomoki Machida.
Language： English Publishing type： Research paper scientific journal Publisher： AMER PHYSICAL SOC. We investigates exciton-exciton annihilation EEA in tungsten disulfide WS2 monolayers encapsulated by hexagonal boron nitride hBN. Thus, the observed EEA rate reduction played a key role in enhancing luminescence intensity at high exciton densities in the WS2 monolayer. Orientation-controlled growth of hexagonal boron nitride monolayers templated from graphene edges Reviewed. Eriko Maeda, Yasumitsu Miyata, Hiroki Hibino, Yu Kobayashi, Ryo Kitaura, Hisanori Shinohara.
The crystal orientation of epitaxially grown hexagonal boron nitride hBN monolayers from graphene edges was investigated. Low-energy electron microscopy observations reveal that the orientation of individual hBN grains is dependent on the direction of the templated zigzag edges of graphene. Furthermore, the triangular atomic defects in hBN were used to confirm the orientation of epitaxial hBN through high-resolution transmission electron microscopy observations.
C The Japan Society of Applied Physics. Observation of biexcitonic emission at extremely low power density in tungsten disulfide atomic layers grown on hexagonal boron nitride Reviewed International journal. Mitsuhiro Okada, Yuhei Miyauchi, Kazunari Matsuda, Takashi Taniguchi, Kenji Watanabe, Hisanori Shinohara, Ryo Kitaura.
Monolayer transition metal dichalcogenides TMDCs including WS2, MoS2, WSe2 and WS2, are two-dimensional semiconductors with direct bandgap, providing an excellent field for exploration of many-body effects in 2-dimensions 2D through optical measurements.
To fully explore the physics of TMDCs, the prerequisite is preparation of high-quality samples to observe their intrinsic properties. For this purpose, we have focused on high-quality samples, WS2 grown by chemical vapor deposition method with hexagonal boron nitride as substrates. The results clearly demonstrate that the present samples can provide an excellent field, where one can observe various excitonic states, offering possibility of exploring optical physics in 2D and finding new condensates.
Molecular beam epitaxy growth of monolayer niobium diselenide flakes Reviewed. Takato Hotta, Takuto Tokuda, Sihan Zhao, Kenji Watanabe, Takashi Taniguchi, Hisanori Shinohara, Ryo Kitaura. APPLIED PHYSICS LETTERS Vol. Monolayer niobium diselenide NbSe2 is prepared through molecular beam epitaxy with hexagonal boron nitride hBN as substrates.
Atomic force microscopy and the Raman spectroscopy have shown that the monolayer NbSe2 grown on the hBN possesses triangular or truncated triangular shape whose lateral size amounts up to several hundreds of nanometers. We have found that the precisely controlled supply rate and ultraflat surface of hBN plays an important role in the growth of the monolayer NbSe2.
Published by AIP Publishing. Overexpression of ErbB4 is an independent marker for lymph node metastasis in Japanese patients with oral squamous cell carcinoma. Ohashi Y, Kumagai K, Miyata Y, Matsubara R, Kitaura K, Suzuki S, Hamada Y, Suzuki R. Oral surgery, oral medicine, oral pathology and oral radiology Vol. Simple fabrication of air-stable black phosphorus heterostructures with large-area hBN sheets grown by chemical vapor deposition method Reviewed.
Sapna Sinha, Yuya Takabayashi, Hisanori Shinohara, Ryo Kitaura. We have developed a facile and general method to passivate thin black phosphorus BP flakes with large-area high-quality monolayer hexagonal boron nitride hBN sheets grown by the chemical vapor deposition CVD method. In spite of the one-atom-thick structure, the high-quality CVD-grown monolayer hBN has proven to be useful to prevent the degradation of thin BP flakes exfoliated on substrates.
Mechanically exfoliated BP flakes prepared on a Si substrate are covered by the monolayer hBN sheet to preserve otherwise unstable atomic layered BP flakes from degradation. The present technique can generally be applied to fabricating BP-based electronic devices with much easiness. Construction of Covalent Organic Nanotubes by Light-Induced Cross-Linking of Diacetylene-Based Helical Polymers. Kaho Maeda, Liu Hong, Taishi Nishihara, Yusuke Nakanishi, Yuhei Miyauchi, Ryo Kitaura, Naoki Ousaka, Eiji Yashima, Hideto Ito, Kenichiro Itami.
Journal of the American Chemical Society Vol. While most ONTs are constructed by self-assembly processes based on weak noncovalent interactions, this unique property gives rise to the inherent instability of their tubular structures.
Herein, we report a simple "helix-to-tube" strategy to construct robust, covalent ONTs from easily accessible poly m-phenylene diethynylene s poly-PDEs possessing chiral amide side chains that can adopt a helical conformation through hydrogen-bonding interactions.
The helically folded poly-PDEs subsequently undergo light-induced cross-linking at longitudinally aligned 1,3-butadiyne moieties across the whole helix to form covalent tubes ONTs both in solution and solid phases. The structures of poly-PDEs and covalent ONTs were characterized by spectroscopic analyses, diffraction analysis, and microscopic analyses.
We envisage that this simple yet powerful "helix-to-tube" strategy will generate a range of ONT-based materials by introducing functional moieties into a monomer. Origin of residual particles on transferred graphene grown by CVD Reviewed. Tomohiro Yasunishi, Yuya Takabayashi, Shigeru Kishimoto, Ryo Kitaura, Hisanori Shinohara, Yutaka Ohno.
Large-area single-layer graphene can be grown on Cu foil by CVD, but for device applications, the layer must to be transferred onto an insulating substrate.
As residual particles are often observed on transferred graphene, we investigated their origin using scanning electron microscopy and energy-dispersive X-ray spectrometry EDX. The results show that these residual particles are composed either of silicon or an alloy of a few metals, and hence, likely originate from the quartz tube of the CVD furnace and the impurities contained in the Cu foil.
Two-dimensional metallic NbS2: growth, optical identification and transport properties Reviewed. Sihan Zhao, Takato Hotta, Takashi Koretsune, Kenji Watanabe, Takashi Taniguchi, Katsuaki Sugawara, Takashi Takahashi, Hisanori Shinohara, Ryo Kitaura.
Progress on researches of two-dimensional 2D metals strongly relies on development of the growth technique. Studies on preparation of 2D metals have so far been limited, and this is in stark contrast to the situation of 2D semiconductors, where various layered semiconductors, including MoS2, WS2, MoSe2, WSe2, have been isolated in its monolayer form. In this work, we have developed a facile method to prepare 2D metallic transition metal dichalcogenides TMDCs by chemical vapor deposition CVD method, where direct growth of few-layered NbS2 3R phase on atomically flat hexagonal boron nitride hBN has been demonstrated.
Structural characterization of the so-grown NbS2 was performed with atomic force microscopy, optical microscopy, electron microscopy and optical spectroscopy, revealing that the utilization of hBN as growth substrates is a key factor for the first successful CVD growth of 2D metallic TMDCs with large single-domain size several mu m.
Electrical transport measurements have clearly shown that NbS2 atomic layers down to few-layer-thickness are metal. The current study opens up a new synthetic route for controllable growth of 2D layered metallic materials, which is of great importance in study of rich physics in 2D metals, as well as in search for novel 2D superconductors.
Efficient preparation of graphene liquid cell utilizing direct transfer with large-area well-stitched graphene Reviewed. Yuki Sasaki, Ryo Kitaura, Jong Min Yuk, Alex Zettl, Hisanori Shinohara. CHEMICAL PHYSICS LETTERS Vol. Language： Japanese Publishing type： Research paper scientific journal Publisher： ELSEVIER SCIENCE BV. By utilizing graphene-sandwiched structures recently developed in this laboratory, we are able to visualize small droplets of liquids in nanometer scale.
We have found that small water droplets as small as several tens of nanometers sandwiched by two single-layer graphene are frequently observed by TEM. Due to the electron beam irradiation during the TEM observation, these sandwiched droplets are frequently moving from one place to another and are subjected to create small bubbles inside.
The synthesis of a large area single-domain graphene of high-quality is essential to prepare the graphene sandwiched cell which safely encapsulates the droplets in nanometer size.
C Elsevier B. Importance of Three-Body Interactions in Molecular Dynamics Simulations of Water Demonstrated with the Fragment Molecular Orbital Method. Pruitt SR, Nakata H, Nagata T, Mayes M, Alexeev Y, Fletcher G, Fedorov DG, Kitaura K, Gordon MS.
Journal of chemical theory and computation Vol. Possible Immune Regulation of Natural Killer T Cells in a Murine Model of Metal Ion-Induced Allergic Contact Dermatitis. Kumagai K, Horikawa T, Shigematsu H, Matsubara R, Kitaura K, Eguchi T, Kobayashi H, Nakasone Y, Sato K, Yamada H, Suzuki S, Hamada Y, Suzuki R. Isolation and Structure Determination of a Missing Endohedral Fullerene La C through In Situ Trifluoromethylation Reviewed International journal.
Zhiyong Wang, Shinobu Aoyagi, Haruka Omachi, Ryo Kitaura, Hisanori Shinohara. D-5h-symmetric fullerene C D-5h-C is one of the most abundant members of the fullerene family. One longstanding mystery in the field of fullerene chemistry is whether D-5h-C is capable of accommodating a rare-earth metal atom to form an endohedral metallofullerene M D-5h-C, which would be expected to show novel electronic properties.
The molecular structure of La C remains unresolved since its discovery three decades ago because of its extremely high instability under ambient conditions and insolubility in organic solvents. Herein, we report the single-crystal X-ray structure of La C CF3 3 , which was obtained through in situ exohedral functionalization by means of trifluoromethylation.
The X-ray crystallographic study reveals that La C CF3 3 is the first example of an endohedral rare-earth fullerene based on D5hC The dramatically enhanced stability of La C CF3 3 compared to La C can be ascribed to trifluoromethylationinduced bandgap enlargement.
Single atom spectroscopy: Decreased scattering delocalization at high energy losses, effects of atomic movement and X-ray fluorescence yield Reviewed International journal.
Luiz H. Tizei, Yoko Iizumi, Toshiya Okazaki, Ryo Nakanishi, Ryo Kitaura, Hisanori Shinohara, Kazu Suenaga. Language： English Publishing type： Research paper scientific journal Publisher： ELSEVIER.
Single atom localization and identification is crucial in understanding effects which depend on the specific local environment of atoms.
In advanced nanometer scale materials, the characteristics of individual atoms may play an important role. Here, we describe spectroscopic experiments electron energy loss spectroscopy, EELS, and Energy Dispersed X-ray spectroscopy, EDX using a low voltage transmission electron microscope designed towards single atom analysis.
For EELS, we discuss the advantages of using lower primary electron energy 30 keV and 60 keV and higher energy losses above eV. The effect of atomic movement is considered. Finally, we discuss the possibility of using atomically resolved EELS and EDX data to measure the fluorescence yield for X-ray emission. C Elsevier BY. Chemical Vapor Deposition Growth of Graphene and Related Materials. Ryo Kitaura, Yasumitsu Miyata, Rong Xiang, James Hone, Jing Kong, Rodney S.
Ruoff, Shigeo Maruyama. JOURNAL OF THE PHYSICAL SOCIETY OF JAPAN Vol. Language： Japanese Publishing type： Research paper scientific journal Publisher： PHYSICAL SOC JAPAN. Research on atomic layers including graphene, hexagonal boron nitride hBN , transition metal dichalcogenides TMDCs and their heterostructures has attracted a great deal of attention. Chemical vapor deposition CVD can provide large-area structure-defined high-quality atomic layer samples, which have considerably contributed to the recent advancement of atomic-layer research.
Kitaura Ryo, Miyata Yasumitsu, Xiang Rong, Hone James, Kong Jing, Ruoff Rodney S. Journal of the Physical Society of Japan Vol. Publishing type： Research paper scientific journal Publisher： Physical Society of Japan. Template Synthesis of Linear-Chain Nanodiamonds Inside Carbon Nanotubes from Bridgehead-Halogenated Diamantane Precursors. Reviewed International journal. Yusuke Nakanishi, Haruka Omachi, Natalie A Fokina, Peter R Schreiner, Ryo Kitaura, Jeremy E P Dahl, Robert M K Carlson, Hisanori Shinohara.
Angewandte Chemie International ed. in English Vol. Publishing type： Research paper scientific journal Publisher： WILEY-V C H VERLAG GMBH. A simple method for the synthesis of linear-chain diamond-like nanomaterials, so-called diamantane polymers, is described.
This synthetic approach is primarily based on a template reaction of dihalogen-substituted diamantane precursors in the hollow cavities of carbon nanotubes. Under high vacuum and in the presence of Fe nanocatalyst particles, the dehalogenated radical intermediates spontaneously form linear polymer chains within the carbon nanotubes. Transmission electron microscopy reveals the formation of well-aligned linear polymers.
We expect that the present template-based approach will enable the synthesis of a diverse range of linear-chain polymers by choosing various precursor molecules.
The present technique may offer a new strategy for the design and synthesis of one-dimensional nanomaterials. Core-level spectroscopy to probe the oxidation state of single europium atoms. Luiz H G Tizei, Ryo Nakanishi, Ryo Kitaura, Hisanori Shinohara, Kazu Suenaga. Physical review letters Vol. The valence of individual europium atoms confined in carbon nanotubes is successfully measured by using core-level electron energy loss spectroscopy. Changes in the oxidation state at the atomic scale have been observed in Eu atomic chains exposed to oxygen.
This indicates that single atoms change their valence state multiple times during the reaction, suggesting that oxidation in confined spaces and with extra energy input from the electron beam might not be a simple one step electron transfer event. Fabrication and optical probing of highly extended, ultrathin graphene nanoribbons in carbon nanotubes. Hong En Lim, Yasumitsu Miyata, Miho Fujihara, Susumu Okada, Zheng Liu, Arifin, Kayoko Sato, Haruka Omachi, Ryo Kitaura, Stephan Irle, Kazu Suenaga, Hisanori Shinohara.
Nanotemplated growth of graphene nanoribbons GNRs inside carbon nanotubes is a promising mean to fabricate ultrathin ribbons with desired side edge configuration. We report the optical properties of the GNRs formed in single-wall carbon nanotubes.
Their optical responses are probed through the diazonium-based side-wall functionalization, which effectively suppresses the excitonic absorption peaks of the nanotubes without damaging the inner GNRs. Differential absorption spectra clearly show two distinct peaks around 1. These peaks are assigned to the optical transitions between the van Hove singularities in the density of state of the GNRs in qualitative agreement with the first-principles calculations.
Resonance Raman spectra and transmission electron microscope observations also support the formation of long GNRs. Minimal inflammogenicity of pristine single-wall carbon nanotubes. Shinya Toyokuni, L I Jiang, Ryo Kitaura, Hisanori Shinohara. Nagoya journal of medical science Vol. Carbon nanotubes CNTs are a novel synthetic material comprising only carbon atoms.
Based on its rigidity, its electrical and heat conductivity and its applicability to surface manufacturing, this material is expected to have numerous applications in industry.
However, due to the material's dimensional similarity to asbestos fibers, its carcinogenicity was hypothesized during the last decade, and indeed, we have shown that multi-wall CNTs MWCNTs of 50 nm in diameter are potently carcinogenic to mesothelial cells after intraperitoneal injection.
Additionally, we suggested that inflammogenicity after intraperitoneal injection can predict mesothelial carcinogenesis. However, few data have been published on the intraperitoneal inflammogenicity of single-wall CNTs SWCNTs. Here, we conducted a series of studies on SWCNTs using both intraperitoneal injection into rats and MeT5A mesothelial cells.
MWCNTs of 50 nm in diameter were used as a positive control, and tangled MWCNTs of 15 nm in diameter were used as a negative control. The results suggest that SWCNTs are a low-risk material with respect to mesothelial carcinogenesis.
Toyokuni S, Jiang LI, Kitaura R, Shinohara H. Shinya Toyokuni, Li Jiang, Ryo Kitaura, Hisanori Shinohara. NAGOYA JOURNAL OF MEDICAL SCIENCE Vol. Language： English Publishing type： Research paper scientific journal Publisher： NAGOYA UNIV, SCH MED. However, due to the material's dimensional similarity to asbestos fibers, its carcinogenicity was hypothesized during the last decade, and indeed, we have shown that multi- wall CNTs MWCNTs of 50 nm in diameter are potently carcinogenic to mesothelial cells after intraperitoneal injection.
The results suggest that SWCNTs are a low- risk material with respect to mesothelial carcinogenesis. Toyokuni Shinya, Jiang Li, Kitaura Ryo, Shinohara Hisanori. Comparison of the acute effects of right ventricular apical pacing and biventricular pacing in patients with heart failure. Kanzaki H, Satomi K, Noda T, Shimizu W, Kamakura S, Kitaura Y, Ishizaka N, Kitakaze M.
Internal medicine Tokyo, Japan Vol. Synthesis and TEM structural characterization of Cflattened carbon nanotube nanopeapods Reviewed. Qing Wang, Ryo Kitaura, Yuta Yamamoto, Shigeo Arai, Hisanori Shinohara. NANO RESEARCH Vol. Language： Japanese Publishing type： Research paper scientific journal Publisher： TSINGHUA UNIV PRESS. A fully flattened carbon nanotube FNT , a graphene nanoribbon GNR analogue, provides a hollow space at edges for endohedral doping.
Due to the unique shape of the hollow space of FNTs, novel types of low-dimensional arrangements of atoms and molecules can be obtained through endohedral doping into FNTs, which provides a new type of nanopeapods. FNT-based nanopeapods have been synthesized through endohedral doping of C, and their structural characterization with transmission electron microscopy TEM performed.
The doping of C into the inner hollow space of FNTs has been carried out via the gas-phase filling method, where open-ended FNTs are sealed in a glass ampoule and heated at K for two days. TEM observations show that most of the encapsulated C molecules align as single molecular chains along the edges of FNTs and that some of the C forms two-dimensional close-packed structures inside FNTs.
Drastic Change in Photoluminescence Properties of Graphene Quantum Dots by Chromatographic Separation. Naoto Fuyuno, Daichi Kozawa, Yuhei Miyauchi, Shinichiro Mouri, Ryo Kitaura, Hisanori Shinohara, Toku Yasuda, Naoki Komatsu, Kazunari Matsuda.
ADVANCED OPTICAL MATERIALS Vol. Graphene quantum dots GQDs have attracted a great deal of interest from the viewpoints of both fundamental studies and applications. Photoluminescence PL is one of the intriguing properties of GQDs, however, the mechanism of the PL in GQDs is not fully understood.
In the present study, a drastic change in the PL from UV to red light region is reported among GQDs separated by size-exclusion high performance liquid chromatography. It is confirmed by transmission electron microscopy images that the GQDs are separated by the difference in their overall sizes. Two-dimensional PL excitation spectra of the chromatographically separated GQDs show four distinct emission peaks at approximate to , approximate to , approximate to , and approximate to nm.
The dominant luminescence features of the separated GQDs show discrete changes depending on the overall size of GQDs, indicating that the PL variation occurs because of differences in density, shape, and size of sp 2 fragments available in the GQDs. Rayleigh scattering studies on inter-layer interactions in structure-defined individual double-wall carbon nanotubes.
Zhao SH. NANO RESEARCH page： Rayleigh scattering studies on inter-layer interactions in structure-defined individual double-wall carbon nanotubes Reviewed. Sihan Zhao, Tomoya Kitagawa, Yuhei Miyauchi, Kazunari Matsuda, Hisanori Shinohara, Ryo Kitaura. Although the inter-layer coupling in layered materials has attracted considerable interest due to its importance in determining physical properties of two-dimensional systems, studies on the inter-layer coupling in one-dimensional systems have so far been limited.
Double-wall carbon nanotubes DWCNTs are one of the most fundamental and ideal model systems to study the inter-layer coupling in one-dimensional systems. In this work, Rayleigh scattering spectroscopy and transmission electron microscopy are used to characterize the electronic transition between inner-and outer-nanotubes of the exactly same individual DWCNT. We find that the inter-layer coupling is strong, leading to downshifts in most of the optical transition energies up to similar to 0.
We also find that the presence of metallic tubes lead to stronger shifts. The inter-layer screening of Coulomb interactions is one of the key factors in explaining the observed results.
Zhiyong Wang, Ryo Kitaura, Hisanori Shinohara. The unstable fullerene I-h-C can be stabilized greatly by encapsulation of two rare-earth metal atoms in its interior. Density functional calculations demonstrate that La-2 I-h,-C has a closed-shell configuration, whereas Y-2 l h -C has a triplet ground state.
Unlike La-2 I-h,-C with a high stability, Y-2 l h -C is found to be a highly reactive radical due to the unpaired electron distributed on the fullerene cage. Such characteristic properties of La-2 I-h,-C and Y-2 l h -C originate from the different energy levels of the metal-based molecular orbitals. Y-2 l h -C can be stabilized, however, through exterior functionalization with a CF3 group. Interestingly, metallofullerenes Gd-2 I-h,-C and Lu-2 I-h,-C have similar frontier molecular orbitals and chemical stabilities to those of Y-2 I-h,-C Direct observation of zipper-like wall-to-wall coalescence of double-wall carbon nanotubes Reviewed.
Sihan Zhao, Yasumitsu Miyata, Hisanori Shinohara, Ryo Kitaura. CARBON Vol. Language： Japanese Publishing type： Research paper scientific journal Publisher： PERGAMON-ELSEVIER SCIENCE LTD.
In situ transmission electron microscope TEM observation has become a fairly powerful characterization method to uniquely provide the real-time information on the dynamics and kinetics of physical and chemical transformations at the nanometer scale. Here, we report a development of a high-temperature-compatible specimen heating holder equipped with a micro-sized carbon nanotube CNT network heater.
This has directly led to a real-time imaging of a purely thermally-driven nano-welding process between two parallel-aligned double-wall carbon nanotubes DWCNTs using low-voltage TEM 80 keV ; a single larger-diameter DWCNT was formed after the reaction and the reaction rate was determined. C Elsevier Ltd. Microporous structures having phenylene fin: Significance of substituent groups for rotational linkers in coordination polymers Reviewed.
Ryotaro Matsuda, Wataru Kosaka, Ryo Kitaura, Yoshiki Kubota, Masaki Takata, Susumu Kitagawa. Language： English Publishing type： Research paper scientific journal Publisher： ELSEVIER SCIENCE BV. Microporous coordination polymers having various shaped apertures were synthesized and crystallographically characterized using substituted terephthalate ligands. The substituents exert a notable influence on the channel size and shape depending on the orientations and disordering of the phenylene units such as a fin.
This is a new aspect of porous coordination polymers, which would provide important information for a precise design of the micropore. C Elsevier Inc. Structure of Tm-2 and Tm2C2 encapsulated in low-symmetry C C-s 6 fullerene cage by single crystal X-ray diffraction Reviewed. Yuki Sado, Shinobu Aoyagi, Noriko Izumi, Ryo Kitaura, Tim Kowalczyk, Jian Wang, Stephan Irle, Eiji Nishibori, Kunihisa Sugimoto, Hisanori Shinohara. Publishing type： Research paper scientific journal Publisher： ELSEVIER SCIENCE BV.
The molecular structures of Tm-2 C C-s 6 and Tm2C2 C C-s 6 are determined by means of single crystal X-ray diffraction using the co-crystals with nickel octaethylporphyrin Ni OEP.
The molecular orientations and Tm positions of Tm-2 C C-s 6 and Tm2C2 C C-s 6 are basically the same each other. One of the two Tm positions is very close to the Tm position of Tm C C-s 6. These facts demonstrate that the stable endohedral Tm positions are not fundamentally affected by the addition of the other Tm atoms but dependent on the kind of the fullerene cage structure. Size-selective complexation and extraction of endohedral metallofullerenes with cycloparaphenylene.
Yusuke Nakanishi, Haruka Omachi, Sanae Matsuura, Yasumitsu Miyata, Ryo Kitaura, Yasutomo Segawa, Kenichiro Itami, Hisanori Shinohara. A new strategy for the non-chromatographic extraction of metallofullerenes from solutions of arc-processed raw soot is based on the size-selective complexation with cycloparaphenylene CPP.
This approach should open new opportunities in metallofullerene chemistry, including for the bulk extraction of metallofullerenes. Kobayashi Keita, Kitaura Ryo, Sasaki Katsuhiro, Kuroda Kotaro, Saito Takeshi, Shinohara Hisanori. Language： Japanese Publishing type： Research paper scientific journal Publisher： The Japan Institute of Metals and Materials. The AuNW drifts significantly within the SWCNT during the reduction. Metal catalyst-free mist flow chemical vapor deposition growth of single-wall carbon nanotubes using C colloidal solutions Reviewed.
Yun Sun, Ryo Kitaura, Jinying Zhang, Yasumitsu Miyata, Hisanori Shinohara. Metal catalyst-free mist flow chemical vapor deposition CVD growth of single-walled carbon nanotubes SWCNTs with C fullerenes has been investigated by using an aqueous colloidal C solution. Under the optimum reaction condition, relatively uniform SWCNTs with a mean diameter of 1. Cap opening, nucleation and the growth of SWCNTs have been occurring almost simultaneously during the present CVD.
C can be used as the seeds i. Furthermore, the coalescence of C caps into a larger one leads to the growth of SWCNTs with larger diameters. Synthesis of refractory conductive niobium carbide nanowires within the inner space of carbon nanotube templates Reviewed.
Keita Kobayashi, Ryo Kitaura, Qing Wang, Ikuya Wakamori, Hisanori Shinohara, Satoshi Anada, Takeshi Nagase, Takeshi Saito, Masaharu Kiyomiya, Hidehiro Yasuda. Conductive niobium carbide NbC nanowires with diameters of nm were synthesized within the inner space of carbon nanotubes CNTs by exposing the CNTs to niobium V chloride vapor through hydrogen reduction. The NbC nanowires were found to have a NaCl-type crystal structure by transmission electron microscopy and transmission electron diffractometry.
Results from electronic transport measurements imply that the electrical conductivity of the synthesized product was improved compared with that of empty CNTs. A cubic dipole lattice of water molecules trapped inside carbon cages.
Shinobu Aoyagi, Norihisa Hoshino, Tomoyuki Akutagawa, Yuki Sado, Ryo Kitaura, Hisanori Shinohara, Kunihisa Sugimoto, Rui Zhang, Yasujiro Murata. Chemical communications Cambridge, England Vol. Publishing type： Research paper scientific journal Publisher： ROYAL SOC CHEMISTRY.
We report the crystal structure and dielectric properties of a pure H2O C60 crystal at low temperature. The caged water molecules free from the hydrogen bonds rotate even at 8 K.
The antifreeze rotating water molecules respond to an external electric field due to their permanent dipole moment.
Observation and Characterization of Fragile Organometallic Molecules Encapsulated in Single-Wall Carbon Nanotubes Reviewed.
Daisuke Ogawa, Ryo Kitaura, Takeshi Saito, Shinobu Aoyagi, Eiji Nishibori, Makoto Sakata, Tetsuya Nakamura, Hisanori Shinohara.
Thermally fragile tris eta 5 -cyclopentadienyl erbium ErCp3 molecules are encapsulated in single-wall carbon nanotubes SWCNTs with high yield. We realized the encapsulation of ErCp3 with high filling ratio by using high quality SWCNTs at an optimized temperature under higher vacuum.
Structure determination based on high-resolution transmission electron microscope observations together with the image simulations reveals the presence of almost free rotation of each ErCp3 molecule in SWCNTs.
The encapsulation is also confirmed by X-ray diffraction. Trivalent character of Er ions i. Missing Small-Bandgap Metallofullerenes: Their Isolation and Electronic Properties Reviewed International journal. Zhiyong Wang, Yusuke Nakanishi, Shoko Noda, Hiroyuki Niwa, Jinying Zhang, Ryo Kitaura, Hisanori Shinohara. Growth of carbon nanotubes via twisted graphene nanoribbons Reviewed. Hong En Lim, Yasumitsu Miyata, Ryo Kitaura, Yoshifumi Nishimura, Yoshio Nishimoto, Stephan Irle, Jamie H.
Warner, Hiromichi Kataura, Hisanori Shinohara. Carbon nanotubes have long been described as rolled-up graphene sheets. It is only fairly recently observed that longitudinal cleavage of carbon nanotubes, using chemical, catalytical and electrical approaches, unzips them into thin graphene strips of various widths, the so-called graphene nanoribbons. In contrast, rolling up these flimsy ribbons into tubes in a real experiment has not been possible.
Theoretical studies conducted by Kit et al. recently demonstrated the tube formation through twisting of graphene nanoribbon, an idea very different from the rolling-up postulation. Here we report the first experimental evidence of a thermally induced self-intertwining of graphene nanoribbons for the preferential synthesis of 7, 2 and 8, 1 tubes within parent-tube templates.
Through the tailoring of ribbon's width and edge, the present finding adds a radically new aspect to the understanding of carbon nanotube formation, shedding much light on not only the future chirality tuning, but also contemporary nanomaterials engineering. Perfectly Ordered Two-Dimensional Layer Structures Found in Some Endohedral Metallofullerenes.
Sachiko Maki, Eiji Nishibori, Yutaka Kitamura, Ryo Kitaura, Masayuki Ishihara, Takayuki Aono, Shinobu Aoyagi, Masaki Takata, Makoto Sakata, Hisanori Shinohara. The determined crystal is a 2D layered structure, which is composed of metallofullerene layers sandwiched by the toluene layers. Although the M C I arrangement in a crystal is almost identical to that of M2Cy C III , the M C I arrangement in a crystal is different from M,Cy C III.
It is found that the difference of the molecular arrangement strongly correlates with an orientation of metallofullerenes in a 2D layer.
Rapid Single-Stage Separation of Micrometer-Long and High-Purity Semiconducting Carbon Nanotubes by Gel Filtration. Thendie Boanerges, Miyata Yasumitsu, Kitaura Ryo, MIYAUCHI Yuhei, MATSUDA Kazunari, SHINOHARA Hisanori. Applied physics express Vol. Publishing type： Research paper scientific journal Publisher： Japan Society of Applied Physics.
Rapid single-stage separation of micrometer-long and high-purity semiconducting carbon nanotubes by gel filtration Reviewed. Boanerges Thendie, Yasumitsu Miyata, Ryo Kitaura, Yuhei Miyauchi, Kazunari Matsuda, Hisanori Shinohara. Applied Physics Express Vol. We demonstrate the separation of high-purity, long semiconducting single-wall carbon nanotubes s-SWCNTs by single-stage gel filtration.
Semiconducting SWCNTs are preferentially adsorbed on an allyl dextran-based gel column and then eluted with surfactant solution at a rate that depends on nanotube length as well as electronic type of nanotubes. These differences allow the separation of length-sorted and purity-enhanced s-SWCNTs by fractionated collection of the eluate, which provides the desired nanotubes for electronic device applications.
STM and STS Studies on the Density of States Modulation of Pr C and Sc3C2 C Binary-Metallofullerene Peapods. Yuki Iijima, Kazunori Ohashi, Naoki Imazu, Ryo Kitaura, Ken Kanazawa, Atsushi Taninaka, Osamu Takeuchi, Hidemi Shigekawa, Hisanori Shinohara. The density of states modulation of single-wall carbon nanotubes SWCNTs is induced by the encapsulation of two different kinds of metallofullerenes Pr C and Sc3C2 C The metallofullerene molecules in SWCNTs strongly affect the local band structures of SWCNTs.
The present findings show that the local electronic structures of SWCNTs can be modified by not only varying the geometric structures of SWCNTs but also the varieties of metallofullerenes encapsulated. Fabrication and Characterization of Fully Flattened Carbon Nanotubes: A New Graphene Nanoribbon Analogue Reviewed. Choi, Q. Wang, Y. Azuma, Y. Majima, J. Warner, Y. Miyata, H. Shinohara, R. Graphene nanoribbons GNR are one of the most promising candidates for the fabrication of graphene-based nanoelectronic devices such as high mobility field effect transistors FET.
Here, we report a high-yield fabrication of a high quality another type of GNR analogue, fully flattened carbon nanotubes flattened CNTs , using solution-phase extraction of inner tubes from large-diameter multi-wall CNTs MWCNTs. Transmission electron microscopy TEM observations show that flattened CNTs have width of typically 20 nm and a barbell-like cross section. Measurements of the low-bias conductance of isolated flattened CNTs as a function of gate voltage shows that the flattened CNTs display ambipolar conduction which is different from those of MWCNTs.
The estimated gap based on temperature dependence of conductivity measurements of isolated flattened CNTs is Structure of Tm C I Metallofullerene by Single-Crystal X-ray Diffraction Using the Co-Crystal with Octaethylporphyrin Nickel Ni OEP. Yuki Sado, Shinobu Aoyagi, Ryo Kitaura, Yasumitsu Miyata, Eiji Nishibori, Hiroshi Sawa, Kunihisa Sugimoto, Hisanori Shinohara.
The molecular structure of Tm C isomer I is revealed by single-crystal X-ray diffraction of the cocrystal with nickel octaethylporphyrin Ni OEP. A rotational movement of Tm C I molecule in the cocrystal is dramatically suppressed by the coordination of two Ni OEP ligands in the cocrystal. The structure of Tm C I in the crystal is explained by the orientation disorder with two different orientations. The so-obtained carbon cage structure is C-5 6 -C The restricted molecular orientations of Tm C I in the cocrystal are achieved by the molecular dipole moment of Tm C 1 that interacts with two Ni OEP ligands.
The present study suggests that the intermolecular interactions can reduce the degree of freedom in the orientation of spherical metallofullerene molecules in the crystals and complexes.
Thin single-wall BN-nanotubes formed inside carbon nanotubes Reviewed. Ryo Nakanishi, Ryo Kitaura, Jamie H. Warner, Yuta Yamamoto, Shigeo Arai, Yasumitsu Miyata, Hisanori Shinohara.
We report a high yield synthesis of single-wall boron nitride nanotubes SWBNNTs inside single-wall carbon nanotubes SWCNTs , a nano-templated reaction, using ammonia borane complexes ABC as a precursor. Transmission electron microscope TEM , high angle annular dark field HAADF -scanning TEM STEM , electron energy loss spectra EELS and high resolution EELS mapping using aberration-corrected TEM system clearly show the formation of thin SWBNNTs inside SWCNTs. We have found that the yield of the SWBNNT formation is high and that the most of ABC molecules decompose and fuse to form the thin BNNTs at a temperature of 1, K having a narrow diameter distribution of 0.
Optical absorption measurements suggest that the band gap of the thin SWBNNTs is about 6. Significance of horizontal propagation of synchronized activities in human epileptic neocortex investigated by optical imaging and immunohistological study.
Hiraishi T, Kitaura H, Oishi M, Fukuda M, Kameyama S, Takahashi H, Kakita A, Fujii Y. Epilepsy research Vol. Evidence of Diamond Nanowires Formed inside Carbon Nanotubes from Diamantane Dicarboxylic Acid Reviewed. Jinying Zhang, Zhen Zhu, Yanquan Feng, Hitoshi Ishiwata, Yasumitsu Miyata, Ryo Kitaura, Jeremy E.
Dahl, Robert M. Carlson, Natalie A. Fokina, Peter R. Schreiner, David Tomanek, Hisanori Shinohara. Ahmadreza Fallah, Yuki Yonetani, Ryosuke Senga, Kaori Hirahara, Ryo Kitaura, Hisanori Shinohara, Yoshikazu Nakayama.
Nanoscale Vol. Sc3N C80 fullerenes are inserted inside carbon nanotubes CNTs. This value is an order of magnitude higher than the threshold of electron-induced damage in C60 molecules. Electron energy loss spectroscopy confirms the presence of Sc atoms in capsules. Chirally selective growth and extraction of single-wall carbon nanotubes via fullerene nano-peapods Reviewed.
Jinying Zhang, Feng Zhou, Yasumitsu Miyata, Ryo Kitaura, Haibin Su, Hisanori Shinohara. RSC ADVANCES Vol. Single-wall carbon nanotubes SWCNTs grown from C and C inside SWCNTs with diameters of 1. The as-produced SWCNTs have been extracted, separated, and characterized.
The products from C are dominated by 7,6 and 9,4 SWCNTs, whereas those from C are dominated by 6,5 SWCNTs. Yun Sun, Ryo Kitaura, Takuya Nakayama, Yasumitsu Miyata, Hisanori Shinohara. NANO Vol. The influences of synthesis parameters on the mean diameter and diameter distribution of as-grown single-wall carbon nanotubes SWCNTs with chemical vapor deposition CVD using the mist flow method have been investigated in detail with Raman spectroscopy, scanning electron microscopy SEM and transmission electron microscopy TEM.
We found that CVD reaction temperature and flow rate play an essential role in controlling the mean diameter and the quality of as-grown SWCNTs. Furthermore, we found that the carbon supply kinetics can be a dominant factor to determine the diameter of as-grown SWCNTs in the present mist flow method. Under a different combination of various parameters, the mean diameter of SWCNTs can be varied from 0. Synthesis and Transformation of Linear Adamantane Assemblies inside Carbon Nanotubes Reviewed.
Jinying Zhang, Yanquan Feng, Hitoshi Ishiwata, Yasumitsu Miyata, Ryo Kitaura, Jeremy E. Carlson, Hisanori Shinohara, David Tomanek. We report the assembly and thermal transformation of linear diamondoid assemblies inside carbon nanotubes. Our calculations and observations indicate that these molecules undergo selective reactions within the narrow confining space of a carbon nanotube.
Upon vacuum annealing of adamantane molecules encapsulated in a carbon nanotube, we observe a sharp Raman feature at cm -1 , which we interpret as a stretching mode of carbon chains formed by thermal conversion of adamantane inside a carbon nanotube. Introduction of pure hydrogen during thermal annealing, however, suppresses the formation of carbon chains and seems to keep adamantane intact.
Topological Difference in 2D Layers Steers the Formation of Rigid and Flexible 3D Supramolecular Isomers: Impact on the Adsorption Properties Reviewed. Prakash Kanoo, Ryotaro Matsuda, Ryo Kitaura, Susumu Kitagawa, Tapas Kumar Maji. INORGANIC CHEMISTRY Vol. Language： English Publishing type： Research paper scientific journal Publisher： AMER CHEMICAL SOC. Starting with the same precursors, pyridine-2,3-dicarboxylate pyrdc and 4,4'-bipyridyl bipy , two 3D porous coordination polymers, [Cu bipy 0.
Single-crystal structure analysis revealed that 1 and 2 are supramolecular isomers with 3D pillared-layer structures having 1D channel systems. Isomer 1 has a flexible structure and shows gated adsorption behavior, while framework 2 has a rigid backbone and exhibits the adsorption properties of typical microporous materials.
Yasumitsu Miyata, Eriko Maeda, Keiichi Kamon, Ryo Kitaura, Yuki Sasaki, Shoji Suzuki, Hisanori Shinohara. Publishing type： Research paper scientific journal Publisher： JAPAN SOC APPLIED PHYSICS. The synthesis of graphene and hexagonal boron nitride hBN hybrid sheets has been achieved using a two-step chemical vapor deposition CVD process. Individual grains of single-layer graphene are grown from methane, and hBN is, then, synthesized from ammonia borane on the same copper Cu foil.
Optical absorption and Raman measurements reveal that the hBN is formed on the bare surface of Cu foil and the graphene grains play a crucial role as an inactive protective layer of Cu foil for the ammonia borane CVD. Furthermore, the hBN growth is found to be initiated preferentially by the edge of graphene grains.
Dimerization-Initiated Preferential Formation of Coronene-Based Graphene Nanoribbons in Carbon Nanotubes. Miho Fujihara, Yasumitsu Miyata, Ryo Kitaura, Yoshifumi Nishimura, Cristopher Camacho, Stephan Irle, Yoko Iizumi, Toshiya Okazaki, Hisanori Shinohara. We have investigated the growth mechanism of coronene-derived graphene nanoribbons GNRs using two different precursors: coronene and a dimer form of coronene, so-called dicoronylene C48H For both of the precursors, the formation of nanoribbon-like materials inside carbon nanotubes CNTs was confirmed by transmission electron microscope observations.
Experimental and theoretical Raman analysis reveals that the samples also encapsulated dicoronylene and linearly condensed other coronene oligomers, which can be regarded as analogues to GNRs. Interestingly, it was found that the present doping condition of coronene yields dicoronylene prior to encapsulation due to the thermal dimerization of coronene. These results indicate that the dimerization before the encapsulation drives the preferential formation of the coronene-based GNRs within CNTs.
Preparation and Observation of an Atomic Layer of Gold Formed on the Surface of Graphene. Sasaki Yuki, Kitaura Ryo, Yamamoto Yuta, ARAI Shigeo, SUZUKI Shoji, MIYATA Yasumitsu, SHINOHARA Hisanori. Preparation and Observation of an Atomic Layer of Gold Formed on the Surface of Graphene Reviewed. Yuki Sasaki, Ryo Kitaura, Yuta Yamamoto, Shigeo Arai, Shoji Suzuki, Yasumitsu Miyata, Hisanori Shinohara.
Freestanding clean graphene is prepared using graphene samples grown by chemical vapor deposition and direct transfer onto a SiN grid followed by hydrogen plasma treatment. High-resolution transmission electron microscopy has shown that the Au atoms deposited on the graphene possess a unique layer structure with a square arrangement of Au atoms.
We found that the Au nanostructure vaporizes under mild electron beam irradiation conditions, which is specific to the unique thin layer structure. Rock-Salt-Type Crystal of Thermally Contracted C60 with Encapsulated Lithium Cation Reviewed.
Shinobu Aoyagi, Yuki Sado, Eiji Nishibori, Hiroshi Sawa, Hiroshi Okada, Hiromi Tobita, Yasuhiko Kasama, Ryo Kitaura, Hisanori Shinohara. Dimerization-Initiated Preferential Formation of Coronene-Based Graphene Nanoribbons in Carbon Nanotubes Reviewed.
Fujihara, Miho; Miyata, Yasumitsu; Kitaura, Ryo; et al. Journal of Physical Chemistry C Vol. Nakanishi, Ryo; Kitaura, Ryo; Ayala, Paola; et al. Physical Review B Vol. Growth of large-diameter similar to 4 nm single-wall carbon nanotubes in the nanospace of mesoporous material SBA Reviewed.
Keita Kobayashi, Ryo Kitaura, Fumihiro Nishimura, Hirofumi Yoshikawa, Kunio Awaga, Hisanori Shinohara. Publishing type： Research paper scientific journal Publisher： PERGAMON-ELSEVIER SCIENCE LTD.
Single-wall carbon nanotubes SWCNTs have been synthesized by supported-catalyst chemical vapor deposition CCVD using one-dimensional 1D channels of mesoporous silica SBA; mean channel diameter, 6.
The synthesized SWCNTs have much larger diameters than the SWCNTs synthesized by conventional CCVD. Large metal particles formed in the channels should play an important role in the growth of the SWCNTs with larger diameters. Length-Sorted Semiconducting Carbon Nanotubes for High-Mobility Thin Film Transistors Reviewed. Yasumitsu Miyata, Kazunari Shiozawa, Yuki Asada, Yutaka Ohno, Ryo Kitaura, Takashi Mizutani, Hisanori Shinohara. Publishing type： Research paper scientific journal Publisher： TSINGHUA UNIV PRESS.
We have developed a process for chemical purification of carbon nanotubes for solution-processable thin-film transistors TFTs having high mobility. Films of the purified carbon nanotubes fabricated by simple drop coating showed carrier mobilities as high as cm 2 V -1 s -1 , normalized transconductances of 0. Such high performance requires the preparation of a suspension of micrometer-long and highly purified semiconducting single-walled carbon nanotubes SWCNTs.
Our purification process includes length and electronic-type selective trapping of SWCNTs using recycling gel filtration with a mixture of surfactants.
The results provide an important milestone toward printed high-speed and large-area electronics with roll-to-roll and ink-jet device fabrication. Purity-enhanced bulk synthesis of thin single-wall carbon nanotubes using iron-copper catalysts Reviewed. Lim, Y. Miyata, T. Nakayama, S. Chen, R. Kitaura, H. We report high purity and high yield synthesis of single-wall carbon nanotubes SWCNTs of narrow diameter from iron-copper bimetal catalysts. The SWCNTs with diameter of 0.
Single metal and bimetal catalysts are systematically investigated to achieve both the enhancement of SWCNT yield and the suppression of the undesired formation of graphitic impurities.
The relative yield and purity of SWCNTs are quantified using optical absorption spectroscopy with an ultracentrifuge-based purification technique. For the single metal catalyst, iron shows the highest catalytic activity compared with the other metals such as cobalt, nickel, molybdenum, copper, and platinum.
It has been found that the addition of copper to iron results in the suppression of carbonaceous impurity formation without decreasing the SWCNT yield. The purity-enhanced SWCNT shows fairly low sheet resistance due to the improvement of inter-nanotube contacts.
This scalable design of SWCNT synthesis with enhanced purity is therefore a promising tool for shaping future high performance devices. Growth of Linear Carbon Chains inside Thin Double-Wall Carbon Nanotubes Reviewed.
Zhao, R. Hara, S. Irle, H. Fusion reactions of size-selected linear polyyne molecules, C 10 H 2 , in the ultrathin one-dimensional 1D nanospace of double wall carbon nanotubes DWCNTs have been observed, leading to the formation of very long linear carbon chains. The formation and growth of long linear carbon chains is investigated by Raman spectroscopy and density-functional tight-binding-based molecular dynamics simulations.
The high-resolution transmission electron microscope images of C 10 H 2 DWCNTs show that the encapsulated linear C 10 H 2 molecules have a length of 1.
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