1
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Otsuka H, Urita K, Honma N, Kimuro T, Amako Y, Kukobat R, Bandosz TJ, Ukai J, Moriguchi I, Kaneko K. Transient chemical and structural changes in graphene oxide during ripening. Nat Commun 2024; 15:1708. [PMID: 38402244 PMCID: PMC10894275 DOI: 10.1038/s41467-024-46083-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 02/13/2024] [Indexed: 02/26/2024] Open
Abstract
Graphene oxide (GO)-the oxidized form of graphene-is actively studied in various fields, such as energy, electronic devices, separation of water, materials engineering, and medical technologies, owing to its fascinating physicochemical properties. One major drawback of GO is its instability, which leads to the difficulties in product management. A physicochemical understanding of the ever-changing nature of GO can remove the barrier for its growing applications. Here, we evidencde the presence of intrinsic, metastable and transient GO states upon ripening. The three GO states are identified using a [Formula: see text] transition peak of ultraviolet-visible absorption spectra and exhibit inherent magnetic and electrical properties. The presence of three states of GO is supported by the compositional changes of oxygen functional groups detected via X-ray photoelectron spectroscopy and structural information from X-ray diffraction analysis and transmission electron microscopy. Although intrinsic GO having a [Formula: see text] transition at 230.5 ± 0.5 nm is stable only for 5 days at 298 K, the intrinsic state can be stabilized by either storing GO dispersions below 255 K or by adding ammonium peroxydisulfate.
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Affiliation(s)
- Hayato Otsuka
- Research Initiative for Supra-Materials, Shinshu University, 4-17-1 Wakasato, Nagano, Nagano, 380-8553, Japan
| | - Koki Urita
- Graduate School of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki, Nagasaki, 852-8521, Japan
| | - Nobutaka Honma
- New Material & Value Creation Gr., Project Material Creation Dept., Mobility Material Engineering Div., Toyota Motor Corporation, 1, Toyota-cho, Toyota, Aichi, 471-8572, Japan
| | - Takashi Kimuro
- Development Gr.2, Development Section, Engineering Dept., Sanwayuka Industry Corporation, Fukada 15, Ichiriyamacho, Kariya, Aichi, 448-0002, Japan
| | - Yasushi Amako
- Department of Physics, Faculty of Science, Shinshu University, 3-1-1 Asahi, Matsumoto, Nagano, 390-8621, Japan
| | - Radovan Kukobat
- Research Initiative for Supra-Materials, Shinshu University, 4-17-1 Wakasato, Nagano, Nagano, 380-8553, Japan
- Department of Chemical Engineering and Technology, Faculty of Technology, University of Banja Luka, B.V. Stepe Stepanovica 73, 78 000, Banja Luka, Bosnia and Herzegovina
| | - Teresa J Bandosz
- Department of Chemistry and Biochemistry, The City College of New York, 160 Convent Avenue, New York, NY, 10031, USA
| | - Junzo Ukai
- New Material & Value Creation Gr., Project Material Creation Dept., Mobility Material Engineering Div., Toyota Motor Corporation, 1, Toyota-cho, Toyota, Aichi, 471-8572, Japan
| | - Isamu Moriguchi
- Graduate School of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki, Nagasaki, 852-8521, Japan
| | - Katsumi Kaneko
- Research Initiative for Supra-Materials, Shinshu University, 4-17-1 Wakasato, Nagano, Nagano, 380-8553, Japan.
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2
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Notohara H, Urita K, Moriguchi I. Direct Evidence of Reversible SnO 2-Li Reactions in Carbon Nanospaces. ACS Appl Mater Interfaces 2023. [PMID: 37314754 DOI: 10.1021/acsami.3c02805] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
We present herein that carbon nanospaces are the key reaction space to improve the reversibility of the reaction of SnO2 with Li-ions for lithium-ion batteries, demonstrated by both ex situ and in situ observations using high-resolution scanning transmission electron microscopy with electron energy loss spectroscopy. Conversion-type electrode materials, such as SnO2, undergo large volume changes and phase separation during the charge-discharge process, which lead to degradation in the battery performance. By confining the SnO2-Li reaction within carbon nanopores, the battery performance is improved. However, the exact phase changes of SnO2 in the nanospaces are unclear. By directly observing the electrodes during the charge-discharge process, the carbon walls are capable of preventing the expansion of SnO2 particles and minimizing the conversion-induced phase separation of Sn and Li2O on the sub-nanometer scale. Thus, nanoconfinement structures can effectively improve the reversibility performance of conversion-type electrode materials.
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Affiliation(s)
- Hiroo Notohara
- Graduate School of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
| | - Koki Urita
- Graduate School of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
| | - Isamu Moriguchi
- Graduate School of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
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3
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Ahuja P, Ujjain SK, Kukobat R, Urita K, Moriguchi I, Furuse A, Hattori Y, Fujimoto K, Rao G, Ge X, Wright T, Kaneko K. Air-permeable redox mediated transcutaneous CO 2 sensor. Chem Eng J 2023; 457:141260. [PMID: 36620723 PMCID: PMC9804966 DOI: 10.1016/j.cej.2022.141260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 12/14/2022] [Accepted: 12/30/2022] [Indexed: 06/17/2023]
Abstract
Standard clinical care of neonates and the ventilation status of human patients affected with coronavirus disease involves continuous CO2 monitoring. However, existing noninvasive methods are inadequate owing to the rigidity of hard-wired devices, insubstantial gas permeability and high operating temperature. Here, we report a cost-effective transcutaneous CO2 sensing device comprising elastomeric sponges impregnated with oxidized single-walled carbon nanotubes (oxSWCNTs)-based composites. The proposed device features a highly selective CO2 sensing response (detection limit 155 ± 15 ppb), excellent permeability and reliability under a large deformation. A follow-up prospective study not only offers measurement equivalency to existing clinical standards of CO2 monitoring but also provides important additional features. This new modality allowed for skin-to-skin care in neonates and room-temperature CO2 monitoring as compared with clinical standard monitoring system operating at high temperature to substantially enhance the quality for futuristic applications.
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Affiliation(s)
- Preety Ahuja
- Research Initiative for Supra-Material, Shinshu University, Nagano 380-8553, Japan
- Center for Advanced Sensor Technology and Department of Chemical, Biochemical and Environmental Engineering, University of Maryland, Baltimore County, Baltimore, MD 21250, USA
| | - Sanjeev Kumar Ujjain
- Research Initiative for Supra-Material, Shinshu University, Nagano 380-8553, Japan
- Center for Advanced Sensor Technology and Department of Chemical, Biochemical and Environmental Engineering, University of Maryland, Baltimore County, Baltimore, MD 21250, USA
| | - Radovan Kukobat
- Center for Biomedical Research, Faculty of Medicine, University of Banja Luka, Banja Luka 78000, Bosnia and Herzegovina
| | - Koki Urita
- Graduate School of Engineering, Nagasaki University, Nagasaki 852-8521, Japan
| | - Isamu Moriguchi
- Graduate School of Engineering, Nagasaki University, Nagasaki 852-8521, Japan
| | - Ayumi Furuse
- Research Initiative for Supra-Material, Shinshu University, Nagano 380-8553, Japan
| | - Yoshiyuki Hattori
- Division of Chemistry and Materials, Faculty of Textile Science and Technology, Shinshu University, Ueda 386-8567, Japan
| | - Keisaku Fujimoto
- Omachi Municipal General Hospital, Omachi 398-0002, Japan
- School of Medicine, Shinshu University, Matsumoto 390-8621, Japan
| | - Govind Rao
- Center for Advanced Sensor Technology and Department of Chemical, Biochemical and Environmental Engineering, University of Maryland, Baltimore County, Baltimore, MD 21250, USA
| | - Xudong Ge
- Center for Advanced Sensor Technology and Department of Chemical, Biochemical and Environmental Engineering, University of Maryland, Baltimore County, Baltimore, MD 21250, USA
| | - Thelma Wright
- Department of Anesthesiology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Katsumi Kaneko
- Research Initiative for Supra-Material, Shinshu University, Nagano 380-8553, Japan
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4
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Franklin GF, Balocchi A, Taberna PL, Barnabe A, Barbosa JB, Blei M, Tongay S, Marie X, Urita K, Chane-Ching JY. Mitigation of Edge and Surface States Effects in Two-Dimensional WS 2 for Photocatalytic H 2 Generation. ChemSusChem 2022; 15:e202200169. [PMID: 35230739 DOI: 10.1002/cssc.202200169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 03/01/2022] [Indexed: 06/14/2023]
Abstract
Large scale development of the 2D transition metal di-chalcogenides (TMDC) relies on landmark improvement in performance, which could emerge from nanostructuration. Using p-WS2 nanoflakes with different degrees of exfoliation and fracturing, perspectives were provided to develop high-surface-area 2D p-WS2 films for the photocatalytic hydrogen generation. The critical role of inter-nanoflakes contacts within high-surface-area 2D films was demonstrated, highlighting the benefit of plane/plane versus edge/plane contacts. Evidence of the high density of surface states displayed by these 2D films was provided through electrochemical measurements. In addition to operating as recombination centers, the surface states were shown to give rise to deleterious Fermi-level pinning (FLP), which dramatically decreased the efficiency of charge carrier separation. Lastly, promising strategies yielding FLP suppression via surface states modification were proposed. In particular, use of a multifunctional ultrathin film displaying healing, catalytic, and n-type semiconduction properties was shown to greatly enhance charge carrier separation and transport to the photo-electrode/electrolyte interface. When the 2D photoelectrodes were fabricated with the above prerequisites (i. e., a high proportion of plane/plane contacts and a successful surface states chemical modification), a photocurrent up to 4.5 mA cm-2 was achieved for the first time on 2D p-WS2 photocathodes for hydrogen generation.
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Affiliation(s)
| | - Andrea Balocchi
- Université de Toulouse, INSA-CNRS-UPS, LPCNO, 135 Av. Rangueil, 31077, Toulouse, France
| | - Pierre-Louis Taberna
- UPS, CNRS, CIRIMAT, Université de Toulouse, 118 Route de Narbonne, F-31062, Toulouse, France
| | - Antoine Barnabe
- UPS, CNRS, CIRIMAT, Université de Toulouse, 118 Route de Narbonne, F-31062, Toulouse, France
| | - Juliana Barros Barbosa
- UPS, CNRS, CIRIMAT, Université de Toulouse, 118 Route de Narbonne, F-31062, Toulouse, France
| | - Mark Blei
- School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, Arizona, 85287, USA
| | - Sefaattin Tongay
- School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, Arizona, 85287, USA
| | - Xavier Marie
- Université de Toulouse, INSA-CNRS-UPS, LPCNO, 135 Av. Rangueil, 31077, Toulouse, France
| | - Koki Urita
- Department of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki, 852-8521, Japan
| | - Jean Yves Chane-Ching
- UPS, CNRS, CIRIMAT, Université de Toulouse, 118 Route de Narbonne, F-31062, Toulouse, France
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5
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Fujimori T, Morelos-Gómez A, Zhu Z, Muramatsu H, Futamura R, Urita K, Terrones M, Hayashi T, Endo M, Hong SY, Choi YC, Tománek D, Kaneko K. Publisher Correction: Conducting linear chains of sulphur inside carbon nanotubes. Nat Commun 2022; 13:1179. [PMID: 35228531 PMCID: PMC8885743 DOI: 10.1038/s41467-022-28704-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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6
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Komine Y, Urita K, Notohara H, Moriguchi I. Direct Evidence of Black Phosphorus Formation in Carbon Nanospaces by Quasi-high Pressure Effect. CHEM LETT 2022. [DOI: 10.1246/cl.210644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Yuki Komine
- Graduate School of Engineering, 1-14 Bunkyo-machi, Nagasaki 852-851, Japan
| | - Koki Urita
- Graduate School of Engineering, 1-14 Bunkyo-machi, Nagasaki 852-851, Japan
| | - Hiroo Notohara
- Graduate School of Engineering, 1-14 Bunkyo-machi, Nagasaki 852-851, Japan
| | - Isamu Moriguchi
- Graduate School of Engineering, 1-14 Bunkyo-machi, Nagasaki 852-851, Japan
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7
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Notohara H, Urita K, Moriguchi I. Reduction of external pressure on all‐solid‐state battery using SnO
2
‐embedded porous carbon by CNT assistance. Nano Select 2021. [DOI: 10.1002/nano.202100042] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Affiliation(s)
- Hiroo Notohara
- Graduate School of Engineering Nagasaki University Nagasaki Japan
| | - Koki Urita
- Graduate School of Engineering Nagasaki University Nagasaki Japan
| | - Isamu Moriguchi
- Graduate School of Engineering Nagasaki University Nagasaki Japan
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8
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Kimura J, Ohkubo T, Nishina Y, Urita K, Kuroda Y. Adsorption enhancement of nitrogen gas by atomically heterogeneous nanospace of boron nitride. RSC Adv 2020; 11:838-846. [PMID: 35423671 PMCID: PMC8693509 DOI: 10.1039/d0ra08437a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Accepted: 12/14/2020] [Indexed: 11/21/2022] Open
Abstract
In this study, porous boron nitride (p-BN) with hexagonal phase boron nitride (h-BN) pore walls was synthesized using high-temperature calcination. Negligible variation in pore-wall structure can be observed in powder X-ray diffraction (XRD) profiles and infrared (IR) spectra. However, a highly stable p-BN with a stable pore structure even at 973 K under the oxidative conditions is obtained when synthesized at higher than 1573 K under nitrogen gas flow. For p-BN, this stability is obtained by generating h-BN microcrystals. Nitrogen adsorption–desorption isotherms at 77 K provide type-IV features and typical adsorption–desorption hysteresis, which suggests micropore and mesopore formation. Moreover, adsorption–desorption isotherms of Ar at 87 K are measured and compared with those of nitrogen. The relative adsorbed amount of nitrogen (i.e., the amount of nitrogen normalized by that of Ar at each relative pressure or adsorption potential value) on p-BN is considerably larger than that on microporous carbon at low-pressure regions, which suggests the existence of strong adsorption sites on the p-BN surface. In fact, the relative number of adsorbed nitrogen molecules to that of Ar on p-BN is, at most, 150%–200% larger than that on microporous carbon for the same adsorption potential state. Furthermore, additional adsorption enhancement to nitrogen between P/P0 = 10−5 and 10−3 can be observed for p-BN treated at 1673 K, which suggests the uniformly adsorbed layer formation of nitrogen molecules in the vicinity of a basal planar surface. Thus, unlike typical nanoporous sp2 carbons, p-BN materials have the potential to enhance adsorption for certain gas species because of their unique surface state. Porous BN with atomically heterogeneous surfaces can more strongly adsorb dinitrogen molecules than typical porous carbon materials.![]()
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Affiliation(s)
- Jun Kimura
- Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University 3-1-1 Tsushimanaka, Kita-ku Okayama 700-8530 Japan
| | - Takahiro Ohkubo
- Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University 3-1-1 Tsushimanaka, Kita-ku Okayama 700-8530 Japan
| | - Yuta Nishina
- Research Core for Interdisciplinary Sciences, Okayama University 3-1-1 Tsushimanaka, Kita-ku Okayama 700-8530 Japan
| | - Koki Urita
- Graduate School of Engineering, Nagasaki University 1-14 Bunkyo-machi Nagasaki Nagasaki 852-8521 Japan
| | - Yasushige Kuroda
- Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University 3-1-1 Tsushimanaka, Kita-ku Okayama 700-8530 Japan
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9
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Wang J, Okabe J, Urita K, Moriguchi I, Wei M. Cu2S hollow spheres as an anode for high-rate sodium storage performance. J Electroanal Chem (Lausanne) 2020. [DOI: 10.1016/j.jelechem.2020.114523] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Notohara H, Urita K, Moriguchi I. SnO 2-Embedded Nanoporous Carbon Electrode with a Reaction-Buffer Space for Stable All-Solid-State Li Ion Batteries. ACS Appl Mater Interfaces 2020; 12:43042-43048. [PMID: 32845123 DOI: 10.1021/acsami.0c09792] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The conventional approach for fabricating all-solid-state batteries has required a highly dense layer of electrode and electrolyte. Their close contact interface is not suitable for alloy- or conversion-based active materials because their large volume change in lithiation/delithiation reactions causes a collapse of the contact interface or reaction limitations under mechanical constriction. In this study, we propose that a SnO2-embedded porous carbon electrode shows high cyclability and high capacity even at high constraint pressure owing to the nanopores, which work as a buffer space for the large volume change accompanied with SnO2-Sn conversion reaction and Sn-Li alloying-dealloying reaction. A detailed investigation between structural parameters of the electrode material and charge-discharge properties revealed Li ion conduction in carbon nanopores from a solid electrolyte located outside as well as the optimal conditions to yield high performance. SnO2-loading (75 wt %) in carbon nanopores, which provides the buffer space corresponding to the inevitable volume expansion by full lithiation, brought out an excellent performance at room temperature superior to that in an organic liquid electrolyte system: a high capacity of 1023 mAh/g-SnO2 at 50 mA/g, high capacity retention of 97% at 300th cycle at 300 mA/g, and high rate capability with over 75% capacity retention at 1000 against 50 mA/g, whose values are also superior to the system using the organic liquid electrolyte.
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Affiliation(s)
- Hiroo Notohara
- Graduate School of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
| | - Koki Urita
- Graduate School of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
| | - Isamu Moriguchi
- Graduate School of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
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11
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Urita C, Urita K, Araki T, Horio K, Yoshida M, Moriguchi I. New insights into the heat of adsorption of water, acetonitrile, and n-hexane in porous carbon with oxygen functional groups. J Colloid Interface Sci 2019; 552:412-417. [PMID: 31151018 DOI: 10.1016/j.jcis.2019.05.090] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2019] [Revised: 05/24/2019] [Accepted: 05/26/2019] [Indexed: 11/29/2022]
Abstract
Isosteric heat of adsorption is exquisitely sensitive to structural changes in carbon surfaces based on the energetic behavior of the interactions between adsorbates and carbon materials. We discuss the relationships between porous structures, oxygen functional groups, and heat of adsorption based on the behavior of the heat of adsorption of polar and non-polar fluids on porous carbon materials with oxygen functional groups. The porosity and functional groups of porous carbon materials were estimated from N2 adsorption isotherms at 77 K and temperature-programmed desorption. High-resolution adsorption isotherms of water, acetonitrile (polar fluid), and n-hexane (non-polar fluid) were measured on porous carbon materials with different pore size distributions and amounts of oxygen functional groups at various temperatures. The heats of adsorption were determined by applying the Clausius-Clapeyron equation to the adsorption isotherms. The heat of adsorption curves directly reflect the effects of interactions of fluid-oxygen functional groups, fluid-basal planes of pore walls, and fluid-fluid interfaces. In particular, the heat of adsorption curve of water is very sensitive to surface oxygen functional groups. This finding indicates the possibility of estimating the relative amounts of oxygen functional groups on porous carbon materials based on the amounts of water adsorbed at specific relative pressures.
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Affiliation(s)
- Chiharu Urita
- Graduate School of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
| | - Koki Urita
- Graduate School of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan.
| | - Takuya Araki
- Graduate School of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
| | - Keiji Horio
- MicrotracBEL Corp., 8-2-52 Nanko-Higashi, Suminoe-ku, Osaka 559-0031, Japan
| | - Masayuki Yoshida
- MicrotracBEL Corp., 8-2-52 Nanko-Higashi, Suminoe-ku, Osaka 559-0031, Japan
| | - Isamu Moriguchi
- Graduate School of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
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12
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Chotimah N, Putri AD, Ono Y, Kento S, Hattori Y, Wang S, Futamura R, Urita K, Vallejos-Burgos F, Moriguchi I, Morimoto M, Cimino RT, Neimark AV, Sakai T, Kaneko K. Nanoporosity Change on Elastic Relaxation of Partially Folded Graphene Monoliths. Langmuir 2017; 33:14565-14570. [PMID: 29178804 DOI: 10.1021/acs.langmuir.7b03328] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Fabrication of nanographene shows a promising route for production of designed porous carbons, which is indispensable for highly efficient molecular separation and energy storage applications. This process requires a better understanding of the mechanical properties of nanographene in their aggregated structure. We studied the structural and mechanical properties of nanographene monoliths compressed at 43 MPa over different times from 3 to 25 h. While in monoliths compressed over shorter time adsorption isotherms of Ar at 87 K or N2 at 77 K exhibited a prominent hysteresis due to presence of predominant mesopores, compression for long time induces a low pressure hysteresis. On the other hand, compression for 25 h increases the microporosity evaluated by Ar adsorption, not by N2 adsorption, indicating that 25 h compression rearranges the nanographene stacking structure to produce ultramicropores that can be accessible only for Ar. TEM, X-ray diffraction, and Raman spectroscopic studies indicated that the compression for 25 h unfolds double-bent-like structures, relaxing the unstable nanographene stacked structure formed on the initial compression without nanographene sheets collapse. This behavior stems from the highly elastic nature of the nanographenes.
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Affiliation(s)
| | | | | | - Sagisaka Kento
- Division of Chemistry and Materials, Faculty of Textile Science and Technology, Shinshu University , Ueda 386-8567, Japan
| | - Yoshiyuki Hattori
- Division of Chemistry and Materials, Faculty of Textile Science and Technology, Shinshu University , Ueda 386-8567, Japan
| | | | | | - Koki Urita
- Department of Applied Chemistry, Faculty of Engineering, Nagasaki University , Nagasaki 852-8521, Japan
| | | | - Isamu Moriguchi
- Department of Applied Chemistry, Faculty of Engineering, Nagasaki University , Nagasaki 852-8521, Japan
| | | | - Richard T Cimino
- Department of Chemical and Biochemical Engineering, Rutgers, The State University of New Jersey , Rutgers, New Jersey 08854-8058, United States
| | - Alexander V Neimark
- Department of Chemical and Biochemical Engineering, Rutgers, The State University of New Jersey , Rutgers, New Jersey 08854-8058, United States
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13
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Pina-Salazar EZ, Urita K, Hayashi T, Futamura R, Vallejos-Burgos F, Włoch J, Kowalczyk P, Wiśniewski M, Sakai T, Moriguchi I, Terzyk AP, Osawa E, Kaneko K. Water Adsorption Property of Hierarchically Nanoporous Detonation Nanodiamonds. Langmuir 2017; 33:11180-11188. [PMID: 28793776 DOI: 10.1021/acs.langmuir.7b02046] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The detonation nanodiamonds form the aggregate having interparticle voids, giving a marked hygroscopic property. As the relationship between pore structure and water adsorption of aggregated nanodiamonds is not well understood yet, adsorption isotherms of N2 at 77 K and of water vapor at 298 K of the well-characterized aggregated nanodiamonds were measured. HR-TEM and X-ray diffraction showed that the nanodiamonds were highly crystalline and their average crystallite size was 4.5 nm. The presence of the graphitic layers on the nanodiamond particle surface was confirmed by the EELS examination. The pore size distribution analysis showed that nanodiamonds had a few ultramicropores with predominant mesopores of 4.5 nm in average size. The water vapor adsorption isotherm of IUPAC Type V indicates the hydrophobicity of the nanodiamond aggregates, with the presence of hydrophilic sites. Then the hygroscopic nature of nanodiamonds should be associated with the surface functionalities of the graphitic shell and the ultramicropores on the mesopore walls.
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Affiliation(s)
| | - Koki Urita
- Division of Chemistry and Materials Science, Graduate School of Engineering, Nagasaki University , Nagasaki 852-8521, Japan
| | | | | | | | - Jerzy Włoch
- Faculty of Chemistry, Synthesis and Modification of Carbon Materials Research Group, Nicolaus Copernicus University in Toruń , Gagarin Street 7, 87-100 Toruń, Poland
| | - Piotr Kowalczyk
- School of Engineering and Information Technology, Murdoch University , Murdoch 6150, WA, Australia
| | - Marek Wiśniewski
- Faculty of Chemistry, Physicochemistry of Carbon Materials Research Group, Nicolaus Copernicus University in Toruń , Gagarin Street 7, 87-100 Toruń, Poland
- INVEST-TECH R&D Center, Plaska Street 32-34, 87-100 Toruń, Poland
| | | | - Isamu Moriguchi
- Division of Chemistry and Materials Science, Graduate School of Engineering, Nagasaki University , Nagasaki 852-8521, Japan
| | - Artur P Terzyk
- Faculty of Chemistry, Physicochemistry of Carbon Materials Research Group, Nicolaus Copernicus University in Toruń , Gagarin Street 7, 87-100 Toruń, Poland
| | - Eiji Osawa
- Nano-Carbon Research Institute, Ltd., Ueda, Nagano 386-8567, Japan
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14
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Urita K, Urita C, Fujita K, Horio K, Yoshida M, Moriguchi I. The ideal porous structure of EDLC carbon electrodes with extremely high capacitance. Nanoscale 2017; 9:15643-15649. [PMID: 28993824 DOI: 10.1039/c7nr05307j] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We propose an ideal porous structure of carbon electrodes for electric double-layer capacitors (EDLCs). The porous carbon successfully improved the gravimetric capacitance above ∼200 F g-1 even in an organic electrolyte by utilizing the carbon nanopore surface more effectively. High-resolution transmission electron microscopy images and X-ray diffraction patterns classified 15 different porous carbon electrodes into slit-shape and worm-like-shape, and the pore size distributions of the carbons were carefully determined applying the grand canonical Monte Carlo method to N2 adsorption isotherms at 77 K. The ratio of pores where solvated ions and/or desolvated ions can penetrate also has a significant effect on the EDL capacitance as well as the pore shape. The detailed study on the effect of porous morphologies on the EDLC performance indicates that a hierarchical porous structure with a worm-like shaped surface and a pore size ranging from a solvated ion to a solvent molecule is an ideal electrode structure.
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Affiliation(s)
- K Urita
- Graduate School of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki, Nagasaki 852-8521, Japan
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Affiliation(s)
- Shinji Oro
- Graduate School of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521
| | - Koki Urita
- Graduate School of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521
| | - Isamu Moriguchi
- Graduate School of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521
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Nishi M, Ohkubo T, Urita K, Moriguchi I, Kuroda Y. Experimental Information on the Adsorbed Phase of Water Formed in the Inner Pore of Single-Walled Carbon Nanotube Itself. Langmuir 2016; 32:1058-64. [PMID: 26756541 DOI: 10.1021/acs.langmuir.5b04222] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Thus far, nobody has successfully obtained the accurate information on the properties of the adsorbed phases of gases or vapors formed inside a cylindrical micropore of single-walled carbon nanotube (SWCNT) itself based on the experimental procedure. In this work, we succeeded in analyzing experimentally the properties of adsorbed nitrogen and water confined in the inner pore of SWCNT itself by opening the pore composed of close-ended SWCNT without any changes in the surface state and also by applying the unique method for characterization; both the amounts, as well as properties, of surface functional groups and the bundle structure are the same even after the treatments for introducing an open-ended structure to a close-ended one. As a result, the average pore sizes, as well as characteristic adsorption behavior, on the two types of sample were available from the analysis of respective difference adsorption isotherms of nitrogen measured at 77 K between the adsorbed amounts on the open-ended SWCNT and that on the close-ended one. The evaluated pore sizes well coincide with the results estimated by Raman data. These results strongly support that we could analyze the adsorbed phases formed only in the inner pore of SWCNTs by applying the present method. Furthermore, we could analyze the adsorbed phase of water formed inside the cylindrical micropore of SWCNTs, showing the difference in the densities of adsorbed water depending on the pore sizes from the value of bulk water; the densities of the adsorbed water were evaluated to be 0.62 and 0.71 g mL(-1) for SWCNTs having average pore sizes of 1.3 and 1.7 nm, respectively, which were in harmony with those obtained by the theoretical calculations reported by other researchers. The proposed analysis method makes it possible to recognize the focused states of the adsorbed water formed inside the cylindrical micropore of SWCNT more precisely and correctly. The method proposed will shed light on the discussion related to the detailed nature of various adsorbed gases into SWCNT, to the detailed role of adsorbed species formed inside pore in various phenomena, and to the designing the useful materials based on the gained knowledge.
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Affiliation(s)
- Masayasu Nishi
- Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University , 3-1-1 Tsushimanaka, Kita-ku, Okayama 700-8530, Japan
| | - Takahiro Ohkubo
- Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University , 3-1-1 Tsushimanaka, Kita-ku, Okayama 700-8530, Japan
| | - Koki Urita
- Division of Chemistry and Materials Science, Graduate School of Engineering, Nagasaki University , 1-14 Bunkyomachi, Nagasaki 852-8521, Japan
| | - Isamu Moriguchi
- Division of Chemistry and Materials Science, Graduate School of Engineering, Nagasaki University , 1-14 Bunkyomachi, Nagasaki 852-8521, Japan
| | - Yasushige Kuroda
- Department of Chemistry, Graduate School of Natural Science and Technology, Okayama University , 3-1-1 Tsushimanaka, Kita-ku, Okayama 700-8530, Japan
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Tabuchi H, Urita K, Moriguchi I. Effect of Carbon Nanospace on Charge–Discharge Properties of Si and SiOx Nanoparticles-Embedded Nanoporous Carbons. BCSJ 2015. [DOI: 10.1246/bcsj.20150228] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
| | - Koki Urita
- Graduate School of Engineering, Nagasaki University
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Tabuchi H, Nakamura T, Urita K, Moriguchi I. Charge–Discharge Property of Si and SiOx Nanoparticles Produced in Regulated Carbon Nanospace. CHEM LETT 2015. [DOI: 10.1246/cl.140862] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
| | | | - Koki Urita
- Graduate School of Engineering, Nagasaki University
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Urita K, Ide N, Isobe K, Furukawa H, Moriguchi I. Enhanced electric double-layer capacitance by desolvation of lithium ions in confined nanospaces of microporous carbon. ACS Nano 2014; 8:3614-3619. [PMID: 24646017 DOI: 10.1021/nn500169k] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Carbon electrodes with specific microporous structures are strongly desired to improve the performance of electric double-layer capacitors (EDLCs). We report solvated states of Li ions in confined carbon micropores affecting specific capacitance. The average Li(+) solvation number of 1 M LiClO4/propylene carbonate (PC) electrolyte introduced into porous carbon electrodes was determined using Raman spectroscopy and (7)Li NMR. Micropores with slightly larger pore size against the solvated molecules and the narrow two-dimensional spaces decreased the solvation number, enhancing specific capacitance. Hence, specific carbon morphology may be related to high EDL capacitance, and micropore structure is important in obtaining highly capacitive EDLC materials.
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Affiliation(s)
- Koki Urita
- Graduate School of Engineering, Nagasaki University , 1-14 Bunkyo-machi, Nagasaki, Nagasaki 852-8521, Japan
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Abstract
The reversibility of SnO2–Sn conversion and Sn–Li alloying/de-alloying reactions was greatly enhanced by the confinement of SnO2 nanocrystallites in regulated carbon nanospace.
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Affiliation(s)
- Shinji Oro
- Graduate School of Engineering
- Nagasaki University
- Nagasaki 852-8521, Japan
| | - Koki Urita
- Graduate School of Engineering
- Nagasaki University
- Nagasaki 852-8521, Japan
| | - Isamu Moriguchi
- Graduate School of Engineering
- Nagasaki University
- Nagasaki 852-8521, Japan
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Nishi M, Ohkubo T, Tsurusaki K, Itadani A, Ahmmad B, Urita K, Moriguchi I, Kittaka S, Kuroda Y. Highly compressed nanosolution restricted in cylindrical carbon nanospaces. Nanoscale 2013; 5:2080-2088. [PMID: 23376949 DOI: 10.1039/c2nr33681b] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We shed light on the specific hydration structure around a zinc ion of nanosolution restricted in a cylindrical micropore of single-wall carbon nanotube (SWNT) by comparison with the structure restricted in a cylindrical mesopore of multi-wall carbon nanotube (MWNT) and that of bulk aqueous solution. The average micropore width of open-pore SWNT was 0.87 nm which is equivalent to the size of a hydrated zinc ion having 6-hydrated water molecules. We could impregnate the zinc ions into the micropore of SWNT with negligible amounts of ion-exchanged species on surface functional groups by the appropriate oxidation followed by heat treatment under an inert condition. The results of X-ray absorption fine structure (XAFS) spectra confirmed that the proportion of dissolved species in nanospaces against the total adsorbed amounts of zinc ions on the open-pore SWNT and MWNT were 44 and 61%, respectively, indicating the formation of a dehydrated structure in narrower nanospaces. The structure parameters obtained by the analysis of XAFS spectra also indicate that the dehydrated and highly compressed hydration structure can be stably formed inside the cylindrical micropore of SWNT where the structure is different from that inside the slit-shaped micropore whose pore width is less than 1 nm. Such a unique structure needs not only a narrow micropore geometry which is equivalent to the size of a hydrated ion but also the cylindrical nature of the pore.
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Affiliation(s)
- Masayasu Nishi
- Department of Chemistry, Faculty of Science, Okayama University, 3-1-1 Tsushimanaka, Okayama 700-8530, Japan
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Aono S, Tsurudo T, Urita K, Moriguchi I. Direct synthesis of novel homogeneous nanocomposites of Li2MnSiO4 and carbon as a potential Li-ion battery cathode material. Chem Commun (Camb) 2013; 49:2939-41. [DOI: 10.1039/c3cc40673c] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Kubo T, Sakamoto H, Fujimori T, Itoh T, Ohba T, Kanoh H, Martínez-Escandell M, Ramos-Fernández JM, Casco M, Rodríguez-Reinoso F, Urita K, Moriguchi I, Endo M, Kaneko K. Diffusion-barrier-free porous carbon monoliths as a new form of activated carbon. ChemSusChem 2012; 5:2271-2277. [PMID: 23019152 DOI: 10.1002/cssc.201200234] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Revised: 06/21/2012] [Indexed: 06/01/2023]
Abstract
For the practical use of activated carbon (AC) as an adsorbent of CH(4) , tightly packed monoliths with high microporosity are supposed to be one of the best morphologies in terms of storage capacity per apparent volume of the adsorbent material. However, monolith-type ACs may cause diffusion obstacles in adsorption processes owing to their necked pore structures among the densely packed particles, which result in a lower adsorption performance than that of the corresponding powder ACs. To clarify the relationship between the pore structure and CH₄ adsorptivity, microscopic observations, structural studies on the nanoscale, and conductivity measurements (thermal and electrical) were performed on recently developed binder-free, self-sinterable ACs in both powder and monolithic forms. The monolith samples exhibited higher surface areas and electrical conductivities than the corresponding powder samples. Supercritical CH₄ adsorption isotherms were measured for each powder and monolith sample at up to 7 MPa at 263, 273, and 303 K to elucidate their isosteric heats of adsorption and adsorption rate constants, which revealed that the morphologies of the monolith samples did not cause serious drawbacks for the adsorption and desorption processes. This will further facilitate the availability of diffusion-barrier-free microporous carbon monoliths as practical CH₄ storage adsorbents.
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Affiliation(s)
- Takashi Kubo
- Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan
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Aono S, Urita K, Yamada H, Moriguchi I. Rapid Synthesis and Charge–Discharge Properties of LiMnPO4 Nanocrystallite-embedded Porous Carbons. CHEM LETT 2012. [DOI: 10.1246/cl.2012.162] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
| | - Koki Urita
- Graduate School of Engineering, Nagasaki University
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Urita K, Shiga Y, Fujimori T, Iiyama T, Hattori Y, Kanoh H, Ohba T, Tanaka H, Yudasaka M, Iijima S, Moriguchi I, Okino F, Endo M, Kaneko K. Confinement in Carbon Nanospace-Induced Production of KI Nanocrystals of High-Pressure Phase. J Am Chem Soc 2011; 133:10344-7. [DOI: 10.1021/ja202565r] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Koki Urita
- Department of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
| | - Yuichi Shiga
- Graduate School of Science, Chiba University, 1-33 Inage-ku, Yayoi-cho, Chiba 263-8522, Japan
| | - Toshihiko Fujimori
- Research Center for Exotic Nanocarbons (JST), Shinshu University, 4-17-1 Wakasato, Nagano 380-8553 Japan
| | - Taku Iiyama
- Department of Chemistry, Faculty of Science, Shinshu University, 3-1-1, Asahi, Matsumoto, Nagano 390-8621, Japan
| | - Yoshiyuki Hattori
- Faculty of Textile Science and Technology, Shinshu University, 3-15-1 Tuneda, Ueda 386-8567, Japan
| | - Hirofumi Kanoh
- Graduate School of Science, Chiba University, 1-33 Inage-ku, Yayoi-cho, Chiba 263-8522, Japan
| | - Tomonori Ohba
- Graduate School of Science, Chiba University, 1-33 Inage-ku, Yayoi-cho, Chiba 263-8522, Japan
| | - Hideki Tanaka
- Department of Chemical Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan
| | - Masako Yudasaka
- National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 205-8565, Japan
| | - Sumio Iijima
- National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 205-8565, Japan
| | - Isamu Moriguchi
- Department of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki 852-8521, Japan
| | - Fujio Okino
- Faculty of Textile Science and Technology, Shinshu University, 3-15-1 Tuneda, Ueda 386-8567, Japan
| | - Morinobu Endo
- Research Center for Exotic Nanocarbons (JST), Shinshu University, 4-17-1 Wakasato, Nagano 380-8553 Japan
| | - Katsumi Kaneko
- Graduate School of Science, Chiba University, 1-33 Inage-ku, Yayoi-cho, Chiba 263-8522, Japan
- Research Center for Exotic Nanocarbons (JST), Shinshu University, 4-17-1 Wakasato, Nagano 380-8553 Japan
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Hashimoto S, Fujimori T, Tanaka H, Urita K, Ohba T, Kanoh H, Itoh T, Asai M, Sakamoto H, Niimura S, Endo M, Rodriguez-Reinoso F, Kaneko K. Anomaly of CH4 Molecular Assembly Confined in Single-Wall Carbon Nanohorn Spaces. J Am Chem Soc 2011; 133:2022-4. [DOI: 10.1021/ja1086886] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Sachie Hashimoto
- Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan
| | - Toshihiko Fujimori
- Research Center for Exotic Nanocarbons (JST), Shinshu University, 4-17-1 Wakasato, Nagano-city, Nagano 380-8553, Japan
| | - Hideki Tanaka
- Department of Chemical Engineering, Graduate School of Engineering, Kyoto University, Nishikyo, Kyoto 615-8510, Japan
| | - Koki Urita
- Department of Applied Chemistry, Faculty of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki-shi, Nagasaki 852-8521, Japan
| | - Tomonori Ohba
- Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan
| | - Hirofumi Kanoh
- Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan
| | - Tsutomu Itoh
- Research Center for Exotic Nanocarbons (JST), Shinshu University, 4-17-1 Wakasato, Nagano-city, Nagano 380-8553, Japan
| | - Michihiro Asai
- Research Center for Exotic Nanocarbons (JST), Shinshu University, 4-17-1 Wakasato, Nagano-city, Nagano 380-8553, Japan
| | - Hirotoshi Sakamoto
- Research Center for Exotic Nanocarbons (JST), Shinshu University, 4-17-1 Wakasato, Nagano-city, Nagano 380-8553, Japan
| | - Subaru Niimura
- Research Center for Exotic Nanocarbons (JST), Shinshu University, 4-17-1 Wakasato, Nagano-city, Nagano 380-8553, Japan
| | - Morinobu Endo
- Research Center for Exotic Nanocarbons (JST), Shinshu University, 4-17-1 Wakasato, Nagano-city, Nagano 380-8553, Japan
| | | | - Katsumi Kaneko
- Research Center for Exotic Nanocarbons (JST), Shinshu University, 4-17-1 Wakasato, Nagano-city, Nagano 380-8553, Japan
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Affiliation(s)
- Peter Branton
- Group Research & Development, British American Tobacco, Regents Park Road, Millbrook, Southampton SO15 8TL, U.K
| | - Koki Urita
- Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba-shi 263-8522, Japan
| | - Katsumi Kaneko
- Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba-shi 263-8522, Japan
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Noguchi D, Tanaka H, Fujimori T, Kagita H, Hattori Y, Honda H, Urita K, Utsumi S, Wang ZM, Ohba T, Kanoh H, Hata K, Kaneko K. Selective D2 adsorption enhanced by the quantum sieving effect on entangled single-wall carbon nanotubes. J Phys Condens Matter 2010; 22:334207. [PMID: 21386497 DOI: 10.1088/0953-8984/22/33/334207] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The quantum sieving effect of D(2) over H(2) is examined at 40 and 77 K by means of experiments and GCMC simulations, for two types of single-wall carbon nanotubes that are distinguishable by their unique entangled structures; (1) a well-bundled SWCNT and (2) loosely-assembled SWCNT produced by the super growth method (SG-SWCNT). Oxidized SWCNT samples of which the so-called internal sites are accessible for H(2) and D(2), are also studied. Experimental H(2) and D(2) adsorption properties on the well-bundled SWCNTs are compared with the simulated ones, revealing that pore-blocking and restricted diffusion of the molecules suppress the high selectivity of D(2) over H(2). The non-oxidized SG-SWCNT assembly shows the highest selectivity among the SWCNT samples, both at 40 and 77 K. The high selectivity of the SG-SWCNT assembly, which is pronounced even at 77 K, is ascribed to their unique assembly structure.
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Affiliation(s)
- Daisuke Noguchi
- Department of Chemistry Graduate School of Science, Chiba University, 1-33 Yayoi, Inage, Chiba 263-8522, Japan
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Fujimori T, Urita K, Ohba T, Kanoh H, Kaneko K. Evidence of Dynamic Pentagon−Heptagon Pairs in Single-Wall Carbon Nanotubes using Surface-Enhanced Raman Scattering. J Am Chem Soc 2010; 132:6764-7. [DOI: 10.1021/ja100760m] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Toshihiko Fujimori
- Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi, Inage, Chiba 263-8522, Japan, and Department of Applied Chemistry, Faculty of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki-shi, Nagasaki 852-8521, Japan
| | - Koki Urita
- Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi, Inage, Chiba 263-8522, Japan, and Department of Applied Chemistry, Faculty of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki-shi, Nagasaki 852-8521, Japan
| | - Tomonori Ohba
- Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi, Inage, Chiba 263-8522, Japan, and Department of Applied Chemistry, Faculty of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki-shi, Nagasaki 852-8521, Japan
| | - Hirofumi Kanoh
- Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi, Inage, Chiba 263-8522, Japan, and Department of Applied Chemistry, Faculty of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki-shi, Nagasaki 852-8521, Japan
| | - Katsumi Kaneko
- Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi, Inage, Chiba 263-8522, Japan, and Department of Applied Chemistry, Faculty of Engineering, Nagasaki University, 1-14 Bunkyo-machi, Nagasaki-shi, Nagasaki 852-8521, Japan
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Tanaka A, Iiyama T, Ohba T, Ozeki S, Urita K, Fujimori T, Kanoh H, Kaneko K. Effect of a Quaternary Ammonium Salt on Propylene Carbonate Structure in Slit-Shape Carbon Nanopores. J Am Chem Soc 2010; 132:2112-3. [DOI: 10.1021/ja9087874] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Akimi Tanaka
- Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan, and Department of Chemistry, Faculty of Science, Shinshu University, 3-1-1, Asahi, Matsumoto, Nagano 390-8621, Japan
| | - Taku Iiyama
- Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan, and Department of Chemistry, Faculty of Science, Shinshu University, 3-1-1, Asahi, Matsumoto, Nagano 390-8621, Japan
| | - Tomonori Ohba
- Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan, and Department of Chemistry, Faculty of Science, Shinshu University, 3-1-1, Asahi, Matsumoto, Nagano 390-8621, Japan
| | - Sumio Ozeki
- Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan, and Department of Chemistry, Faculty of Science, Shinshu University, 3-1-1, Asahi, Matsumoto, Nagano 390-8621, Japan
| | - Koki Urita
- Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan, and Department of Chemistry, Faculty of Science, Shinshu University, 3-1-1, Asahi, Matsumoto, Nagano 390-8621, Japan
| | - Toshihiko Fujimori
- Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan, and Department of Chemistry, Faculty of Science, Shinshu University, 3-1-1, Asahi, Matsumoto, Nagano 390-8621, Japan
| | - Hirofumi Kanoh
- Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan, and Department of Chemistry, Faculty of Science, Shinshu University, 3-1-1, Asahi, Matsumoto, Nagano 390-8621, Japan
| | - Katsumi Kaneko
- Department of Chemistry, Graduate School of Science, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan, and Department of Chemistry, Faculty of Science, Shinshu University, 3-1-1, Asahi, Matsumoto, Nagano 390-8621, Japan
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Arai M, Utsumi S, Kanamaru M, Urita K, Fujimori T, Yoshizawa N, Noguchi D, Nishiyama K, Hattori Y, Okino F, Ohba T, Tanaka H, Kanoh H, Kaneko K. Enhanced hydrogen adsorptivity of single-wall carbon nanotube bundles by one-step c60-pillaring method. Nano Lett 2009; 9:3694-3698. [PMID: 19842696 DOI: 10.1021/nl9015733] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Single-wall carbon nanotube (SWCNT) bundles were pillared by fullerene (C60) by the cosonication of C60 and SWCNT in toluene to utilize the interstitial pores for hydrogen storage. C60-pillared SWCNTs were confirmed by the shift in the X-ray diffraction peak and the expanded hexagonal and distorted tetragonal bundles revealed by high-resolution transmission electron microscopy. The H2 adsorptivity of the C60-pillared SWCNT bundles was twice that of the original SWCNT bundles, indicating a design route for SWCNT hydrogen storage.
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Affiliation(s)
- Miki Arai
- Graduate School of Science, Chiba University, 1-33 Yayoi, Inage, Chiba 263-8522, Japan
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Aoki Y, Urita K, Noguchi D, Itoh T, Kanoh H, Ohba T, Yudasaka M, Iijima S, Kaneko K. Efficient production of H2 and carbon nanotube from CH4 over single wall carbon nanohorn. Chem Phys Lett 2009. [DOI: 10.1016/j.cplett.2009.10.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Cheng Y, Kondo A, Noguchi H, Kajiro H, Urita K, Ohba T, Kaneko K, Kanoh H. Reversible structural change of Cu-MOF on exposure to water and its CO2 adsorptivity. Langmuir 2009; 25:4510-3. [PMID: 19271756 DOI: 10.1021/la803818p] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
It is important to study the interaction between water molecules and a host structure for understanding the adsorption mechanism of metal-organic framework (MOF) materials. The evolution of the structure of a flexible Cu-MOF, {[Cu(bpy)(H2O)2(BF4)2](bpy)} (bpy=4,4'-bipyridine), upon dehydration and rehydration was studied by thermogravimetric analysis (TGA), infrared (IR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and water adsorption. A nearly reversible structural change was observed upon rehydration. More importantly, a unique CO2 "gate adsorption" phenomenon was observed despite the exposure of the Cu-MOF to water. This shows that the Cu-MOF has relatively good stability after exposure to water.
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Affiliation(s)
- Yan Cheng
- Graduate School of Science, Chiba University, 1-33 Yayoi, Inage, Chiba 263-8522, Japan
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Hayakawa C, Urita K, Ohba T, Kanoh H, Kaneko K. Physico-chemical properties of iodine-adsorbed single-walled carbon nanotubes. Langmuir 2009; 25:1795-1799. [PMID: 19123785 DOI: 10.1021/la803395a] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
I2 was adsorbed on single-walled carbon nanotube from ethanol solution at 303 K. The I2 adsorption isotherm was Langmuirian, giving 35 (+/-10) mg g(-1) of the saturated adsorption amount (coverage 0.06-0.09). The I2-adsorption treatment of SWCNT bundles reduced the N2 adsorption amount at 77 K by only 3%; the adsorption amount of supercritical H2 at 77 K was decreased by 30% because of the I2-adsorption treatment, indicating the blocking of interstitial pores by adsorbed I2. These adsorption results indicated the adsorption of I2 molecules in the narrow interstitial pores. The I2-adsorption treatment increases the Raman intensity coming from metallic SWCNTs, and the dc electrical conductivity increased by 15% because of the I2-adsorption treatment, strongly suggesting the presence of charge-transfer interaction between I2 and SWCNTs irrespective of small coverage by I2.
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Affiliation(s)
- Chiharu Hayakawa
- Department of Chemistry, Graduate School of Science, Chiba University, Chiba 263-8522, Japan
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Itoh T, Urita K, Bekyarova E, Arai M, Yudasaka M, Iijima S, Ohba T, Kaneko K, Kanoh H. Nanoporosities and catalytic activities of Pd-tailored single wall carbon nanohorns. J Colloid Interface Sci 2008; 322:209-14. [DOI: 10.1016/j.jcis.2008.02.049] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2007] [Revised: 02/14/2008] [Accepted: 02/25/2008] [Indexed: 10/22/2022]
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Suenaga K, Wakabayashi H, Koshino M, Sato Y, Urita K, Iijima S. Imaging active topological defects in carbon nanotubes. Nat Nanotechnol 2007; 2:358-360. [PMID: 18654307 DOI: 10.1038/nnano.2007.141] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2007] [Revised: 04/11/2007] [Accepted: 04/17/2007] [Indexed: 05/26/2023]
Abstract
A single-walled carbon nanotube (SWNT) is a wrapped single graphene layer, and its plastic deformation should require active topological defects--non-hexagonal carbon rings that can migrate along the nanotube wall. Although in situ transmission electron microscopy (TEM) has been used to examine the deformation of SWNTs, these studies deal only with diameter changes and no atomistic mechanism has been elucidated experimentally. Theory predicts that some topological defects can form through the Stone-Wales transformation in SWNTs under tension at 2,000 K, and could act as a dislocation core. We demonstrate here, by means of high-resolution (HR)-TEM with atomic sensitivity, the first direct imaging of pentagon-heptagon pair defects found in an SWNT that was heated at 2,273 K. Moreover, our in situ HR-TEM observation reveals an accumulation of topological defects near the kink of a deformed nanotube. This result suggests that dislocation motions or active topological defects are indeed responsible for the plastic deformation of SWNTs.
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Urita K, Seki S, Utsumi S, Noguchi D, Kanoh H, Tanaka H, Hattori Y, Ochiai Y, Aoki N, Yudasaka M, Iijima S, Kaneko K. Effects of gas adsorption on the electrical conductivity of single-wall carbon nanohorns. Nano Lett 2006; 6:1325-8. [PMID: 16834404 DOI: 10.1021/nl060120q] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
We present significant electrical conductivity responses of the pelletized as-prepared and oxidized (ox-) single-wall carbon nanohorns (SWNHs) on adsorption of CO(2) and O(2). The morphological and pore structures of both pelletized SWNHs were examined by transmission electron microscopy (TEM) and nitrogen adsorption isotherm, leading to explicit evidences of the formation of nanoscale windows on the wall by oxidation. The SWNH and ox-SWNH induced a semiconducting behavior, strongly responded to CO(2) and O(2) adsorptions, and each exhibited n-type- and p-type-like conductivities. The electrical conductivity increase and decrease for CO(2) and O(2) adsorption, respectively, were observed for SWNH, whereas ox-SWNH showed a marked electrical conductivity drop on CO(2) adsorption and almost no change on O(2) adsorption. The dramatically different electrical conductivity response of ox-SWNH is presumed to be ascribed to the annihilation of pentagons in the single graphene wall by oxidation.
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Affiliation(s)
- Koki Urita
- Graduate School of Science and Technology, Chiba University, Japan
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Yumura T, Sato Y, Suenaga K, Urita K, Iijima S. Gate effect of vacancy-type defect of fullerene cages on metal-atom migrations in metallofullerenes. Nano Lett 2006; 6:1389-95. [PMID: 16834417 DOI: 10.1021/nl060354+] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Metal-atom migration outside from a defective fullerene cage of a metallofullerene Gd@C(82) (Ca@C(82)), where the Gd(3+) (Ca(2+)) ion is incorporated inside the C(2)(v)()-C(82) cage, is discussed in detail at the B3LYP DFT level of theory. The metal-atom migrations are initiated by the formation of vacancy-type defects involving two coordinatively unsaturated C atoms. This step, which is assumed to proceed due to energy-particle irradiation, leads to the formation of antibonding orbitals between the two C atoms. Since the antibonding orbitals can interact with vacant d-orbitals of the Gd(3)(+)() ion in an in-phase fashion, the attractive interactions allow the Gd ion to insert into the two C atoms in the defect. As a result, the metal ion passes through the defect under energy-particle irradiation. In contrast, the Ca(2+) ion with the vacant s-orbitals does not have such orbital interactions, and thus, a C-C bond is reformed between the two C atoms, which prohibits the Ca ion from penetrating the defected C(82) cage. DFT calculations nicely demonstrate that the orbital interactions control metal-atom migration around the defect site using their orbital symmetries, and therefore, the vacancy-type defect acts as a "gate" that permits a specific atom to go out from a defected fullerene cage.
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Affiliation(s)
- Takashi Yumura
- Research Center for Advanced Carbon Materials, National Institute of Advanced Industrial Science and Technology (AIST) Tsukuba, Japan.
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Utsumi S, Urita K, Kanoh H, Yudasaka M, Suenaga K, Iijima S, Kaneko K. Preparing a Magnetically Responsive Single-Wall Carbon Nanohorn Colloid by Anchoring Magnetite Nanoparticles. J Phys Chem B 2006; 110:7165-70. [PMID: 16599481 DOI: 10.1021/jp0569640] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A single-wall carbon nanohorn (SWNH) colloid was made to be magnetically responsive by anchoring magnetite nanoparticles prepared by the homogeneous mixing of FeCl(2)-FeCl(3) and NaOH solutions. Transmission electron microscopy observation showed the high dispersion of magnetite particles of 2-9 nm on the surface of the SWNH colloid, coinciding with the broad X-ray diffraction peaks of the magnetites. The magnetization measurements showed that the magnetite nanoparticles-anchored SWNH (mag-SWNH) colloid has the hybrid property of ferrimagnetism and superparamagnetism. It was demonstrated that mag-SWNH colloid dispersed in water by sonication responded to an external magnetic field, gathering toward a magnet. N(2) adsorption experiments showed the high nanoporosity of mag-SWNHs and that magnetite nanoparticles were preferably anchored at "nanowindow" sites and the entrance sites of interstitial pores. This magnetically responsive SWNH colloid should contribute to the field of drug delivery.
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Affiliation(s)
- Shigenori Utsumi
- Department of Chemistry, Faculty of Science, Chiba University, 1-33 Yayoi, Inage, Chiba 263-8522, Japan
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Urita K, Suenaga K, Sugai T, Shinohara H, Iijima S. In situ observation of thermal relaxation of interstitial-vacancy pair defects in a graphite gap. Phys Rev Lett 2005; 94:155502. [PMID: 15904158 DOI: 10.1103/physrevlett.94.155502] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2004] [Indexed: 05/02/2023]
Abstract
Direct observation of individual defects during formation and annihilation in the interlayer gap of double-wall carbon nanotubes (DWNT) is demonstrated by high-resolution transmission electron microscopy. The interlayer defects that bridge two adjacent graphen layers in DWNT are stable for a macroscopic time at the temperature below 450 K. These defects are assigned to a cluster of one or two interstitial-vacancy pairs (I-V pairs) and often disappear just after their formation at higher temperatures due to an instantaneous recombination of the interstitial atom with vacancy. Systematic observations performed at the elevated temperatures find a threshold for the defect annihilation at 450-500 K, which, indeed, corresponds to the known temperature for the Wigner energy release.
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Affiliation(s)
- Koki Urita
- Research Center for Advanced Carbon Materials, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, 305-8565, Japan
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Hashimoto A, Suenaga K, Urita K, Shimada T, Sugai T, Bandow S, Shinohara H, Iijima S. Atomic correlation between adjacent graphene layers in double-wall carbon nanotubes. Phys Rev Lett 2005; 94:045504. [PMID: 15783570 DOI: 10.1103/physrevlett.94.045504] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2004] [Indexed: 05/24/2023]
Abstract
Atomic correlation between adjacent graphene layers was elucidated for double-wall carbon nanotubes (DWNTs) through a chiral index assignment of two nested nanotubes by high-resolution transmission electron microscopy. Our analysis provides a rather constant diameter difference close to 0.75 nm but no chiral angle correlation between the constituent nanotubes in the concentric DWNTs. The local atomic correlation as a commensurate graphene stacking was repeatedly found in eccentric DWNTs and circumscribed nanotubes, which should lead to elastic deformation and bundling of nanotubes.
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Affiliation(s)
- Ayako Hashimoto
- Research Center for Advanced Carbon Materials, National Institute of Advanced Industrial Science and Technology, Tsukuba, 305-8565, Japan.
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Hashimoto A, Suenaga K, Gloter A, Urita K, Iijima S. Direct evidence for atomic defects in graphene layers. Nature 2004; 430:870-3. [PMID: 15318216 DOI: 10.1038/nature02817] [Citation(s) in RCA: 568] [Impact Index Per Article: 28.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2004] [Accepted: 07/06/2004] [Indexed: 11/09/2022]
Abstract
Atomic-scale defects in graphene layers alter the physical and chemical properties of carbon nanostructures. Theoretical predictions have recently shown that energetic particles such as electrons and ions can induce polymorphic atomic defects in graphene layers as a result of knock-on atom displacements. However, the number of experimental reports on these defects is limited. The graphite network in single-walled carbon nanotubes has been visualized by transmission electron microscopy (TEM) and their chiral indices have been determined. But the methods used require a long image acquisition time and intensive numerical treatments after observations to find an 'average' image, which prevents the accurate detection and investigation of defect structures. Here we report observations in situ of defect formation in single graphene layers by high-resolution TEM. The observed structures are expected to be of use when engineering the properties of carbon nanostructures for specific device applications.
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Affiliation(s)
- Ayako Hashimoto
- Research Center for Advanced Carbon Materials, National Institute for Advanced Industrial Science and Technology (AIST), Tsukuba, 305-8565, Japan
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