1
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Sakurai S, Yamada M, He J, Hata K, Futaba DN. A Hydrogen-Free Approach for Activating an Fe Catalyst Using Trace Amounts of Noble Metals and Confinement into Nanoparticles. J Phys Chem Lett 2022; 13:1879-1885. [PMID: 35175057 DOI: 10.1021/acs.jpclett.2c00144] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Metallic iron (Fe) represents an exceptionally active catalyst, as shown in its use in the Haber-Bosch process to dissociate nitrogen molecules; however, the ease of corrosion by oxidation limits its usage. Hence, in most applications using metallic Fe catalysts, hydrogen is a necessary reactant. We report a novel hydrogen-free approach to fabricating reduced, highly active, and corrosion-resistive Fe-based catalysts using trace levels of noble metals (NMs) such as Ir, Rh, and Pt confined in the nanoparticle (NP). X-ray photoelectron spectroscopy (XPS) revealed that as little as ∼0.3 atom % was sufficient to induce the reduction of Fe. Extensive XPS analysis showed that the reduced NM atoms segregated to the NP surface and reduced the surrounding Fe atoms. We demonstrated the catalytic activity of the nanoparticles by the efficient synthesis of submillimeter tall, vertically aligned, and mainly double-walled carbon nanotube arrays using a completely hydrogen-free chemical vapor deposition process.
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Affiliation(s)
- Shunsuke Sakurai
- CNT-Application Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
| | - Maho Yamada
- CNT-Application Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
| | - Jinping He
- CNT-Application Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
| | - Kenji Hata
- CNT-Application Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
| | - Don N Futaba
- CNT-Application Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
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2
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Wang M, Nakamura K, Arifuku M, Kiyoyanagi N, Inoue T, Kobayashi Y. Growth of Single-Walled Carbon Nanotubes from Solid Carbon Nanoparticle Seeds via Cap Formation Engineering with a Two-Step Growth Process and Water Vapor Supply. ACS OMEGA 2022; 7:3639-3648. [PMID: 35128272 PMCID: PMC8811922 DOI: 10.1021/acsomega.1c06268] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Accepted: 01/11/2022] [Indexed: 06/14/2023]
Abstract
Solid carbon nanoparticles are promising growth seeds to prepare single-walled carbon nanotubes (SWCNTs) at high temperatures, at which the SWCNT crystallinity should be improved significantly but conventional metal catalyst nanoparticles are unstable and suffer from aggregation. The noncatalytic nature of solid carbon nanoparticles, however, makes SWCNT growth inefficient, resulting in a limited growth yield. In this study, we develop a two-step chemical vapor deposition process to efficiently synthesize high-crystallinity SWCNTs at high temperatures from solid carbon nanoparticles obtained from nanodiamond. Based on thermodynamic considerations, the growth conditions are separately adjusted to supply different growth driving forces which are suitable for the formation of the initial cap structures and for the stationary elongation of SWCNTs. This process, called cap formation engineering, improves the nucleation density of the cap structures. We examined the changes in crystallinity, amorphous carbon deposition, diameter, and yield of SWCNTs with respect to the synthesis conditions. By controlling the initial growth conditions, high-quality SWCNTs are grown with improved yield. With the addition of water vapor as the etchant, deposition of amorphous carbon at high temperatures was further prevented. The results provide a pathway for precise growth control of SWCNTs from unconventional solid growth seeds.
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Affiliation(s)
- Mengyue Wang
- Department
of Applied Physics, Osaka University, Suita, Osaka 565-0871, Japan
| | - Keisuke Nakamura
- Department
of Applied Physics, Osaka University, Suita, Osaka 565-0871, Japan
| | - Michiharu Arifuku
- Nippon
Kayaku Co., Ltd., 31-12, Shimo 3-chome, Kita-ku, Tokyo 115-8588, Japan
| | - Noriko Kiyoyanagi
- Nippon
Kayaku Co., Ltd., 31-12, Shimo 3-chome, Kita-ku, Tokyo 115-8588, Japan
| | - Taiki Inoue
- Department
of Applied Physics, Osaka University, Suita, Osaka 565-0871, Japan
| | - Yoshihiro Kobayashi
- Department
of Applied Physics, Osaka University, Suita, Osaka 565-0871, Japan
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3
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Radman H, Baniadam M, Maghrebi M, Hamed Mosavian MT, Eshraghi MJ. Quality and Quantity of Carbon Nanotube Arrays Grown in Different Pressures and Temperatures Across Absorption-, Surface-, and Diffusion-Controlled Regimes. Ind Eng Chem Res 2020. [DOI: 10.1021/acs.iecr.0c01242] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Hassan Radman
- Department of Chemical Engineering, Ferdowsi University of Mashhad, Mashhad, Khorasan Razavi, IR 9177948944, Iran
| | - Majid Baniadam
- Department of Chemical Engineering, Ferdowsi University of Mashhad, Mashhad, Khorasan Razavi, IR 9177948944, Iran
| | - Morteza Maghrebi
- Department of Chemical Engineering, Ferdowsi University of Mashhad, Khorasan Razavi, IR 917751111, Iran
| | | | - Mohamad Javad Eshraghi
- Department of Semiconductors, Material & Energy Research Center, Meshkin dasht, Alborz, IR 477714155, Iran
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4
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Tlili I, Alkanhal TA, Barzinjy AA, Dara RN, Shafee A, Li Z. Investigation of thermal characteristics of carbon nanotubes: Measurement and dependence. J Mol Liq 2019. [DOI: 10.1016/j.molliq.2019.111564] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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5
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Lee YS, Lee SY, Kim KS, Noda S, Shim SE, Yang CM. Effective Heat Transfer Pathways of Thermally Conductive Networks Formed by One-Dimensional Carbon Materials with Different Sizes. Polymers (Basel) 2019; 11:polym11101661. [PMID: 31614671 PMCID: PMC6835844 DOI: 10.3390/polym11101661] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 10/02/2019] [Accepted: 10/08/2019] [Indexed: 11/16/2022] Open
Abstract
We investigated the heat transfer behavior of thermally conductive networks with one-dimensional carbon materials to design effective heat transfer pathways for hybrid filler systems of polymer matrix composites. Nano-sized few-walled carbon nanotubes (FWCNTs) and micro-sized mesophase pitch-based carbon fibers (MPCFs) were used as the thermally conductive materials. The bulk density and thermal conductivity of the FWCNT films increased proportionally with the ultrasonication time due to the enhanced dispersibility of the FWCNTs in an ethanol solvent. The ultrasonication-induced densification of the FWCNT films led to the effective formation of filler-to-filler connections, resulting in improved thermal conductivity. The thermal conductivity of the FWCNT-MPCF hybrid films was proportional to the MPCF content (maximum thermal conductivity at an MPCF content of 60 wt %), indicating the synergistic effect on the thermal conductivity enhancement. Moreover, the MPCF-to-MPCF heat transfer pathways in the FWCNT-MPCF hybrid films were the most effective in achieving high thermal conductivity due to the smaller interfacial area and shorter heat transfer pathway of the MPCFs. The FWCNTs could act as thermal bridges between neighboring MPCFs for effective heat transfer. Furthermore, the incorporation of Ag nanoparticles of approximately 300 nm into the FWCNT-MPCF hybrid film dramatically enhanced the thermal conductivity, which was closely related to a decreased thermal interfacial resistance at the intersection points between the materials. Epoxy-based composites loaded with the FWCNTs, MPCFs, FWCNT-MPCF hybrids, and FWCNT-MPCF-Ag hybrid fillers were also fabricated. A similar trend in thermal conductivity was observed in the polymer matrix composite with carbon-based hybrid films.
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Affiliation(s)
- Yun Seon Lee
- Institute of Advanced Composite Materials, Korea Institute of Science and Technology (KIST), 92 Chudong-ro, Wanju-gun, Jeonbuk 55324, Korea.
- Department of Chemical Engineering, Inha University, 100 Inha-ro, Nam-gu, Incheon 22212, Korea.
| | - Seung-Yong Lee
- Institute of Advanced Composite Materials, Korea Institute of Science and Technology (KIST), 92 Chudong-ro, Wanju-gun, Jeonbuk 55324, Korea.
- Magok R&D campus, LG Innotek, 30 Magokjungang 10-ro, Gangseo-gu, Seoul 07796, Korea.
| | - Keun Soo Kim
- Department of Physics and Graphene Research Institute, Sejong University, 209 Neungdong-ro, Gwangjin-gu, Seoul 05006, Korea.
| | - Suguru Noda
- Department of Applied Chemistry, School of Advanced Science and Engineering, Waseda University, 3-4-1 Okubo, Shinjuku-ku, Tokyo 169-8555, Japan.
| | - Sang Eun Shim
- Department of Chemical Engineering, Inha University, 100 Inha-ro, Nam-gu, Incheon 22212, Korea.
| | - Cheol-Min Yang
- Institute of Advanced Composite Materials, Korea Institute of Science and Technology (KIST), 92 Chudong-ro, Wanju-gun, Jeonbuk 55324, Korea.
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6
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Rao R, Pint CL, Islam AE, Weatherup RS, Hofmann S, Meshot ER, Wu F, Zhou C, Dee N, Amama PB, Carpena-Nuñez J, Shi W, Plata DL, Penev ES, Yakobson BI, Balbuena PB, Bichara C, Futaba DN, Noda S, Shin H, Kim KS, Simard B, Mirri F, Pasquali M, Fornasiero F, Kauppinen EI, Arnold M, Cola BA, Nikolaev P, Arepalli S, Cheng HM, Zakharov DN, Stach EA, Zhang J, Wei F, Terrones M, Geohegan DB, Maruyama B, Maruyama S, Li Y, Adams WW, Hart AJ. Carbon Nanotubes and Related Nanomaterials: Critical Advances and Challenges for Synthesis toward Mainstream Commercial Applications. ACS NANO 2018; 12:11756-11784. [PMID: 30516055 DOI: 10.1021/acsnano.8b06511] [Citation(s) in RCA: 168] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Advances in the synthesis and scalable manufacturing of single-walled carbon nanotubes (SWCNTs) remain critical to realizing many important commercial applications. Here we review recent breakthroughs in the synthesis of SWCNTs and highlight key ongoing research areas and challenges. A few key applications that capitalize on the properties of SWCNTs are also reviewed with respect to the recent synthesis breakthroughs and ways in which synthesis science can enable advances in these applications. While the primary focus of this review is on the science framework of SWCNT growth, we draw connections to mechanisms underlying the synthesis of other 1D and 2D materials such as boron nitride nanotubes and graphene.
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Affiliation(s)
- Rahul Rao
- Materials and Manufacturing Directorate, Air Force Research Laboratory , Wright Patterson Air Force Base , Dayton , Ohio 45433 , United States
- UES Inc. , Dayton , Ohio 45433 , United States
| | - Cary L Pint
- Department of Mechanical Engineering , Vanderbilt University , Nashville , Tennessee 37235 United States
| | - Ahmad E Islam
- Materials and Manufacturing Directorate, Air Force Research Laboratory , Wright Patterson Air Force Base , Dayton , Ohio 45433 , United States
- UES Inc. , Dayton , Ohio 45433 , United States
| | - Robert S Weatherup
- School of Chemistry , University of Manchester , Oxford Road , Manchester M13 9PL , U.K
- University of Manchester at Harwell, Diamond Light Source, Didcot , Oxfordshire OX11 0DE , U.K
| | - Stephan Hofmann
- Department of Engineering , University of Cambridge , Cambridge CB3 0FA , U.K
| | - Eric R Meshot
- Physical and Life Sciences Directorate , Lawrence Livermore National Laboratory , Livermore , California 94550 United States
| | - Fanqi Wu
- Ming-Hsieh Department of Electrical Engineering , University of Southern California , Los Angeles , California 90089 , United States
| | - Chongwu Zhou
- Ming-Hsieh Department of Electrical Engineering , University of Southern California , Los Angeles , California 90089 , United States
| | - Nicholas Dee
- Department of Mechanical Engineering , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
| | - Placidus B Amama
- Tim Taylor Department of Chemical Engineering , Kansas State University , Manhattan , Kansas 66506 , United States
| | - Jennifer Carpena-Nuñez
- Materials and Manufacturing Directorate, Air Force Research Laboratory , Wright Patterson Air Force Base , Dayton , Ohio 45433 , United States
- UES Inc. , Dayton , Ohio 45433 , United States
| | - Wenbo Shi
- Department of Chemical and Environmental Engineering , Yale University , New Haven , Connecticut 06520 , United States
| | - Desiree L Plata
- Department of Civil and Environmental Engineering , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
| | - Evgeni S Penev
- Department of Materials Science and NanoEngineering , Rice University , Houston , Texas 77005 , United States
| | - Boris I Yakobson
- Department of Materials Science and NanoEngineering , Rice University , Houston , Texas 77005 , United States
| | - Perla B Balbuena
- Department of Chemical Engineering, Department of Materials Science and Engineering, Department of Chemistry , Texas A&M University , College Station , Texas 77843 , United States
| | - Christophe Bichara
- Aix-Marseille University and CNRS , CINaM UMR 7325 , 13288 Marseille , France
| | - Don N Futaba
- Nanotube Research Center , National Institute of Advanced Industrial Science and Technology (AIST) , Tsukuba 305-8565 , Japan
| | - Suguru Noda
- Department of Applied Chemistry and Waseda Research Institute for Science and Engineering , Waseda University , 3-4-1 Okubo , Shinjuku-ku, Tokyo 169-8555 , Japan
| | - Homin Shin
- Security and Disruptive Technologies Research Centre, Emerging Technologies Division , National Research Council Canada , Ottawa , Ontario K1A 0R6 , Canada
| | - Keun Su Kim
- Security and Disruptive Technologies Research Centre, Emerging Technologies Division , National Research Council Canada , Ottawa , Ontario K1A 0R6 , Canada
| | - Benoit Simard
- Security and Disruptive Technologies Research Centre, Emerging Technologies Division , National Research Council Canada , Ottawa , Ontario K1A 0R6 , Canada
| | - Francesca Mirri
- Department of Materials Science and NanoEngineering , Rice University , Houston , Texas 77005 , United States
| | - Matteo Pasquali
- Department of Materials Science and NanoEngineering , Rice University , Houston , Texas 77005 , United States
| | - Francesco Fornasiero
- Physical and Life Sciences Directorate , Lawrence Livermore National Laboratory , Livermore , California 94550 United States
| | - Esko I Kauppinen
- Department of Applied Physics , Aalto University School of Science , P.O. Box 15100 , FI-00076 Espoo , Finland
| | - Michael Arnold
- Department of Materials Science and Engineering University of Wisconsin-Madison , Madison , Wisconsin 53706 , United States
| | - Baratunde A Cola
- George W. Woodruff School of Mechanical Engineering and School of Materials Science and Engineering , Georgia Institute of Technology , Atlanta , Georgia 30332 , United States
| | - Pavel Nikolaev
- Materials and Manufacturing Directorate, Air Force Research Laboratory , Wright Patterson Air Force Base , Dayton , Ohio 45433 , United States
- UES Inc. , Dayton , Ohio 45433 , United States
| | - Sivaram Arepalli
- Department of Materials Science and NanoEngineering , Rice University , Houston , Texas 77005 , United States
| | - Hui-Ming Cheng
- Tsinghua-Berkeley Shenzhen Institute , Tsinghua University , Shenzhen 518055 , China
- Shenyang National Laboratory for Materials Science , Institute of Metal Research, Chinese Academy of Sciences , Shenyang 110016 , China
| | - Dmitri N Zakharov
- Center for Functional Nanomaterials , Brookhaven National Laboratory , Upton , New York 11973 , United States
| | - Eric A Stach
- Department of Materials Science and Engineering , University of Pennsylvania , Philadelphia , Pennsylvania 19104 , United States
| | - Jin Zhang
- College of Chemistry and Molecular Engineering , Peking University , Beijing 100871 , China
| | - Fei Wei
- Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology, Department of Chemical Engineering , Tsinghua University , Beijing 100084 , China
| | - Mauricio Terrones
- Department of Physics and Center for Two-Dimensional and Layered Materials , The Pennsylvania State University , University Park , Pennsylvania 16802 , United States
| | - David B Geohegan
- Center for Nanophase Materials Sciences , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
| | - Benji Maruyama
- Materials and Manufacturing Directorate, Air Force Research Laboratory , Wright Patterson Air Force Base , Dayton , Ohio 45433 , United States
| | - Shigeo Maruyama
- Department of Mechanical Engineering , The University of Tokyo , 7-3-1 Hongo , Bunkyo-ku , Tokyo 113-8656 , Japan
| | - Yan Li
- College of Chemistry and Molecular Engineering , Peking University , Beijing 100871 , China
| | - W Wade Adams
- Department of Materials Science and NanoEngineering , Rice University , Houston , Texas 77005 , United States
| | - A John Hart
- Department of Mechanical Engineering , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
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7
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Otsuka K, Yamamoto S, Inoue T, Koyano B, Ukai H, Yoshikawa R, Xiang R, Chiashi S, Maruyama S. Digital Isotope Coding to Trace the Growth Process of Individual Single-Walled Carbon Nanotubes. ACS NANO 2018; 12:3994-4001. [PMID: 29613761 DOI: 10.1021/acsnano.8b01630] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Single-walled carbon nanotubes (SWCNTs) are attracting increasing attention as an ideal material for high-performance electronics through the preparation of arrays of purely semiconducting SWCNTs. Despite significant progress in the controlled synthesis of SWCNTs, their growth mechanism remains unclear due to difficulties in analyzing the time-resolved growth of individual SWCNTs under practical growth conditions. Here we present a method for tracing the diverse growth profiles of individual SWCNTs by embedding digitally coded isotope labels. Raman mapping showed that, after various incubation times, SWCNTs elongated monotonically until their abrupt termination. Ex situ analysis offered an opportunity to capture rare chirality changes along the SWCNTs, which resulted in sudden acceleration/deceleration of the growth rate. Dependence on growth parameters, such as temperature and carbon concentration, was also traced along individual SWCNTs, which could provide clues to chirality control. Systematic growth studies with a variety of catalysts and conditions, which combine the presented method with other characterization techniques, will lead to further understanding and control of chirality, length, and density of SWCNTs.
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Affiliation(s)
- Keigo Otsuka
- Department of Mechanical Engineering , The University of Tokyo , 7-3-1 Hongo , Bunkyo-ku , Tokyo 113-8656 , Japan
| | - Shun Yamamoto
- Department of Mechanical Engineering , The University of Tokyo , 7-3-1 Hongo , Bunkyo-ku , Tokyo 113-8656 , Japan
| | - Taiki Inoue
- Department of Mechanical Engineering , The University of Tokyo , 7-3-1 Hongo , Bunkyo-ku , Tokyo 113-8656 , Japan
| | - Bunsho Koyano
- Department of Mechanical Engineering , The University of Tokyo , 7-3-1 Hongo , Bunkyo-ku , Tokyo 113-8656 , Japan
| | - Hiroyuki Ukai
- Department of Mechanical Engineering , The University of Tokyo , 7-3-1 Hongo , Bunkyo-ku , Tokyo 113-8656 , Japan
| | - Ryo Yoshikawa
- Department of Mechanical Engineering , The University of Tokyo , 7-3-1 Hongo , Bunkyo-ku , Tokyo 113-8656 , Japan
| | - Rong Xiang
- Department of Mechanical Engineering , The University of Tokyo , 7-3-1 Hongo , Bunkyo-ku , Tokyo 113-8656 , Japan
| | - Shohei Chiashi
- Department of Mechanical Engineering , The University of Tokyo , 7-3-1 Hongo , Bunkyo-ku , Tokyo 113-8656 , Japan
| | - Shigeo Maruyama
- Department of Mechanical Engineering , The University of Tokyo , 7-3-1 Hongo , Bunkyo-ku , Tokyo 113-8656 , Japan
- Energy NanoEngineering Laboratory , National Institute of Advanced Industrial Science and Technology (AIST) , 1-2-1 Namiki , Tsukuba 305-8564 , Japan
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8
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Matsumoto N, Oshima A, Ishizawa S, Chen G, Hata K, Futaba D. One millimeter per minute growth rates for single wall carbon nanotube forests enabled by porous metal substrates. RSC Adv 2018; 8:7810-7817. [PMID: 35539099 PMCID: PMC9078519 DOI: 10.1039/c7ra13093g] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 02/13/2018] [Indexed: 11/21/2022] Open
Abstract
We report an exceptionally high-efficiency synthesis of long single-wall carbon nanotube (SWCNT) forests using porous substrates (metal meshes) in place of nonporous flat substrates. This study examined the dependence of the growth efficiency on various mesh structures, including wire diameter, aperture size, and total surface area. We demonstrated that the synthesis of SWCNT forests is highly dependent on the initial porosity as well as maintaining the open pores throughout the duration of the growth. Our results show that carbon nanotubes (CNTs) can be grown on all surfaces of the mesh in high efficiency with the optimum growth efficiency observed for a mesh porosity of ∼30%. Based on these results, we demonstrated the high efficiency synthesis of SWCNT forests (height: >3.47 mm, average growth rate: 301 μm min−1, and yield: 12.7 mg cm−2 in 10 min growth time). Furthermore, we showed that the initial growth rates exceeded 1 millimeter per minute (1000 μm min−1). Our results further indicate that metal meshes represent a viable alternative to nonporous flat substrates for the efficient synthesis of tall and high yielding SWCNTs. We report an exceptionally high-efficiency synthesis of long single-wall carbon nanotube (SWCNT) forests using a porous substrate (metal meshes) in place of nonporous flat substrates.![]()
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Affiliation(s)
- Naoyuki Matsumoto
- National Institute of Advanced Industrial Science and Technology (AIST)
- Tsukuba
- Japan
| | - Azusa Oshima
- National Institute of Advanced Industrial Science and Technology (AIST)
- Tsukuba
- Japan
| | - Sachiko Ishizawa
- National Institute of Advanced Industrial Science and Technology (AIST)
- Tsukuba
- Japan
| | - Guohai Chen
- National Institute of Advanced Industrial Science and Technology (AIST)
- Tsukuba
- Japan
| | - Kenji Hata
- National Institute of Advanced Industrial Science and Technology (AIST)
- Tsukuba
- Japan
| | - Don N. Futaba
- National Institute of Advanced Industrial Science and Technology (AIST)
- Tsukuba
- Japan
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9
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Schneider JJ. Vertically Aligned Carbon Nanotubes as Platform for Biomimetically Inspired Mechanical Sensing, Bioactive Surfaces, and Electrical Cell Interfacing. ACTA ACUST UNITED AC 2017; 1:e1700101. [PMID: 32646166 DOI: 10.1002/adbi.201700101] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Revised: 07/04/2017] [Indexed: 12/30/2022]
Abstract
Vertically aligned carbon nanotubes (VACNTs) are one dimensional carbon objects anchored atop of a solid substrate. They are geometrically fixed in contrast to their counterparts, randomly oriented carbon nanotubes (CNTs). In this progress report, the breadth in which these one dimensional, mechanically flexible, though robust and electrical conducting carbon nanostructures can be employed as functional material is shown and our research is put in perspective to work in the last five to ten years. The connection between the different areas touched in this report is the biomimetic-materials approach, which rely on the hairy morphology of VACNTs. These properties in connection with their electrical conductivity offer possibilities towards new functional features and applications of VACNTs. To appreciate the possibilities of biomimetic research with VACNTs, first their material characteristics are given to make the reader familiar with specific features of their synthesis, the peculiarities in arranging and controlling the morphology of CNTs in a vertical alignment as well as a current understanding of these properties on a microscopic basis. In doing so, similarities as well as differences, which offer new possibilities for biomimetic studies of VACNTS with respect to multiwalled randomly oriented CNTs, will become clear.
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Affiliation(s)
- Jörg J Schneider
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Alarich-Weiss Str. 12, 64287, Darmstadt, Germany
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10
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Shi W, Li J, Polsen ES, Oliver CR, Zhao Y, Meshot ER, Barclay M, Fairbrother DH, Hart AJ, Plata DL. Oxygen-promoted catalyst sintering influences number density, alignment, and wall number of vertically aligned carbon nanotubes. NANOSCALE 2017; 9:5222-5233. [PMID: 28397885 DOI: 10.1039/c6nr09802a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A lack of synthetic control and reproducibility during vertically aligned carbon nanotube (CNT) synthesis has stifled many promising applications of organic nanomaterials. Oxygen-containing species are particularly precarious in that they have both beneficial and deleterious effects and are notoriously difficult to control. Here, we demonstrated diatomic oxygen's ability, independent of water, to tune oxide-supported catalyst thin film dewetting and influence nanoscale (diameter and wall number) and macro-scale (alignment and density) properties for as-grown vertically aligned CNTs. In particular, single- or few-walled CNT forests were achieved at very low oxygen loading, with single-to-multi-walled CNT diameters ranging from 4.8 ± 1.3 nm to 6.4 ± 1.1 nm over 0-800 ppm O2, and an expected variation in alignment, where both were related to the annealed catalyst morphology. Morphological differences were not the result of subsurface diffusion, but instead occurred via Ostwald ripening under several hundred ppm O2, and this effect was mitigated by high H2 concentrations and not due to water vapor (as confirmed in O2-free water addition experiments), supporting the importance of O2 specifically. Further characterization of the interface between the Fe catalyst and Al2O3 support revealed that either oxygen-deficit metal oxide or oxygen-adsorption on metals could be functional mechanisms for the observed catalyst nanoparticle evolution. Taken as a whole, our results suggest that the impacts of O2 and H2 on the catalyst evolution have been underappreciated and underleveraged in CNT synthesis, and these could present a route toward facile manipulation of CNT forest morphology through control of the reactive gaseous atmosphere alone.
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Affiliation(s)
- Wenbo Shi
- Department of Chemical and Environmental Engineering, Yale University, New Haven, CT, USA.
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11
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Vengrenovich RD, Ivanskii BV, Panko II, Kryvetskii VI. Ostwald's ripening of single-layer carbon nanotubes. APPLIED OPTICS 2016; 55:B4-B10. [PMID: 27140129 DOI: 10.1364/ao.55.0000b4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2015] [Accepted: 11/24/2015] [Indexed: 06/05/2023]
Abstract
Analysis of experimentally obtained size distribution functions in the form of percentage of carbon nanotubes (CNTs) versus their diameters shows increasing intermediate tube diameters with increasing concentration of the source of carbon atoms. In this paper, the mechanism of growth is associated with Ostwald's ripening CNTs, which are considered massive cylindrical nanoclusters of various diameter and height embedded in a solution (volume or surface) of carbon atoms. Interaction of nanoclusters is realized through the Gibbs-Thomson effect, resulting in increasing their average diameters. Validity of the proposed mechanism of increasing average diameters of nanotubes is proved by comparison of the experimentally obtained histograms with theoretically computed dependences. We use the generalized Lifshitz-Slyozov-Wagner and the Chakraverty-Wagner distributions, both computed via assumption that growth of nanoclusters (nanotubes) is controlled simultaneously by (volume or surface) diffusion and by speed of chemical connections' formation or by chemical reaction (Wagner's mechanism of growth). Under specified technological parameters and conditions of synthesis, the obtained theoretically distributions fit well with the experimental histograms for single-layer CNTs.
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12
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Amama PB, Islam AE, Saber SM, Huffman DR, Maruyama B. Understanding properties of engineered catalyst supports using contact angle measurements and X-ray reflectivity. NANOSCALE 2016; 8:2927-2936. [PMID: 26781333 DOI: 10.1039/c5nr08108d] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
There is significant interest in broadening the type of catalyst substrates that support the growth of high-quality carbon nanotube (CNT) carpets. In this study, ion beam bombardment has been utilized to modify catalyst substrates for CNT carpet growth. Using a combination of contact angle measurements (CAMs) and X-ray reflectivity (XRR) for the first time, new correlations between the physicochemical properties of pristine and engineered catalyst substrates and CNT growth behavior have been established. The engineered surfaces obtained after exposure to different degrees of ion beam damage have distinct physicochemical properties (porosity, layer thickness, and acid-base properties). The CAM data were analyzed using the van Oss-Chaudhury-Good model, enabling the determination of the acid-base properties of the substrate surfaces. For the XRR data, a Fourier analysis of the interference patterns enabled extraction of layer thickness, while the atomic density and interfacial roughness were extracted by analyzing the amplitude of the interference oscillations. The dramatic transformation of the substrate from "inactive" to "active" is attributed to a combined effect of substrate porosity or damage depth and Lewis basicity. The results reveal that the efficiency of catalyst substrates can be further improved by increasing the substrate basicity, if the minimum surface porosity is established. This study advances the use of a non-thermochemical approach for catalyst substrate engineering, as well as demonstrates the combined utility of CAM and XRR as a powerful, nondestructive, and reliable tool for rational catalyst design.
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Affiliation(s)
- Placidus B Amama
- Department of Chemical Engineering, Kansas State University, Manhattan, Kansas 66506, USA.
| | - Ahmad E Islam
- Air Force Research Laboratory, Materials and Manufacturing Directorate, RXAS, Wright-Patterson AFB, Ohio 45433, USA and National Research Council, National Academy of Sciences, Washington D.C. 20001, USA
| | - Sammy M Saber
- Air Force Research Laboratory, Materials and Manufacturing Directorate, RXAS, Wright-Patterson AFB, Ohio 45433, USA and UES Inc., Dayton, Ohio 45432, USA
| | - Daniel R Huffman
- Air Force Research Laboratory, Materials and Manufacturing Directorate, RXAS, Wright-Patterson AFB, Ohio 45433, USA and UES Inc., Dayton, Ohio 45432, USA
| | - Benji Maruyama
- Air Force Research Laboratory, Materials and Manufacturing Directorate, RXAS, Wright-Patterson AFB, Ohio 45433, USA
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13
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Chen G, Davis RC, Futaba DN, Sakurai S, Kobashi K, Yumura M, Hata K. A sweet spot for highly efficient growth of vertically aligned single-walled carbon nanotube forests enabling their unique structures and properties. NANOSCALE 2016; 8:162-171. [PMID: 26619935 DOI: 10.1039/c5nr05537g] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We investigated the correlation between growth efficiency and structural parameters of single-walled carbon nanotube (SWCNT) forests and report the existence of a SWCNT "sweet spot" in the CNT diameter and spacing domain for highly efficient synthesis. Only within this region could SWCNTs be grown efficiently. Through the investigation of the growth rates for ∼340 CNT forests spanning diameters from 1.3 to 8.0 nm and average spacing from 5 to 80 nm, this "sweet spot" was found to exist because highly efficient growth was constrained by several mechanistic boundaries that either hindered the formation or reduced the growth rate of SWCNT forests. Specifically, with increased diameter SWCNTs transitioned to multiwalled CNTs (multiwall border), small diameter SWCNTs could only be grown at low growth rates (low efficiency border), sparse SWCNTs lacked the requirements to vertically align (lateral growth border), and high density catalysts could not be prepared (high catalyst density border). As a result, the SWCNTs synthesized within this "sweet spot" possessed a unique set of characteristics vital for the development applications, such as large diameter, long, aligned, defective, and high specific surface area.
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Affiliation(s)
- Guohai Chen
- Technology Research Association for Single Wall Carbon Nanotubes (TASC), Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan and National Institute of Advanced Industrial Science and Technology (AIST), Central 5, 1-1-1- Higashi, Tsukuba, Ibaraki 305-8565, Japan.
| | - Robert C Davis
- Department of Physics and Astronomy, Brigham Young University, Provo, Utah 84602, USA
| | - Don N Futaba
- Technology Research Association for Single Wall Carbon Nanotubes (TASC), Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan and National Institute of Advanced Industrial Science and Technology (AIST), Central 5, 1-1-1- Higashi, Tsukuba, Ibaraki 305-8565, Japan.
| | - Shunsuke Sakurai
- Technology Research Association for Single Wall Carbon Nanotubes (TASC), Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan and National Institute of Advanced Industrial Science and Technology (AIST), Central 5, 1-1-1- Higashi, Tsukuba, Ibaraki 305-8565, Japan.
| | - Kazufumi Kobashi
- Technology Research Association for Single Wall Carbon Nanotubes (TASC), Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan and National Institute of Advanced Industrial Science and Technology (AIST), Central 5, 1-1-1- Higashi, Tsukuba, Ibaraki 305-8565, Japan.
| | - Motoo Yumura
- Technology Research Association for Single Wall Carbon Nanotubes (TASC), Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan and National Institute of Advanced Industrial Science and Technology (AIST), Central 5, 1-1-1- Higashi, Tsukuba, Ibaraki 305-8565, Japan.
| | - Kenji Hata
- Technology Research Association for Single Wall Carbon Nanotubes (TASC), Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan and National Institute of Advanced Industrial Science and Technology (AIST), Central 5, 1-1-1- Higashi, Tsukuba, Ibaraki 305-8565, Japan.
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14
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The Application of Gas Dwell Time Control for Rapid Single Wall Carbon Nanotube Forest Synthesis to Acetylene Feedstock. NANOMATERIALS 2015; 5:1200-1210. [PMID: 28347060 PMCID: PMC5304639 DOI: 10.3390/nano5031200] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Revised: 07/13/2015] [Accepted: 07/14/2015] [Indexed: 11/28/2022]
Abstract
One aspect of carbon nanotube (CNT) synthesis that remains an obstacle to realize industrial mass production is the growth efficiency. Many approaches have been reported to improve the efficiency, either by lengthening the catalyst lifetime or by increasing the growth rate. We investigated the applicability of dwell time and carbon flux control to optimize yield, growth rate, and catalyst lifetime of water-assisted chemical vapor deposition of single-walled carbon nanotube (SWCNT) forests using acetylene as a carbon feedstock. Our results show that although acetylene is a precursor to CNT synthesis and possesses a high reactivity, the SWCNT forest growth efficiency is highly sensitive to dwell time and carbon flux similar to ethylene. Through a systematic study spanning a wide range of dwell time and carbon flux levels, the relationship of the height, growth rate, and catalyst lifetime is found. Further, for the optimum conditions for 10 min growth, SWCNT forests with ~2500 μm height, ~350 μm/min initial growth rates and extended lifetimes could be achieved by increasing the dwell time to ~5 s, demonstrating the generality of dwell time control to highly reactive gases.
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15
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Wang H, Na C. Chemical Bath Deposition of Aluminum Oxide Buffer on Curved Surfaces for Growing Aligned Carbon Nanotube Arrays. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:7401-7409. [PMID: 26053766 DOI: 10.1021/acs.langmuir.5b01002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Direct growth of vertically aligned carbon nanotube (CNT) arrays on substrates requires the deposition of an aluminum oxide buffer (AOB) layer to prevent the diffusion and coalescence of catalyst nanoparticles. Although AOB layers can be readily created on flat substrates using a variety of physical and chemical methods, the preparation of AOB layers on substrates with highly curved surfaces remains challenging. Here, we report a new solution-based method for preparing uniform layers of AOB on highly curved surfaces by the chemical bath deposition of basic aluminum sulfate and annealing. We show that the thickness of AOB layer can be increased by extending the immersion time of a substrate in the chemical bath, following the classical Johnson-Mehl-Avrami-Kolmogorov crystallization kinetics. The increase of AOB thickness in turn leads to the increase of CNT length and the reduction of CNT curviness. Using this method, we have successfully synthesized dense aligned CNT arrays of micrometers in length on substrates with highly curved surfaces including glass fibers, stainless steel mesh, and porous ceramic foam.
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Affiliation(s)
- Haitao Wang
- †Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, 156 Fitzpatrick Hall, Notre Dame, Indiana 46556, United States
| | - Chongzheng Na
- †Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, 156 Fitzpatrick Hall, Notre Dame, Indiana 46556, United States
- ‡Department of Civil, Environmental, and Construction Engineering, Texas Tech University, 10th Street and Akron Avenue, Lubbock, Texas 79409, United States
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16
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Chen G, Davis RC, Kimura H, Sakurai S, Yumura M, Futaba DN, Hata K. The relationship between the growth rate and the lifetime in carbon nanotube synthesis. NANOSCALE 2015; 7:8873-8. [PMID: 25913386 DOI: 10.1039/c5nr01125f] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
We report an inverse relationship between the carbon nanotube (CNT) growth rate and the catalyst lifetime by investigating the dependence of growth kinetics for ∼330 CNT forests on the carbon feedstock, carbon concentration, and growth temperature. We found that the increased growth temperature led to increased CNT growth rate and shortened catalyst lifetime for all carbon feedstocks, following an inverse relationship of a fairly constant maximum height. For the increased carbon concentration, the carbon feedstocks fell into two groups where ethylene/butane showed an increased/decreased growth rate and a decreased/increased lifetime indicating different rate-limiting growth processes. In addition, this inverse relationship held true for different types of CNTs synthesized by various chemical vapor deposition techniques and continuously spanned a 1000-times range in both the growth rate and catalyst lifetime, indicating the generality and fundamental nature of this behavior originating from the growth mechanism of CNTs itself. These results suggest that it would be fundamentally difficult to achieve a fast growth with a long lifetime.
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Affiliation(s)
- Guohai Chen
- Technology Research Association for Single Wall Carbon Nanotubes (TASC), Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
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17
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Wyss RM, Klare JE, Park HG, Noy A, Bakajin O, Lulevich V. Water-assisted growth of uniform 100 mm diameter SWCNT arrays. ACS APPLIED MATERIALS & INTERFACES 2014; 6:21019-21025. [PMID: 25408997 DOI: 10.1021/am505692a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We report a simple method for growing high-quality single-walled carbon nanotube (SWCNT) arrays on 100 mm wafers via the addition of water vapor to highly purified gases during the CNT growth step. We show that adding a small amount of water during growth helps to create a uniform catalyst distribution and yields high-quality (Raman G/D of 26 ± 3), high-density (up to 6 × 10(11) cm(-2)) and uniform SWCNT arrays on 100 mm large wafers. We rationalize our finding by suggesting that the addition of water decreases catalyst mobility, preventing its coarsening at higher temperatures. We also report a new mechanism of catalyst inactivation in wafer-scale growth using ultrapurified gas sources by the formation of large, 5 ± 3 μm iron particles. We found such formations to be common for substrates with large temperature gradients, such as for wafers processed in a typical cold-wall chemical vapor deposition reactor.
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Affiliation(s)
- Roman M Wyss
- Nanoscience for Energy Technology and Sustainability, Department of Mechanical and Process Engineering, ETH Zurich , Sonneggstrasse 3, Zürich CH-8092, Switzerland
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18
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Di J, Wang X, Xing Y, Zhang Y, Zhang X, Lu W, Li Q, Zhu YT. Dry-processable carbon nanotubes for functional devices and composites. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2014; 10:4606-25. [PMID: 25123967 DOI: 10.1002/smll.201401465] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2014] [Revised: 07/01/2014] [Indexed: 05/23/2023]
Abstract
Assembly of carbon nanotubes (CNTs) in effective and productive ways is of vital importance to their application. Recent progress in synthesis of CNTs has inspired new strategies for utilizing the unique physiochemical properties of CNTs in macroscale materials and devices. Assembling CNTs by dry processes (e.g., directly collecting CNTs in the form of freestanding films followed by pressing, stretching, and multilayer stacking instead of dispersing them in solution) not only considerably simplifies the processes but also avoids structural damage to the CNTs. Various dry-processable CNTs are reviewed, focusing on their synthesis, properties, and applications. The synthesis techniques are organized in terms of aggregative morphologies and microstructure control of CNTs. Important applications such as functional thin-film devices, strong CNT films, and composites are included. The opportunities and challenges in the synthesis techniques and fabrication of advanced composites and devices are discussed.
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Affiliation(s)
- Jiangtao Di
- Suzhou Institute of Nano-tech and Nano-bionics, Chinese Academy of Sciences, Suzhou, 215123, China
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19
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Islam AE, Nikolaev P, Amama PB, Saber S, Zakharov D, Huffman D, Erford M, Sargent G, Semiatin SL, Stach EA, Maruyama B. Engineering the activity and lifetime of heterogeneous catalysts for carbon nanotube growth via substrate ion beam bombardment. NANO LETTERS 2014; 14:4997-5003. [PMID: 25079258 DOI: 10.1021/nl501417h] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We demonstrate that argon ion bombardment of single crystal sapphire leads to the creation of substrates that support the growth of vertically aligned carbon nanotubes from iron catalysts with a density, height, and quality equivalent to those grown on conventional, disordered alumina supports. We quantify the evolution of the catalyst using a range of surface characterization techniques and demonstrate the ability to engineer and pattern the catalyst support through control of ion beam bombardment parameters.
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Affiliation(s)
- A E Islam
- Materials and Manufacturing Directorate, Air Force Research Laboratory, Wright-Patterson Air Force Base , Dayton, Ohio 45433, United States
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20
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Pilgrim GA, Leadbetter JW, Qiu F, Siitonen AJ, Pilgrim SM, Krauss TD. Electron conductive and proton permeable vertically aligned carbon nanotube membranes. NANO LETTERS 2014; 14:1728-1733. [PMID: 24564862 DOI: 10.1021/nl403696y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We report the fabrication of membranes hundreds of micrometers thick that demonstrate efficient electron conduction and proton transport through vertically aligned arrays of multiwalled carbon nanotubes (NTs) impregnated by epoxy. Electrical transport was Ohmic with a conductivity of 495 mS cm(-1). Protons traversed the membrane through the NT bore with a current of 5.84 × 10(-6) A. Good electron and proton transport, chemical robustness, and simple fabrication suggest NT membranes have potential in artificial photosynthesis applications.
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Affiliation(s)
- Gregory A Pilgrim
- Department of Chemistry and ‡The Institute of Optics, University of Rochester , Rochester, New York 14620, United States
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21
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Sakurai S, Kamada F, Futaba DN, Yumura M, Hata K. Influence of lengths of millimeter-scale single-walled carbon nanotube on electrical and mechanical properties of buckypaper. NANOSCALE RESEARCH LETTERS 2013; 8:546. [PMID: 24373328 PMCID: PMC3884011 DOI: 10.1186/1556-276x-8-546] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Accepted: 12/16/2013] [Indexed: 06/03/2023]
Abstract
The electrical conductivity and mechanical strength of carbon nanotube (CNT) buckypaper comprised of millimeter-scale long single-walled CNT (SWCNT) was markedly improved by the use of longer SWCNTs. A series of buckypapers, fabricated from SWCNT forests of varying heights (350, 700, 1,500 μm), showed that both the electrical conductivity (19 to 45 S/cm) and tensile strength (27 to 52 MPa) doubled. These improvements were due to improved transfer of electron and load through a reduced number of junctions for longer SWCNTs. Interestingly, no effects of forest height on the thermal diffusivity of SWCNT buckypapers were observed. Further, these findings provide evidence that the actual SWCNT length in forests is similar to the height.
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Affiliation(s)
- Shunsuke Sakurai
- Technology Research Association for Single Wall Carbon Nanotubes (TASC), Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
- National Institute of Advanced Industrial Science and Technology (AIST), Central 5, 1-1-1, Higashi, Tsukuba, Ibaraki 305-8565, Japan
| | - Fuminori Kamada
- Technology Research Association for Single Wall Carbon Nanotubes (TASC), Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
| | - Don N Futaba
- Technology Research Association for Single Wall Carbon Nanotubes (TASC), Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
- National Institute of Advanced Industrial Science and Technology (AIST), Central 5, 1-1-1, Higashi, Tsukuba, Ibaraki 305-8565, Japan
| | - Motoo Yumura
- Technology Research Association for Single Wall Carbon Nanotubes (TASC), Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
- National Institute of Advanced Industrial Science and Technology (AIST), Central 5, 1-1-1, Higashi, Tsukuba, Ibaraki 305-8565, Japan
| | - Kenji Hata
- Technology Research Association for Single Wall Carbon Nanotubes (TASC), Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
- National Institute of Advanced Industrial Science and Technology (AIST), Central 5, 1-1-1, Higashi, Tsukuba, Ibaraki 305-8565, Japan
- Japan Science and Technology Agency (JST), Honcho 4-1-8, Kawaguchi 332-0012, Japan
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22
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Sakurai S, Inaguma M, Futaba DN, Yumura M, Hata K. Diameter and density control of single-walled carbon nanotube forests by modulating Ostwald ripening through decoupling the catalyst formation and growth processes. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2013; 9:3584-3592. [PMID: 23625816 DOI: 10.1002/smll.201300223] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Indexed: 06/02/2023]
Abstract
A continuous and wide range control of the diameter (1.9-3.2 nm) and density (0.03-0.11 g cm(-3) ) of single-walled carbon nanotube (SWNT) forests is demonstrated by decoupling the catalyst formation and SWNT growth processes. Specifically, by managing the catalyst formation temperature and H2 exposure, the redistribution of the Fe catalyst thin film into nanoparticles is controlled while a fixed growth condition preserved the growth yield. The diameter and density are inversely correlated, where low/high density forests would consist of large/small diameter SWNTs, which is proposed as a general rule for the structural control of SWNT forests. The catalyst formation process is modeled by considering the competing processes, Ostwald ripening, and subsurface diffusion, where the dominant mechanism is found to be Ostwald ripening. Specifically, H2 exposure increases catalyst surface energy and decreases diameter, while increased temperature leads to increased diffusion on the surface and an increase in diameter.
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Affiliation(s)
- Shunsuke Sakurai
- Nanotube Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Central 5, 1-1-1, Higashi, Tsukuba, Ibaraki, 305-8565, Japan; Technology Research Association for Single Wall Carbon Nanotubes (TASC), Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki, 305-8565, Japan
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23
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Chen Z, Kim DY, Hasegawa K, Noda S. Methane-assisted chemical vapor deposition yielding millimeter-tall single-wall carbon nanotubes of smaller diameter. ACS NANO 2013; 7:6719-6728. [PMID: 23844982 DOI: 10.1021/nn401556t] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We examined the use of low purity H2 (96 vol % H2 with 4 vol % CH4) in chemical vapor deposition (CVD) using a C2H2 feedstock, and obtained vertically aligned single-wall carbon nanotubes (VA-SWCNTs) with unexpectedly smaller diameters, larger height, and higher quality compared with those grown using pure H2. During the catalyst annealing, carbon deposited at a small amount from CH4 on the Fe particles, which kept them small and dense. During CVD, CH4 prevented the Fe particles from coarsening, resulting in an enhanced growth lifetime and suppressed diameter increase of growing SWCNTs. These effects were observed only for CH4, and not for C2H4 or C2H2. CH4-assisted CVD is an efficient and practical method that uses H2 containing CH4 that is available as a byproduct in chemical factories.
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Affiliation(s)
- Zhongming Chen
- Department of Chemical System Engineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
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24
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Rakov EG. Materials made of carbon nanotubes. The carbon nanotube forest. RUSSIAN CHEMICAL REVIEWS 2013. [DOI: 10.1070/rc2013v082n06abeh004340] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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A Fundamental Limitation of Small Diameter Single-Walled Carbon Nanotube Synthesis-A Scaling Rule of the Carbon Nanotube Yield with Catalyst Volume. MATERIALS 2013; 6:2633-2641. [PMID: 28811399 PMCID: PMC5521222 DOI: 10.3390/ma6072633] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Revised: 06/18/2013] [Accepted: 06/24/2013] [Indexed: 11/25/2022]
Abstract
Understanding the fundamental mechanisms and limiting processes of the growth of single-walled carbon nanotube (SWCNT) would serve as a guide to achieve further control on structural parameters of SWCNT. In this paper, we have studied the growth kinetics of a series of SWCNT forests continuously spanning a wide range of diameters (1.9–3.2 nm), and have revealed an additional fundamental growth limiting process where the mass of the individual SWCNT is determined by the individual catalyst volume. Calculation of the conversion rate of carbon atoms into CNTs per Fe atom is 2 × 102 atoms per second. This rate limiting process provides an important understanding where the larger diameter SWCNT would grow faster, and thus be more suited for mass production.
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26
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Kimura H, Goto J, Yasuda S, Sakurai S, Yumura M, Futaba DN, Hata K. Unexpectedly high yield carbon nanotube synthesis from low-activity carbon feedstocks at high concentrations. ACS NANO 2013; 7:3150-3157. [PMID: 23458321 DOI: 10.1021/nn305513e] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We report a new direction for highly efficient carbon nanotube (CNT) synthesis where, in place of conventional highly reactive carbon feedstocks at low concentrations, highly stable carbon feedstocks at high concentrations were shown to produce superior yields. We found that a saturated hydrocarbon that is considered to possess a low reactivity, delivered at high concentrations, could achieve an extremely high growth yield (2.5 times that when using ethylene). This result stems from the unique behavior where the CNT yield linearly increased with carbon concentration, in contrast to more reactive carbon feedstocks, where the yield peaks. We propose that the mechanisms for the growth kinetics for high- and low-reactivity carbon feedstocks are fundamentally different, where the latter benefits from a longer catalyst lifetime because of a relatively low production rate of carbon impurities.
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Affiliation(s)
- Hiroe Kimura
- Nanotube Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, 305-8565, Japan
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27
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Bedewy M, Hart AJ. Mechanical coupling limits the density and quality of self-organized carbon nanotube growth. NANOSCALE 2013; 5:2928-2937. [PMID: 23455411 DOI: 10.1039/c3nr34067h] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Aligned carbon nanotube (CNT) structures are promising for many applications; however, as-grown CNT "forests" synthesized by chemical vapor deposition (CVD) are typically low-density and mostly comprise tortuous defective CNTs. Here, we present evidence that the density and alignment of self-organized CNT growth is limited by mechanical coupling among CNTs in contact, in combination with their diameter-dependent growth rates. This study is enabled by comprehensive X-ray characterization of the spatially and temporally-varying internal morphology of CNT forests. Based on this data, we model the time evolution and diameter-dependent scaling of the ensuing mechanical forces on catalyst nanoparticles during CNT growth, which arise from the mismatch between the collective lengthening rate of the forest and the diameter-dependent growth rates of individual CNTs. In addition to enabling self-organization of CNTs into forests, time-varying forces between CNTs in contact dictate the hierarchical tortuous morphology of CNT forests, and may be sufficient to influence the structural quality of CNTs. These forces reach a maximum that is coincident with the maximum density observed in our growth process, and are proportional to CNT diameter. Therefore, we propose that improved manufacturing strategies for self-organized CNTs should consider both chemical and mechanical effects. This may be especially necessary to achieve high density CNT forests with low defect density, such as for improved thermal interfaces and high-permeability membranes.
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Affiliation(s)
- Mostafa Bedewy
- Mechanosynthesis Group, Department of Mechanical Engineering, University of Michigan, 2350 Hayward Street, Ann Arbor, MI 48109, USA
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28
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Youn SK, Yazdani N, Patscheider J, Park HG. Facile diameter control of vertically aligned, narrow single-walled carbon nanotubes. RSC Adv 2013. [DOI: 10.1039/c2ra22392a] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
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29
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Xiang R, Einarsson E, Murakami Y, Shiomi J, Chiashi S, Tang Z, Maruyama S. Diameter modulation of vertically aligned single-walled carbon nanotubes. ACS NANO 2012; 6:7472-9. [PMID: 22812723 DOI: 10.1021/nn302750x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
We demonstrate wide-range diameter modulation of vertically aligned single-walled carbon nanotubes (SWNTs) using a wet chemistry prepared catalyst. In order to ensure compatibility to electronic applications, the current minimum mean diameter of 2 nm for vertically aligned SWNTs is challenged. The mean diameter is decreased to about 1.4 nm by reducing Co catalyst concentrations to 1/100 or by increasing Mo catalyst concentrations by five times. We also propose a novel spectral analysis method that allows one to distinguish absorbance contributions from the upper, middle, and lower parts of a nanotube array. We use this method to quantitatively characterize the slight diameter change observed along the array height. On the basis of further investigation of the array and catalyst particles, we conclude that catalyst aggregation-rather than Ostwald ripening-dominates the growth of metal particles.
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Affiliation(s)
- Rong Xiang
- State Key Laboratory of Optoelectronic Materials and Technologies, School of Physics and Engineering, Sun Yat-Sen University, Guangzhou 510275, China.
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Meshot ER, Verploegen E, Bedewy M, Tawfick S, Woll AR, Green KS, Hromalik M, Koerner LJ, Philipp HT, Tate MW, Gruner SM, Hart AJ. High-speed in situ X-ray scattering of carbon nanotube film nucleation and self-organization. ACS NANO 2012; 6:5091-5101. [PMID: 22571676 DOI: 10.1021/nn300758f] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The production of high-performance carbon nanotube (CNT) materials demands understanding of the growth behavior of individual CNTs as well as collective effects among CNTs. We demonstrate the first use of grazing incidence small-angle X-ray scattering to monitor in real time the synthesis of CNT films by chemical vapor deposition. We use a custom-built cold-wall reactor along with a high-speed pixel array detector resulting in a time resolution of 10 msec. Quantitative models applied to time-resolved X-ray scattering patterns reveal that the Fe catalyst film first rapidly dewets into well-defined hemispherical particles during heating in a reducing atmosphere, and then the particles coarsen slowly upon continued annealing. After introduction of the carbon source, the initial CNT diameter distribution closely matches that of the catalyst particles. However, significant changes in CNT diameter can occur quickly during the subsequent CNT self-organization process. Correlation of time-resolved orientation data to X-ray scattering intensity and height kinetics suggests that the rate of self-organization is driven by both the CNT growth rate and density, and vertical CNT growth begins abruptly when CNT alignment reaches a critical threshold. The dynamics of CNT size evolution and self-organization vary according to the catalyst annealing conditions and substrate temperature. Knowledge of these intrinsically rapid processes is vital to improve control of CNT structure and to enable efficient manufacturing of high-density arrays of long, straight CNTs.
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Affiliation(s)
- Eric R Meshot
- Mechanosynthesis Group, Department of Mechanical Engineering, University of Michigan, 2350 Hayward Street, Ann Arbor, Michigan 48109, USA
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31
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Zhong G, Warner JH, Fouquet M, Robertson AW, Chen B, Robertson J. Growth of ultrahigh density single-walled carbon nanotube forests by improved catalyst design. ACS NANO 2012; 6:2893-903. [PMID: 22439978 DOI: 10.1021/nn203035x] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
We have grown vertically aligned single-walled carbon nanotube forests with an area density of 1.5 × 10(13) cm(-2), the highest yet achieved, by reducing the average diameter of the nanotubes. We use a nanolaminate Fe-Al(2)O(3) catalyst design consisting of three layers of Al(2)O(3), Fe, and Al(2)O(3), in which the lower Al(2)O(3) layer is densified by an oxygen plasma treatment to increase its diffusion barrier properties, to allow a thinner catalyst layer to be used. This high nanotube density is desirable for using carbon nanotubes as interconnects in integrated circuits.
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Affiliation(s)
- Guofang Zhong
- Department of Engineering, University of Cambridge, Cambridge CB3 0FA, United Kingdom
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32
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Han ZJ, Ostrikov K. Uniform, dense arrays of vertically aligned, large-diameter single-walled carbon nanotubes. J Am Chem Soc 2012; 134:6018-24. [PMID: 22409445 DOI: 10.1021/ja300805s] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Precisely controlled reactive chemical vapor synthesis of highly uniform, dense arrays of vertically aligned single-walled carbon nanotubes (SWCNTs) using tailored trilayered Fe/Al(2)O(3)/SiO(2) catalyst is demonstrated. More than 90% population of thick nanotubes (>3 nm in diameter) can be produced by tailoring the thickness and microstructure of the secondary catalyst supporting SiO(2) layer, which is commonly overlooked. The proposed model based on the atomic force microanalysis suggests that this tailoring leads to uniform and dense arrays of relatively large Fe catalyst nanoparticles on which the thick SWCNTs nucleate, while small nanotubes and amorphous carbon are effectively etched away. Our results resolve a persistent issue of selective (while avoiding multiwalled nanotubes and other carbon nanostructures) synthesis of thick vertically aligned SWCNTs whose easily switchable thickness-dependent electronic properties enable advanced applications in nanoelectronic, energy, drug delivery, and membrane technologies.
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Affiliation(s)
- Zhao Jun Han
- Plasma Nanoscience Centre Australia, CSIRO Materials Science and Engineering, Lindfield, New South Wales 2070, Australia
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33
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Sakurai S, Nishino H, Futaba DN, Yasuda S, Yamada T, Maigne A, Matsuo Y, Nakamura E, Yumura M, Hata K. Role of subsurface diffusion and Ostwald ripening in catalyst formation for single-walled carbon nanotube forest growth. J Am Chem Soc 2012; 134:2148-53. [PMID: 22233092 DOI: 10.1021/ja208706c] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Here we show that essentially any Fe compounds spanning Fe salts, nanoparticles, and buckyferrocene could serve as catalysts for single-walled carbon nanotube (SWNT) forest growth when supported on AlO(x) and annealed in hydrogen. This observation was explained by subsurface diffusion of Fe atoms into the AlO(x) support induced by hydrogen annealing where most of the deposited Fe left the surface and the remaining Fe atoms reconfigured into small nanoparticles suitable for SWNT growth. Interestingly, the average diameters of the SWNTs grown from all iron compounds studied were nearly identical (2.8-3.1 nm). We interpret that the offsetting effects of Ostwald ripening and subsurface diffusion resulted in the ability to grow SWNT forests with similar average diameters regardless of the initial Fe catalyst.
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Affiliation(s)
- Shunsuke Sakurai
- Nanotube Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8565, Japan
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34
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35
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Isogai S, Ohnishi R, Katayama M, Kubota J, Kim DY, Noda S, Cha D, Takanabe K, Domen K. Composite of TiN Nanoparticles and Few-Walled Carbon Nanotubes and Its Application to the Electrocatalytic Oxygen Reduction Reaction. Chem Asian J 2011; 7:286-9. [DOI: 10.1002/asia.201100715] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2011] [Indexed: 11/06/2022]
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36
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Bedewy M, Meshot ER, Reinker MJ, Hart AJ. Population growth dynamics of carbon nanotubes. ACS NANO 2011; 5:8974-8989. [PMID: 22023221 DOI: 10.1021/nn203144f] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Understanding the population growth behavior of filamentary nanostructures, such as carbon nanotubes (CNTs), is hampered by the lack of characterization techniques capable of probing statistical variations with high spatial resolution. We present a comprehensive methodology for studying the population growth dynamics of vertically aligned CNT forests, utilizing high-resolution spatial mapping of synchrotron X-ray scattering and attenuation, along with real-time height kinetics. We map the CNT alignment and dimensions within CNT forests, revealing broadening and focusing of size distributions during different stages of the process. Then, we calculate the number density and mass density of the CNT population versus time, which are true measures of the reaction kinetics. We find that the mass-based kinetics of a CNT population is accurately represented by the S-shaped Gompertz model of population growth, although the forest height and CNT length kinetics are essentially linear. Competition between catalyst activation and deactivation govern the rapid initial acceleration and slow decay of the CNT number density. The maximum CNT density (i.e., the overall catalyst activity) is limited by gas-phase reactions and catalyst-surface interactions, which collectively exhibit autocatalytic behavior. Thus, we propose a comprehensive picture of CNT population growth which combines both chemical and mechanical cooperation. Our findings are relevant to both bulk and substrate-based CNT synthesis methods and provide general insights into the self-assembly and collective growth of filamentary nanostructures.
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Affiliation(s)
- Mostafa Bedewy
- Mechanosynthesis Group, Department of Mechanical Engineering, University of Michigan, 2350 Hayward Street, Ann Arbor, Michigan 48109, USA
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37
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Geohegan DB, Puretzky AA, Jackson JJ, Rouleau CM, Eres G, More KL. Flux-dependent growth kinetics and diameter selectivity in single-wall carbon nanotube arrays. ACS NANO 2011; 5:8311-8321. [PMID: 21916517 DOI: 10.1021/nn2030397] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The nucleation and growth kinetics of single-wall carbon nanotubes in aligned arrays have been measured using fast pulses of acetylene and in situ optical diagnostics in conjunction with low pressure chemical vapor deposition (CVD). Increasing the acetylene partial pressure is shown to decrease nucleation times by three orders of magnitude, permitting aligned nanotube arrays to nucleate and grow to micrometers lengths within single gas pulses at high (up to 7 μm/s) peak growth rates and short ∼0.5 s times. Low-frequency Raman scattering (>10 cm(-1)) and transmission electron microscopy measurements show that increasing the feedstock flux in both continuous- and pulsed-CVD shifts the product distribution to large single-wall carbon nanotube diameters >2.5 nm. Sufficiently high acetylene partial pressures in pulsed-CVD appear to temporarily terminate the growth of the fastest-growing, small-diameter nanotubes by overcoating the more catalytically active, smaller catalyst nanoparticles within the ensemble with non-nanotube carbon in agreement with a growth model. The results indicate that subsets of catalyst nanoparticle ensembles nucleate, grow, and terminate growth within different flux ranges according to their catalytic activity.
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Affiliation(s)
- David B Geohegan
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory , Oak Ridge, Tennessee 37831-6488, United States.
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38
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Tessonnier JP, Su DS. Recent progress on the growth mechanism of carbon nanotubes: a review. CHEMSUSCHEM 2011; 4:824-47. [PMID: 21732543 DOI: 10.1002/cssc.201100175] [Citation(s) in RCA: 130] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2011] [Indexed: 05/14/2023]
Abstract
Tremendous progress has been achieved during the past 20 years on not only improving the yields of carbon nanotubes and move progressively towards their mass production, but also on gaining a profound fundamental understanding of the nucleation and the growth processes. Parameters that influence the yield but also the quality (e.g., microstructure, homogeneity within a batch) are better understood. The influence of the carbon precursor, the reaction conditions, the presence of a catalyst, the chemical and physical status of the latter, and other factors have been extensively studied. The purpose of the present Review is not to list all the experiments reported in the literature, but rather to identify trends and provide a comprehensive summary on the role of selected parameters. The role of the catalyst occupies a central place in this Review as a careful control of the metal particle size, particle dispersion on the support, the metastable phase formed under reaction conditions, its possible reconstruction, and faceting strongly influence the diameter of the carbon nanotubes, their structure (number of walls, graphene sheet orientation, chirality), their alignment, and the yield. The identified trends will be compared with recent observations on the growth of graphene. Recent results on metal-free catalysts will be analyzed from a different perspective.
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