1
|
Erkens M, Levshov D, Wenseleers W, Li H, Flavel BS, Fagan JA, Popov VN, Avramenko M, Forel S, Flahaut E, Cambré S. Efficient Inner-to-Outer Wall Energy Transfer in Highly Pure Double-Wall Carbon Nanotubes Revealed by Detailed Spectroscopy. ACS NANO 2022; 16:16038-16053. [PMID: 36167339 PMCID: PMC9620404 DOI: 10.1021/acsnano.2c03883] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 09/07/2022] [Indexed: 06/16/2023]
Abstract
The coaxial stacking of two single-wall carbon nanotubes (SWCNTs) into a double-wall carbon nanotube (DWCNT), forming a so-called one-dimensional van der Waals structure, leads to synergetic effects that dramatically affect the optical and electronic properties of both layers. In this work, we explore these effects in purified DWCNT samples by combining absorption, wavelength-dependent infrared fluorescence-excitation (PLE), and wavelength-dependent resonant Raman scattering (RRS) spectroscopy. Purified DWCNTs are obtained by careful solubilization that strictly avoids ultrasonication or by electronic-type sorting, both followed by a density gradient ultracentrifugation to remove unwanted SWCNTs that could obscure the DWCNT characterization. Chirality-dependent shifts of the radial breathing mode vibrational frequencies and transition energies of the inner and outer DWCNT walls with respect to their SWCNT analogues are determined by advanced two-dimensional fitting of RRS and PLE data of DWCNT and their reference SWCNT samples. This exhaustive data set verifies that fluorescence from the inner DWCNT walls of well-purified samples is severely quenched through efficient energy transfer from the inner to the outer DWCNT walls. Combined analysis of the PLE and RRS results further reveals that this transfer is dependent on the inner and outer wall chirality, and we identify the specific combinations dominant in our DWCNT samples. These obtained results demonstrate the necessity and value of a combined structural characterization approach including PLE and RRS spectroscopy for bulk DWCNT samples.
Collapse
Affiliation(s)
- Maksiem Erkens
- Nanostructured
and Organic Optical and Electronic Materials, Department of Physics, University of Antwerp, B-2610 Antwerp, Belgium
| | - Dmitry Levshov
- Nanostructured
and Organic Optical and Electronic Materials, Department of Physics, University of Antwerp, B-2610 Antwerp, Belgium
| | - Wim Wenseleers
- Nanostructured
and Organic Optical and Electronic Materials, Department of Physics, University of Antwerp, B-2610 Antwerp, Belgium
| | - Han Li
- Institute
of Nanotechnology, Karlsruhe Institute of
Technology, 76344 Eggenstein-Leopoldshafen, Germany
| | - Benjamin S. Flavel
- Institute
of Nanotechnology, Karlsruhe Institute of
Technology, 76344 Eggenstein-Leopoldshafen, Germany
| | - Jeffrey A. Fagan
- Materials
Science and Engineering Division, National
Institute of Standards and Technology, 20899 Gaithersburg, Maryland, United States
| | | | - Marina Avramenko
- Nanostructured
and Organic Optical and Electronic Materials, Department of Physics, University of Antwerp, B-2610 Antwerp, Belgium
| | - Salomé Forel
- Nanostructured
and Organic Optical and Electronic Materials, Department of Physics, University of Antwerp, B-2610 Antwerp, Belgium
- Laboratoire
des Multimatériaux et Interfaces, UMR CNRS 5615, Univ Lyon, Université Claude Bernard Lyon 1, F-69622 Villeurbanne, France
| | - Emmanuel Flahaut
- CIRIMAT,
UMR 5085, CNRS-INP-UPS, Université
Toulouse 3 Paul Sabatier, 118 route de Narbonne, F-31062 Toulouse cedex 9, France
| | - Sofie Cambré
- Nanostructured
and Organic Optical and Electronic Materials, Department of Physics, University of Antwerp, B-2610 Antwerp, Belgium
| |
Collapse
|
2
|
Cambré S, Liu M, Levshov D, Otsuka K, Maruyama S, Xiang R. Nanotube-Based 1D Heterostructures Coupled by van der Waals Forces. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e2102585. [PMID: 34355517 DOI: 10.1002/smll.202102585] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Revised: 07/19/2021] [Indexed: 06/13/2023]
Abstract
1D van der Waals heterostructures based on carbon nanotube templates are raising a lot of excitement due to the possibility of creating new optical and electronic properties, by either confining molecules inside their hollow core or by adding layers on the outside of the nanotube. In contrast to their 2D analogs, where the number of layers, atomic type and relative orientation of the constituting layers are the main parameters defining physical properties, 1D heterostructures provide an additional degree of freedom, i.e., their specific diameter and chiral structure, for engineering their characteristics. The current state-of-the-art in synthesizing 1D heterostructures are discussed here, in particular focusing on their resulting optical properties, and details the vast parameter space that can be used to design heterostructures with custom-built properties that can be integrated into a large variety of applications. First, the effects of van der Waals coupling on the properties of the simplest and best-studied 1D heterostructure, namely a double-walled carbon nanotube, are described, and then heterostructures built from the inside and the outside are considered, which all use a nanotube as a template, and, finally, an outlook is provided for the future of this research field.
Collapse
Affiliation(s)
- Sofie Cambré
- Nanostructured and Organic Optical and Electronic Materials, Department of Physics, University of Antwerp, Antwerp 2610, Belgium
| | - Ming Liu
- Department of Mechanical Engineering, The University of Tokyo, Tokyo, 113-8656, Japan
| | - Dmitry Levshov
- Nanostructured and Organic Optical and Electronic Materials, Department of Physics, University of Antwerp, Antwerp 2610, Belgium
| | - Keigo Otsuka
- Department of Mechanical Engineering, The University of Tokyo, Tokyo, 113-8656, Japan
| | - Shigeo Maruyama
- Department of Mechanical Engineering, The University of Tokyo, Tokyo, 113-8656, Japan
| | - Rong Xiang
- Department of Mechanical Engineering, The University of Tokyo, Tokyo, 113-8656, Japan
| |
Collapse
|
3
|
Davardoostmanesh M, Ahmadzadeh H, Goharshadi EK, Meshkini A, Sistanipour E. Graphitic carbon nitride nanosheets prepared by electrophoretic size fractionation as an anticancer agent against human bone carcinoma. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2020; 111:110803. [DOI: 10.1016/j.msec.2020.110803] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 02/04/2020] [Accepted: 03/02/2020] [Indexed: 02/06/2023]
|
4
|
Yang F, Wang M, Zhang D, Yang J, Zheng M, Li Y. Chirality Pure Carbon Nanotubes: Growth, Sorting, and Characterization. Chem Rev 2020; 120:2693-2758. [PMID: 32039585 DOI: 10.1021/acs.chemrev.9b00835] [Citation(s) in RCA: 147] [Impact Index Per Article: 36.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Single-walled carbon nanotubes (SWCNTs) have been attracting tremendous attention owing to their structure (chirality) dependent outstanding properties, which endow them with great potential in a wide range of applications. The preparation of chirality-pure SWCNTs is not only a great scientific challenge but also a crucial requirement for many high-end applications. As such, research activities in this area over the last two decades have been very extensive. In this review, we summarize recent achievements and accumulated knowledge thus far and discuss future developments and remaining challenges from three aspects: controlled growth, postsynthesis sorting, and characterization techniques. In the growth part, we focus on the mechanism of chirality-controlled growth and catalyst design. In the sorting part, we organize and analyze existing literature based on sorting targets rather than methods. Since chirality assignment and quantification is essential in the study of selective preparation, we also include in the last part a comprehensive description and discussion of characterization techniques for SWCNTs. It is our view that even though progress made in this area is impressive, more efforts are still needed to develop both methodologies for preparing ultrapure (e.g., >99.99%) SWCNTs in large quantity and nondestructive fast characterization techniques with high spatial resolution for various nanotube samples.
Collapse
Affiliation(s)
- Feng Yang
- Beijing National Laboratory for Molecular Science, Key Laboratory for the Physics and Chemistry of Nanodevices, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Meng Wang
- Beijing National Laboratory for Molecular Science, Key Laboratory for the Physics and Chemistry of Nanodevices, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Daqi Zhang
- Beijing National Laboratory for Molecular Science, Key Laboratory for the Physics and Chemistry of Nanodevices, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Juan Yang
- Beijing National Laboratory for Molecular Science, Key Laboratory for the Physics and Chemistry of Nanodevices, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| | - Ming Zheng
- Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, United States
| | - Yan Li
- Beijing National Laboratory for Molecular Science, Key Laboratory for the Physics and Chemistry of Nanodevices, College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, China
| |
Collapse
|
5
|
Fagan JA. Aqueous two-polymer phase extraction of single-wall carbon nanotubes using surfactants. NANOSCALE ADVANCES 2019; 1:3307-3324. [PMID: 36133572 PMCID: PMC9417344 DOI: 10.1039/c9na00280d] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 07/11/2019] [Indexed: 05/09/2023]
Abstract
This review details the current state of the art in aqueous two-phase extraction (ATPE) based separations of surfactant dispersed single-wall carbon nanotubes by their chemical species, i.e., (n,m) structure, semiconducting or metallic nature, and enantiomeric handedness. Discussions of the factors affecting each separation, including workflow effects, variations of different surfactant and nanotube materials, and the underlying physical mechanism are presented. Lastly an outlook on the applications of ATPE at bench scale and implementation to larger scales is discussed, along with identification of research directions that could further support ATPE development.
Collapse
Affiliation(s)
- Jeffrey A Fagan
- Materials Science and Engineering Division, National Institute of Standards and Technology Gaithersburg MD USA 20899
| |
Collapse
|
6
|
Pei H, Sha R, Wang X, Zheng M, Fan C, Canary JW, Seeman NC. Organizing End-Site-Specific SWCNTs in Specific Loci Using DNA. J Am Chem Soc 2019; 141:11923-11928. [PMID: 31282152 DOI: 10.1021/jacs.9b03432] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Single-wall carbon nanotubes (SWCNTs) are known to embody many desirable features for nanoelectronic and photonic applications, including excellent electronic and optical properties and mechanical robustness. To utilize these species in a bottom-up nanotechnological approach, it is necessary to be able to place them in precise absolute positions within a larger framework, without disturbing the conduction surface. Although it is well-known how to orient one or two nanotubes on a DNA origami, precise placement has eluded investigators previously. Here, we report a method of attaching a strand of DNA on the reactive end of a SWCNT, and then of using that DNA strand to place the nanotube at a specific site on a 2D DNA origami raft. We demonstrate that it is possible to place one or two nanotubes on such a DNA origami raft.
Collapse
Affiliation(s)
- Hao Pei
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecule Engineering , East China Normal University , Shanghai 200241 , P.R. China
| | - Ruojie Sha
- Department of Chemistry , New York University , 100 Washington Square East , New York , New York 10003 , United States
| | - Xiwei Wang
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecule Engineering , East China Normal University , Shanghai 200241 , P.R. China
| | - Ming Zheng
- Materials Science and Engineering Division , National Institute of Standards and Technology , 100 Bureau Drive , Gaithersburg , Maryland 20899 , United States
| | - Chunhai Fan
- School of Chemistry and Chemical Engineering, and Institute of Molecular Medicine, Renji Hospital, School of Medicine , Shanghai Jiao Tong University , Shanghai 200240 , China
| | - James W Canary
- Department of Chemistry , New York University , 100 Washington Square East , New York , New York 10003 , United States
| | - Nadrian C Seeman
- Department of Chemistry , New York University , 100 Washington Square East , New York , New York 10003 , United States
| |
Collapse
|
7
|
Wang P, Peng Z, Li M, Wang Y. Stretchable Transparent Conductive Films from Long Carbon Nanotube Metals. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2018; 14:e1802625. [PMID: 30091525 PMCID: PMC6482951 DOI: 10.1002/smll.201802625] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Indexed: 05/09/2023]
Abstract
Flexible transparent conductors are an enabling component for large-area flexible displays, wearable electronics, and implantable medical sensors that can wrap around and move with the body. However, conventional conductive materials decay quickly under tensile strain, posing a significant hurdle for functional flexible devices. Here, we show that high electrical conductivity, mechanical stretchability, and optical transparency can be simultaneously attained by compositing long metallic double-walled carbon nanotubes with a polydimethylsiloxane substrate. When stretched to 100% tensile strain, thin films incorporating these long nanotubes (≈3.2 µm on average) achieve a record high conductivity of 3316 S cm-1 at 100% tensile strain and 85% optical transmittance, which is 194 times higher than that of short nanotube controls (≈0.8 µm on average). Moreover, the high conductivity can withstand more than 1000 repeated stretch-release cycles (switching between 100% and 0% strain) with a retention approaching 96%, whereas the short nanotube controls exhibit only 10%. Mechanistic studies reveal that long tubes can bridge the microscale gaps generated during stretching, thereby maintaining high electrical conductivity. When mounted on human joints, this elastic transparent conductor can accommodate large motions to provide stable, high current output. These results point to transparent conductors capable of attaining high electrical conductivity and optical transmittance under mechanical strain to allow large shape changes that may take place in the operation and use of flexible electronics.
Collapse
Affiliation(s)
- Peng Wang
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA,
| | - Zhiwei Peng
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA,
| | - Muxiao Li
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA,
| | - YuHuang Wang
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA,
- Maryland NanoCenter, University of Maryland, College Park, MD 20742, USA
| |
Collapse
|
8
|
Zaslavsky BY, Uversky VN. In Aqua Veritas: The Indispensable yet Mostly Ignored Role of Water in Phase Separation and Membrane-less Organelles. Biochemistry 2018; 57:2437-2451. [PMID: 29303563 DOI: 10.1021/acs.biochem.7b01215] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Despite the common practice of presenting structures of biological molecules on an empty background and the assumption that interactions between biological macromolecules take place within the inert solvent, water represents an active component of various biological processes. This Perspective addresses indispensable, yet mostly ignored, roles of water in biological liquid-liquid phase transitions and in the biogenesis of various proteinaceous membrane-less organelles. We point out that changes in the structure of water reflected in the changes in its abilities to donate and/or accept hydrogen bonds and participate in dipole-dipole and dipole-induced dipole interactions in the presence of various solutes (ranging from small molecules to synthetic polymers and biological macromolecules) might represent a driving force for the liquid-liquid phase separation, define partitioning of various solutes in formed phases, and define the exceptional ability of intrinsically disordered proteins to be engaged in the formation of proteinaceous membrane-less organelles.
Collapse
Affiliation(s)
| | - Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine , University of South Florida , Tampa , Florida 33612 , United States.,Laboratory of New Methods in Biology , Institute for Biological Instrumentation of the Russian Academy of Sciences , Pushchino , Moscow Region 142290 , Russia
| |
Collapse
|
9
|
Li H, Gordeev G, Wasserroth S, Chakravadhanula VSK, Neelakandhan SKC, Hennrich F, Jorio A, Reich S, Krupke R, Flavel BS. Inner- and outer-wall sorting of double-walled carbon nanotubes. NATURE NANOTECHNOLOGY 2017; 12:1176-1182. [PMID: 28967894 DOI: 10.1038/nnano.2017.207] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Accepted: 09/05/2017] [Indexed: 06/07/2023]
Abstract
Double-walled carbon nanotubes (DWCNTs) consist of two coaxially aligned single-walled carbon nanotubes (SWCNTs), and previous sorting methods only achieved outer-wall electronic-type selectivity. Here, a separation technique capable of sorting DWCNTs by semiconducting (S) or metallic (M) inner- and outer-wall electronic type is presented. Electronic coupling between the inner and outer wall is used to alter the surfactant coating around each of the DWCNT types, and aqueous gel permeation is used to separate them. Aqueous methods are used to remove SWCNT species from the raw material and prepare enriched DWCNT fractions. The enriched DWCNT fractions are then transferred into either chlorobenzene or toluene using the copolymer PFO-BPy to yield the four inner@outer combinations of M@M, M@S, S@M and S@S. The high purity of the resulting fractions is verified by absorption measurements, transmission electron microscopy, atomic force microscopy, resonance Raman mapping and high-density field-effect transistor devices.
Collapse
Affiliation(s)
- Han Li
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
| | - Georgy Gordeev
- Department of Physics, Freie Universität Berlin, 14195 Berlin, Germany
| | - Sören Wasserroth
- Department of Physics, Freie Universität Berlin, 14195 Berlin, Germany
| | - Venkata Sai Kiran Chakravadhanula
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
- Helmholtz Institute Ulm Electrochemical Energy Storage, 89081 Ulm, Germany
| | - Shyam Kumar Chethala Neelakandhan
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
- Institute of Materials Science, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Frank Hennrich
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
| | - Ado Jorio
- Department of Physics, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Stephanie Reich
- Department of Physics, Freie Universität Berlin, 14195 Berlin, Germany
| | - Ralph Krupke
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
- Institute of Materials Science, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Benjamin Scott Flavel
- Institute of Nanotechnology, Karlsruhe Institute of Technology, 76021 Karlsruhe, Germany
- Institute of Materials Science, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| |
Collapse
|
10
|
Streit JK, Fagan JA, Zheng M. A Low Energy Route to DNA-Wrapped Carbon Nanotubes via Replacement of Bile Salt Surfactants. Anal Chem 2017; 89:10496-10503. [PMID: 28856894 DOI: 10.1021/acs.analchem.7b02637] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
DNA-wrapped carbon nanotubes are a class of bionano hybrid molecules that have enabled carbon nanotube sorting, controlled assembly, and biosensing and bioimaging applications. The current method of synthesizing these hybrids via direct sonication of DNA/nanotube mixtures is time-consuming and not suitable for high-throughput synthesis and combinatorial sequence screening. Additionally, the direct sonication method does not make use of nanotubes presorted by extensively developed surfactant-based methods, is not effective for large diameter (>1 nm) tubes, and cannot maintain secondary and tertiary structural and functional domains present in certain DNA sequences. Here, we report a simple, quick, and robust process to produce DNA-wrapped carbon nanotube hybrids with nanotubes of broad diameter range and DNA of arbitrary sequence. This is accomplished by exchanging strong binding bile salt surfactant coating with DNA in methanol/water mixed solvent and subsequent precipitation with isopropyl alcohol. The exchange process can be completed within 10 min and converts over 90% nanotubes into the DNA wrapped form. Applying the exchange process to nanotubes presorted by surfactant-based methods, we show that the resulting DNA-wrapped carbon nanotubes can be further sorted to produce nanotubes with defined handedness, helicity, and endohedral filling. The exchange method greatly expands the structural and functional variety of DNA-wrapped carbon nanotubes and opens possibilities for DNA-directed assembly of structurally sorted nanotubes and high-throughput screening of properties that are controlled by the wrapping DNA sequences.
Collapse
Affiliation(s)
- Jason K Streit
- Materials Science and Engineering Division, National Institute of Standards and Technology , 100 Bureau Drive, Gaithersburg, Maryland 20899-8542, United States
| | - Jeffrey A Fagan
- Materials Science and Engineering Division, National Institute of Standards and Technology , 100 Bureau Drive, Gaithersburg, Maryland 20899-8542, United States
| | - Ming Zheng
- Materials Science and Engineering Division, National Institute of Standards and Technology , 100 Bureau Drive, Gaithersburg, Maryland 20899-8542, United States
| |
Collapse
|
11
|
Evans GP, Buckley DJ, Skipper NT, Parkin IP. Switchable changes in the conductance of single-walled carbon nanotube networks on exposure to water vapour. NANOSCALE 2017; 9:11279-11287. [PMID: 28758671 DOI: 10.1039/c7nr02141k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We have discovered that wrapping single-walled carbon nanotubes (SWCNTs) with ionic surfactants induces a switch in the conductance-humidity behaviour of SWCNT networks. Residual cationic vs. anionic surfactant induces a respective increase or decrease in the measured conductance across the SWCNT networks when exposed to water vapour. The magnitude of this effect was found to be dependent on the thickness of the deposited SWCNT films. Previously, chemical sensors, field effect transistors (FETs) and transparent conductive films (TCFs) have been fabricated from aqueous dispersions of surfactant functionalised SWCNTs. The results reported here confirm that the electrical properties of such components, based on randomly orientated SWCNT networks, can be significantly altered by the presence of surfactant in the SWCNT layer. A mechanism for the observed behaviour is proposed based on electrical measurements, Raman and UV-Vis-NIR spectroscopy. Additionally, the potential for manipulating the sensitivity of the surfactant functionalised SWCNTs to water vapour for atmospheric humidity sensing was evaluated. The study also presents a simple method to establish the effectiveness of surfactant removal techniques, and highlights the importance of characterising the electrical properties of SWCNT-based devices in both dry and humid operating environments for practical applications.
Collapse
Affiliation(s)
- Gwyn P Evans
- Department of Security and Crime Science, University College London, 35 Tavistock Sq., London, WC1H 9EZ, UK and Department of Chemistry, University College London, 20 Gordon St., London, WC1H 0AJ, UK.
| | - David J Buckley
- Department of Chemistry, University College London, 20 Gordon St., London, WC1H 0AJ, UK.
| | - Neal T Skipper
- Department of Physics and Astronomy, University College London, Gower Street, London, WC1E 6BT, UK and London Centre for Nanotechnology, 17-19 Gordon Street, London WC1H 0AH, UK
| | - Ivan P Parkin
- Department of Chemistry, University College London, 20 Gordon St., London, WC1H 0AJ, UK.
| |
Collapse
|