• 제목/요약/키워드: single-walled Carbon nanotube

검색결과 213건 처리시간 0.028초

단겹 탄소나노튜브 트랜지스터의 나노습도센서 응용가능성 연구 (Possible application of single-walled carbon nanotube transistors for humidity sensor)

  • 나필선;김효진;이영화;이정오;김진희
    • 센서학회지
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    • 제14권5호
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    • pp.331-336
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    • 2005
  • The influence of water molecule on the electrical properties of single-walled carbon nanotube field effect transistors (SWNT-FETs) was reported. Conductance suppression was observed with the increase of the humidity. This can be explained by doping of the SWNT-FETs, which has p-type semiconductor characteristic, with the water molecules acting as an electron donor. However, after 65 % of humidity, conductance of the SWNT-FETs started to increase again, due to the opening of electron channels. Upon annealing at $400^{\circ}C$ in Ar atmosphere, conductance increases more than 500 %, and the threshold voltage shifts toward further positive gate voltages. The results of this experiment support possible application of single-walled carbon nanotubes for humidity sensing material.

Impacts of surface irregularity on vibration analysis of single-walled carbon nanotubes based on Donnell thin shell theory

  • Selim, Mahmoud M.;Althobaiti, Saad;Yahia, I.S.;Mohammed, Ibtisam M.O.;Hussin, Amira M.;Mohamed, Abdel-Baset A.
    • Advances in nano research
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    • 제12권5호
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    • pp.483-488
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    • 2022
  • The present work is an attempt to study the vibration analysis of the single-walled carbon nanotubes (SWCNTs) under the effect of the surface irregularity using Donnell's model. The surface irregularity represented by the parabolic form. According to Donnell's model and three-dimensional elasticity theory, a novel governing equations and its solution are derived and matched with the case of no irregularity effects. To understand the reaction of the nanotube to the irregularity effects in terms of natural frequency, the numerical calculations are done. The results obtained could provide a better representation of the vibration behavior of an irregular single-walled carbon nanotube, where the aspect ratio (L/d) and surface irregularity all have a significant impact on the natural frequency of vibrating SWCNTs. Furthermore, the findings of surface irregularity effects on vibration SWCNT can be utilized to forecast and prevent the phenomena of resonance of single-walled carbon nanotubes.

Effect of nitrogen doping and hydrogen confinement on the electronic properties of a single walled carbon nanotube

  • Bhat, Bashir Mohi Ud Din;Dar, Jehangir Rashid;Sen, Pratima
    • Carbon letters
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    • 제17권1호
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    • pp.29-32
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    • 2016
  • This paper addresses the effect of dopants on the electronic properties of zigzag (8, 0) semiconducting single walled carbon nanotubes (SWCNTs), using extended Hückel theory combined with nonequilibrium Green’s function formalism. Through appropriate dopant concentrations, the electronic properties of SWCNTs can be modified. Within this context, we present our ongoing investigation on (8, 0) SWCNTs doped with nitrogen. Quantum confinement effects on the electronic properties of the SWCNTs have also been investigated. The obtained results reveal that the electronic properties of SWCNTs are strongly dependent on the dopant concentration and modification of electronic structures by hydrogen confinement.

Electrochemical Determination of 6-Benzylaminopurine (6-BAP) Using a Single-wall Carbon Nanotube-dicetyl Phosphate Film Coated Glassy Carbon Electrode

  • Li, Chunya
    • Bulletin of the Korean Chemical Society
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    • 제27권7호
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    • pp.991-994
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    • 2006
  • Herein, insoluble single-walled carbon nanotube (SWNT) was successfully dispersed into water in the presence of a special kind of surfactant-dicetyl phosphate (DCP), subsequently, a SWNT-DCP composite film coated glassy carbon electrode (GCE) was fabricated. The electrochemical behaviors of 6-benzylaminopurine (6-BAP) at the unmodified GCE and SWNT-DCP modified GCE were examined. It is found that the SWNT-DCP modified GCE remarkably enhances the oxidation peak current of 6-BAP, indicating great potential in the determination of trace level of 6-BAP. Finally, a sensitive and simple voltammetric method with a good linear relationship in the range of ${\times}5.0\;\;10^{-8}\sim 2.5\;{\times}\;10^{-6}$ mol/L, was developed for the determination of 6-BAP. The detection limit is as low as $2.0\;{\times}\;10^{-8}$ mol/L for 3-min accumulation. This newly-proposed method was successfully demonstrated with practical samples.

탄소나노튜브 다발의 압축 및 비틀림 좌굴 거동 (Compressive and Torsional Buckling Behavior of Carbon Nanotube Bundles)

  • 정병우;임장근
    • 대한기계학회논문집A
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    • 제31권8호
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    • pp.862-869
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    • 2007
  • The compressive and torsional buckling behavior of carbon nanotube bundles at room temperature is examined with classical molecular dynamics simulation. The critical compressive load and stiffness of a single carbon nanotube in the bundle are found to be similar to those of individual carbon nanotubes. However, the critical torsional moment and stiffness of a single carbon nanotube in the bundle are found to be higher than those of individual carbon nanotubes. In addition, this study demonstrates that van der Waals interactions between the nanotubes in the bundle significantly affect the critical compressive load of the nanotube bundle.

Immobilization of Lipase on Single Walled Carbon Nanotubes in Ionic Liquid

  • Lee, Han-Ki;Lee, Jae-Kwan;Kim, Mahn-Joo;Lee, Cheol-Jin
    • Bulletin of the Korean Chemical Society
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    • 제31권3호
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    • pp.650-652
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    • 2010
  • A lipase from Pseudomonas cepacia was immobilized onto single walled carbon nanotubes (SWNTs) in two different ways in each of two solvent systems (buffer and ionic liquid). The most efficient immobilization was achieved in ionic liquid (1-butyl-3-methylimidazolium tetrafluoroborate, BMIM-$BF_4$). In this procedure, carbon nanotubes were first functionalized noncovalently with 1-pyrenebutyric acid N-hydroxysuccinimide ester and then subject to the coupling reaction with the lipase in ionic liquid. The resulting immobilized enzyme displayed the highest activity in the transesterification of 1-phenylethyl alcohol in the presence of vinyl acetate in toluene.

Nonlinear vibration properties of a zigzag single-walled carbon nanotube embedded in a polymer matrix

  • Besseghier, Abderrahmane;Heireche, Houari;Bousahla, Abdelmoumen Anis;Tounsi, Abdelouahed;Benzair, Abdelnour
    • Advances in nano research
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    • 제3권1호
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    • pp.29-37
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    • 2015
  • In the current study, the nonlinear vibration properties of an embedded zigzag single-walled carbon nanotube (SWCNT) are investigated. Winkler-type model is used to simulate the interaction of the zigzag SWCNTs with a surrounding elastic medium. The relation between deflection amplitudes and resonant frequencies of the SWCNT is derived through harmonic balance method. The equivalent Young's modulus and shear modulus for zigzag SWCNT are derived using an energy-equivalent model. The amplitude - frequency curves for large-amplitude vibrations are graphically illustrated. The simulation results show that the chirality of zigzag carbon nanolube as well as surrounding elastic medium play more important roles in the nonlinear vibration of the single-walled carbon nanotubes.

Fabrication and Electrical Properties of Highly Organized Single-Walled Carbon Nanotube Networks for Electronic Device Applications

  • Kim, Young Lae
    • 한국세라믹학회지
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    • 제54권1호
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    • pp.66-69
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    • 2017
  • In this study, the fabrication and electrical properties of aligned single-walled carbon nanotube (SWCNT) networks using a template-based fluidic assembly process are presented. This complementary metal-oxide-semiconductor (CMOS)-friendly process allows the formation of highly aligned lateral nanotube networks on $SiO_2/Si$ substrates, which can be easily integrated onto existing Si-based structures. To measure outstanding electrical properties of organized SWCNT devices, interfacial contact resistance between organized SWCNT devices and Ti/Au electrodes needs to be improved since conventional lithographic cleaning procedures are insufficient for the complete removal of lithographic residues in SWCNT network devices. Using optimized purification steps and controlled developing time, the interfacial contact resistance between SWCNTs and contact electrodes of Ti/Au is reached below 2% of the overall resistance in two-probe SWCNT platform. This structure can withstand current densities ${\sim}10^7A{\cdot}cm^{-2}$, equivalent to copper at similar dimensions. Also failure current density improves with decreasing network width.

탄성 보 모델을 이용한 탄소나노튜브의 압축거동해석 (Analysis of Single-Walled Carbon Nanotube under Compression using Elastic Beam Model)

  • 박노정;전윤희;박재균
    • 한국전산구조공학회논문집
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    • 제23권5호
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    • pp.567-575
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    • 2010
  • 탄소나노튜브는 기계적 성질이 매우 뛰어나기 때문에 앞으로 많이 이용될 수 있는 신소재이지만 작은 크기와 특별한 성질 때문에 해석에 어려움이 있으며, 분자 동역학이나 범함수 이론을 이용한 전자시뮬레이션은 계산이 어렵고 시간이 오래 걸리는 단점이 있다. 이러한 단점을 극복하기 위하여 원자 사이에 작용하는 힘을 구조 부재로 치환하는 방법을 사용할 수 있다. 본 연구에서는 0.1nm 길이의 탄성 보를 사용하여 나노튜브를 구성하는 원자 사이의 힘을 묘사하고 선형 압축거동을 해석하였다. 선형 거동은 기존의 다른 방법을 사용한 결과와 잘 일치하였으며, 보 요소의 특성이 적절하게 정해질 경우 비선형 거동의 연구에도 이용될 수 있을 것이다.