• 대한화학회지
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• 제59권5호
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• pp.429-433
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• 2015

The binding ability and hydrogen storage capacity of nitrogen doped carbon nanotube with divacancy (4NDCN_xNT) that is decorated with transition metals was investigated based on density functional theory calculations. Results indicate that scandium shows an ideal reversible hydrogen binding capability with promising system-weight efficiency compared with other transition metals when functionalized with 4ND-CN_xNT. The (Sc/4ND)₁₀-CN_xNT can store up to 50H₂ molecules, corresponding to a maximum gravimetric density of 5.8 wt%. Detailed structural stability and electronic properties were reported as hydrogen molecules were absorbed. It takes about 0.16 eV/H₂ to add one H₂ molecule, which assures reversible storage of H₂ molecules under ambient conditions.

• Transactions on Electrical and Electronic Materials
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• 제9권4호
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• pp.169-172
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• 2008

We attempted to fabricate carbon nanotube field effect transistor (CNT-FET) using single walled carbon nanotube(SWNT) on the heavily doped Si substrate used as a bottom gate, source and drain electrode were fabricated bye-beam lithography on the 500 nm thick $SiO_2$ gate dielectric layer. We investigated electrical and physical properties of this CNT-FET using Scanning Probe Microscope(SPM) and conventional method based on tungsten probe tip technique. The gate length of CNT-FET was 600 nm and the diameter of identified SWNT was about 4 nm. We could observed gating effect and typical p-MOS property from the obtained $V_G-I_{DS}$ curve. The threshold voltage of CNT-FET is about -4.6V and transconductance is 47 nS. In the physical aspect, we could identified SWNT with phase mode of SPM which detecting phase shift by force gradient between cantilever tip and sample surface.

• Korean Chemical Engineering Research
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• 제61권3호
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• pp.456-462
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• 2023

탄소나토튜브를 투명 전극에 활용하기 위한 필수요소인 정제과정없이 무정제 단일벽 탄소나노튜브(single-walled carbon nanotube, SWCNT)와 은나노와이어(silver nanowire) 분산액을 제조하여 폴리에틸렌 테레프탈레이트(polyethylene terephthalate, PET) 필름에 바 코팅을 이용하여 전기전도성 투명전극을 제조하였다. PET 기판 위에 SWCNT 및 은 나노와이어를 각각 포함하는 코팅층을 상호 교차시켜 적층함으로서 은나노와이어의 전기 전도도와 투과도를 극대화시키고 헤이즈 (haze)가 증가되는 단점을 극복하기 위해 SWCNT를 도입하였고, 무정제 SWCNT내에 존재하는 금속 촉매의 산화에 의해서 항온항습 테스트 후 저항이 급격하게 증가하는 문제를 은 나노와이어가 전기적 네트워크 형성에 기여하여 산화에 대한 안정성을 확보할 수 있었다. SWCNT함량이 0.025 wt% 인 분산액을 PET 기판에 먼저 코팅하고 그 위에 은 나노와이어의 함량이 0.05 wt%인 분산액을 코팅한 투명전극의 시트 저항은 47 Ω/□, 투과도는 96.72%, 헤이즈는 1.93% 로 전기적 광학적 특성이 우수하게 나왔고, 산화 안정성 평가를 위한 항온 항습 실험 후 시트 저항의 변화율이 6.4% 로 적게 나타나서 장기적 사용에 적합하다는 것을 알 수 있었다. 무정제 SWCNT 사용함으로 저비용, 친환경 하이브리드 투명전극을 상업적으로 활용 가능한 수준의 제품이 개발되었다.

• 폴리머
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• 제36권3호
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• pp.364-371
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• 2012

폴리스티렌(PS)/단일벽 탄소나노튜브(SWCNT) 나노복합재료를 라텍스 기술로 제조하여 계면활성제(SDS) 첨가에 따른 SWCNT의 분산 정도와 나노복합재료의 유변학적, 전기적 물성을 고찰하였다. 나노복합재료는 단분산 PS 입자에 SDS를 첨가한 SWCNT 분산액을 혼합한 후 동결건조하여 제조하였다. SDS 함량이 증가함에 따라 나노튜브의 분산성이 향상되어 나노복합재료의 저장 탄성률과 복소 점도는 증가하지만, 지나치게 증가시킨 경우에는 저분자량의 SDS로 인해 감소하는 결과를 보여주었다. 전기 전도도는 SDS를 첨가함에 따라 급격히 향상된 후 큰 변화를 보이지 않았다. 이는 나노튜브의 분산성 향상에 의한 전기 전도도 증가와 SDS 도포에 의한 SWCNT의 전기 전도도 저하의 경쟁에 의한 것으로 추론된다. SDS를 SWCNT 함량의 2배로 첨가한 경우가 나노복합재료의 전기 전도도 및 사용 물성 향상에 최적 조건이었다. 이 경우 전도성을 부여하는 SWCNT의 임계 함량은 1 wt% 이하에서 나타났다.

• Journal of Electrochemical Science and Technology
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• 제3권3호
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• pp.143-148
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• 2012

The unique effects of highly conductive conducting polymer/SWNT (single walled carbon nanotube) composite nanoparticles in electric double layer capacitors are studied for the enhancement of the adhesive properties, specific capacitance and power characteristics of the electrode. Because the conducting polymer/SWNT composite material, which is believed to act as a polymer binder, an active material for charge storage and a conducting agent, is well distributed on the activated carbon, greatly enhanced adhesion properties, cell capacitance and power characteristics were obtained.

• Journal of Electrical Engineering and Technology
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• 제10권3호
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• pp.1169-1173
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• 2015

This paper presents vertical carbon nanotube (CNT) field effect transistors (FETs). For the first time, the author successfully fabricated vertical CNT-based FETs on an anodized aluminum oxide (AAO) template by using atomic layer deposition (ALD). Single walled CNTs were vertically grown and aligned with the vertical pores of an AAO template. By using ALD, a gate oxide material (Al₂O₃) and a gate metal (Au) were centrally located inside each pore, allowing the vertical CNTs grown in the pores to be individually gated. Characterizations of the gated/vertical CNTs were carried and the successful gate integration with the CNTs was confirmed.

• 새물리
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• 제68권11호
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• pp.1167-1172
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• 2018

탄소 나노 튜브는 탄소 원자들이 육각형의 벌집모양으로 서로 연결된 고분자 탄소동소체로 다중벽일 경우 $3000W{\cdot}m^{-1}{\cdot}K^{-1}$, 단일벽일 경우 $6000W{\cdot}m^{-1}{\cdot}K^{-1}$ 정도로 매우 높은 열전도도를 보인다. 본 연구에서는 단일 빔과 이중 빔 방법으로 열렌즈 효과를 이용하여, 1.5 M 다중벽 탄소 나노튜브 분산액의 투과율과 열확산도를 측정하였다. 단일 레이저 빔의 진행방향으로 시료를 움직이는 z-scan 방법을 통해 비선형 광학계수들을 구하고, 이중 레이저 빔을 이용하여 열확산도를 측정하였다. 펌프 빔으로는 파장 532 nm이고 세기가 100 mW인 DPSS (Diode-pumped solid state, DPSS) 레이저를 사용하였고, 프로브빔으로는 파장이 633 nm이며 세기가 5 mW인 He-Ne 레이저를 사용하였다. 실험 결과 농도가 9.99, 11.10, 16.65, 19.98 mM일 때 비선형 흡수계수는 각각 0.046, 0.051, 0.136, 0.169 m/W였다. 또한 비선형 굴절률은 0.20, 0.51, 1.25, $1.32{\times}10^{-11}m^2/W$였고, 열확산도 평균치는 $1.33{\times}10^{-6}m^2/s$이었다.

• 센서학회지
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• 제19권2호
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• pp.160-167
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• 2010

In this paper, we fabricated the optoelectronic device based on Cadmium selenide(CdSe) nanocrystal quantum dots (NQDs)/single-walled carbon nanotubes(SWNTs) heterostructure using dieletrophoretic force. The efficient charge transfer phenomena from CdSe to SWNT make CdSe-Pyridine(py)-SWNT unique heterostructures for novel optoelectronic device. The conductivity of CdSe-py-SWNT was increased when it was exposed at ultra violet(UV) lamp, and varied as a function of wavelength of incident light.

• Bulletin of the Korean Chemical Society
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• 제35권10호
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• pp.3035-3040
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• 2014

A new efficient catalytic method for aza/thia-Michael addition reactions of amines/thiols with higher product yields has been developed. Combining single-walled carbon nanotubes (SWCNT) with triethylammonium hydrogen phosphate (TEAP) ionic liquid (IL) can work as a catalyst. We utilized Raman spectroscopy to gain insight into the interactions between IL and SWCNT. The interactions between SWCNT with TEAP were confirmed by the increasing intensity ratios and spectral shift in wavelength of the Raman D and G bands of SWCNT. Further, the morphology of the resulting composite materials of TEAP and SWCNT was determined by using scanning electron microscopy (SEM). Higher product yield in reduced reaction time is the key advantage of using bucky gel as a catalyst for Michael reaction.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2009년도 춘계학술발표대회
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• pp.31.2-31.2
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• 2009

In this research, single walled carbon nano-tube film was manufactured with spray coating method on glass for application as transparent heat element. SWNTs solution to be used for spraying is obtained by dispersion of 0.01 wt% purified SWNTs in dimethylformamide (DMF) solution through ultrasonification and centrifugation. The transmittance and sheet resistance of SWNTs film were determined by the number of spray injection. Manufactured SWNTs film will have sheet resistance range of $200\;\Omega/\square-900\;\Omega/\square$ at transmittance range of 70-90 %. Heat generation characteristic of SWNTs film was measured by applying constant DC voltage of 15V. The result confirmed that SWNTs film with sheet resistance of $200\;\Omega/\square$ reaches surface temperature of $80^{\circ}C$ within several seconds. In addition, PET coating film was coated on top of the SWNTs film by using laminator in order to solve weak adhesive property of the spray coated SWNTs film on the substrate as well as to maintain its electrical and optical properties.