• Nano
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• 제13권11호
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• pp.1850134.1-1850134.10
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• 2018

Increasing active sites and enhancing electric conductivity are critical factors to improve sensing performance toward phenol. Herein, Ni nanoparticle was successfully anchored on acidified multiwalled carbon nanotube (a-MWCNT) surface by electroless plating technique to avoid Ni nanoparticle agglomeration and guarantee high conductivity. The crystal structure, phase composition and surface morphology were characterized by XRD, SEM and TEM measurement. The as-prepared Ni/a-MWCNT nanohybrid was immobilized onto glassy carbon electrode (GCE) surface for constructing phenol sensor. The phenol sensing performance indicated that Ni/a-MWCNT/GCE exhibited an amazing detection performance with rapid response time of 4 s, a relatively wide detection range from 0.01 mM to 0.48 mM, a detection limit of $7.07{\mu}M$ and high sensitivity of $566.2{\mu}A\;mM^{-1}\;cm^{-2}$. The superior selectivity, reproducibility, stability and applicability in real sample of Ni/a-MWCNT/GCE endowed it with potential application in discharged wastewater.

• 폴리머
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• 제31권5호
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• pp.422-427
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• 2007

반도전층은 전력케이블의 도선과 고분자 절연층 사이에 위치하고 전기저항이 약 ${\sim}10^2{\Omega}cm$인 얇은 고분자층이다. 현재 일반적으로 사용되는 반도전층 소재는 카본블랙이 30 wt% 이상 보강된 고분자 복합체이다. 본 연구에서는 카본나노튜브(CNT)가 보강된 새로운 반도전층 재료를 제시하였다. 여러 가지 고분자 형태와 이중충전제 시스템을 적용하여 용액혼합 및 침전법으로 CNT가 보강된 고분자 나노복합체를 제조하였다. 기계적, 열적, 전기적 특성을 고분자 형태와 CNT와 카본블랙의 첨가비를 달리한 이중충전제 시스템의 함수로 조사하였다. 복합체의 전기저항특성은 고분자 매트릭스의 결정화도와 밀접한 관련이 있었다. 즉, 결정화도가 감소함에 따라 일정한 수준의 결정화도까지 전기저항이 선형적으로 감소하였고, 그 이하에서는 일정한 값을 나타내었다. 이중충전제 시스템 역시 전기적 저항에 영향을 미쳤다. CNT만으로 보강된 나노복합체가 가장 낮은 전기적 저항특성을 보였다. 소량의 카본블랙이 첨가되면 결정화도가 급격히 증가하고 결국 전기저항의 증가를 초래하였다.

• Bulletin of the Korean Chemical Society
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• 제31권6호
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• pp.1589-1595
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• 2010

In order to effective degradation of organic dye both under visible light or ultrasonic irradiation, the MWCNTs (multiwalled carbon nanotube) deposited with Fe and $TiO_2$ were prepared by a modified sol-gel method. The Fe/$TiO_2$-MWCNT catalyst was characterized by surface area of BET, scanning electron microscope (SEM), Transmission Electron Microscope (TEM), X-ray diffraction (XRD), and energy dispersive X-ray (EDX) and ultraviolet-visible (UV-vis) spectroscopy. The low intensity visible light and low power ultrasound was as an irradiation source and the methylene blue (MB) was choose as the model organic dye. Then degradation experiments were carried out in present of undoped $TiO_2$, Fe/$TiO_2$ and Fe/$TiO_2$-MWCNT catalysts. Through the degradation of MB solution, the results showed the feasible and potential use of Fe/$TiO_2$-MWCNT catalyst under visible light and ultrasonic irradiation due to the enhanced formation of reactive radicals as well as the possible visible light and the increase of ultrasound-induced active surface area of the catalyst. After addition of $H_2O_2$, the MB degradation rates have been accelerated, especially with Fe/$TiO_2$-MWCNT catalyst, in case of that the photo-Fenton reaction occurred. The sonophotocatalysis was always faster than the respective individual processes due to the more formation of reactive radicals as well as the increase of the active surface area of Fe/$TiO_2$-MWCNT catalyst.

• 폴리머
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• 제35권5호
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• pp.472-477
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• 2011

다중벽 탄소나노튜브(MWNT)의 표면이 산성기로 처리된 MWNT가 polyacrylonitrile(PAN) 섬유의 열적, 기계적 물성에 미치는 영향을 알아 보고자 질산, 황산으로 처리한 MWNT(O-MWNT)를 디아조늄염 반응을 이용하여 MWNT 표면에 이소프탈산(isophthalic acid)을 추가로 도입하였다. O-MWNT와 비교하여 볼 때 이소프탈산으로 처리된 MWNT(IPA-MWNT)가 극성용매 내에서 더 우수한 분산 안정성을 나타내었으며 이를 호모 PAN과 혼합하여 필름을 제조한 후 공기 중에서 열안정화 반응을 모사하였을 때 호모 PAN과 비교시 발열량이 감소하였다. PAN 공중합체와 IPA-MWNT를 혼합한 용액을 전도성 수조 콜렉터를 이용하여 전기방사를 한 결과 연속상의 배향된 섬유제조가 가능하였다. 1 wt%의 IPA-MWNT를 포함한 연속상의 전기방사된 PAN 섬유는 순수한 PAN 섬유와 비교하여 볼 때 인장강도가 100% 증가하였으며, 탄성률은 160% 증가되었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.264-264
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• 2010

Single-walled carbon nanotubes (SWCNTs) were grown on a Si wafer by using thermal chemical vapor deposition (t-CVD). We investigated the effect of the catalyst deposition rate on the types of CNTs grown on the substrate. In general, smaller islands of catalyst occur by agglomeration of a catalyst layer upon annealing as the catalyst layer becomes thinner, which results in the growth of CNTs with smaller diameters. For the same thickness of catalyst, a slower deposition rate will cause a more uniformly thin catalyst layer, which will be agglomerated during annealing, producing smaller catalyst islands. Thus, we can expect that the smaller-diameter CNTs will grow on the catalyst deposited with a lower rate even for the same thickness of catalyst. The 0.5-nm-thick Fe served as a catalyst, underneath which Al was coated as a catalyst support as well as a diffusion barrier on the Si substrate. The catalyst layers were. coated by using thermal evaporation. The deposition rates of the Al and Fe layers varied to be 90, 180 sec/nm and 70, 140 sec/nm, respectively. We prepared the four different combinations of the deposition rates of the AI and Fe layers. CNTs were synthesized for 10 min by flowing 60 sccm of Ar and 60 sccm of $H_2$ as a carrier gas and 20 sccm of $C_2H_2$ as a feedstock at 95 torr and $810^{\circ}C$. The substrates were subject to annealing for 20 sec for every case to form small catalyst islands prior to CNT growth. As-grown CNTs were characterized by using field emission scanning electron microscopy, high resolution transmission electron microscopy, Raman spectroscopy, UV-Vis NIR spectroscopy, and atomic force microscopy. The fast deposition of both the Al and Fe layers gave rise to the growth of thin multiwalled CNTs with the height of ${\sim}680\;{\mu}m$ for 10 min while the slow deposition caused the growth of ${\sim}800\;{\mu}m$ high SWCNTs. Several radial breathing mode (RBM) peaks in the Raman spectra were observed at the Raman shifts of $113.3{\sim}281.3\;cm^{-1}$, implying the presence of SWCNTs (or double-walled CNTs) with the tube diameters 2.07~0.83 nm. The Raman spectra of the as-grown SWCNTs showed very low G/D peak intensity ratios, indicating their low defect concentrations.