| 학회 |
한국재료학회 |
| 학술대회 |
2011년 봄 (05/26 ~ 05/27, 제주 휘닉스 아일랜드) |
| 권호 |
17권 1호 |
| 발표분야 |
B. Nanomaterials and Processing Technology((나노소재기술) |
| 제목 |
촉매 어닐링 시간 변화에 따른 이중벽 탄소나노튜브의 수직성장 특성 (Characteristics of vertically aligned double walled carbon nanotubes grown with an annealing time of catalyst) |
| 초록 |
Double-walled carbon nanotubes (DWCNTs) were grown on a Si wafer by using thermal chemical vapor deposition (TCVD). We investigated the dependence of the DWCNT growth on the annealing time of the catalyst layer grown on the substrate. Typically, the morphology of catalyst particles are constantly changed in a series of arrangements during the annealing and initial CNT growth stages. 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. CNTs were synthesized for 10 min by flowing 60 sccm of Ar and 60 sccm of H2 as a carrier gas and 20 sccm of C2H2 as a feedstock at 95 torr and 750 °C. We studied the growth behavior of CNTs by varying the annealing time of the substrate between 0 and 420 sec. As-grown CNTs were characterized by using field emission scanning electron microscopy, high resolution transmission electron microscopy, Raman spectroscopy, and atomic force microscopy. The 90~300 sec of annealing gave rise to the growth of vertically aligned DWCNTs with the height of ~700 μm for 10 min while the annealing below 60 sec and over 420 sec caused the vertical growth of 300~700-μm-thick MWCNTs for 10 min. Several radial breathing mode (RBM) peaks in the Raman spectra were observed at the Raman shifts of 112~191 cm-1, indicating the presence of DWCNTs with the tube diameters 3.2~3.4 nm. The low G/D peak intensity ratios were observed to imply the low defect density of the as-grown DWCNTs. |
| 저자 |
Ko Jae Sung, In Sung Choi, Naesung Lee
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| 소속 |
세종대 |
| 키워드 |
double-walled carbon nanotube (DWCNT); thermal chemical vapor deposition (CVD); catalyst annealing time; radial breathing mode (RBM)
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| E-Mail |
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