利用电沉积Ni纳米晶制备无缠绕阵列碳纳米管  

Synthesis of well-aligned non-tangled carbon nanotubes on a pulse electro-deposited Ni nanocrystalline substrate

作　　者：鲍桥梁[1] 冉祥[1] 张晗[1] 祁祥[1] 傅强[1] 潘春旭[1] 

机构地区：[1]武汉大学物理科学与技术学院,武汉430072

出　　处：《新型炭材料》2008年第1期44-50,共7页New Carbon Materials

基　　金：全国优秀博士学位论文作者专项资金资助项目(200233);高等学校博士学科点专项科研基金资助课题(20070486016)~~

摘　　要：以金属Cu基板上脉冲电沉积Ni纳米晶薄膜作为催化剂,在乙醇火焰中制备了直立、无缠绕阵列碳纳米管。利用原子力显微镜(AFM)、扫描电子显微镜(SEM)、透射电镜(TEM)和激光拉曼谱仪(Raman)对不同工艺制备的Ni纳米晶薄膜和阵列碳纳米管的形貌进行了表征。结果表明:通过综合控制脉冲电沉积参数、电沉积时间和火焰中的合成时间,可以获得大面积、密集、均匀、直立、无缠绕、形态良好、重复性高的阵列碳纳米管。脉冲电沉积Ni纳米晶和合成无缠绕阵列碳纳米管的最佳工艺条件是:脉冲电沉积正、负脉冲的工作频率为154Hz、占空比为38.5%、电沉积时间为1min、基板预热至600℃、火焰中停留1min。通过对生长机理的研究发现:当电沉积时间较短时,获得的Ni纳米晶薄膜较薄,具有较高的局域粗糙程度和催化活性,有利于碳纳米管的同时大面积"拥挤生长"形成阵列结构;另外,通过调整脉冲电沉积参数,可以控制Ni纳米晶的大小,从而控制碳纳米管的长径比,当长径比较小时即可获得无缠绕的阵列碳纳米管。Well-aligned non-tangled carbon nanotubes （CNTs） were grown in ethanol flames on a nanocry-stalline Ni layer that was electro-deposited on a Cu alloy substrate using periodic reverse pulse plating. The morphologies and microstructures of the nanocrystalline layers and the CNTs were characterized by XRD, SEM, TEM, AFM and laser Raman spectroscopy. It was found that a large area of vertically aligned CNTs with uniform density could be produced with high repeatability by controlling the thickness of the Ni nanocrystalline layer and time in the flame. A low electro-deposition time was favorable for the formation of thin layer nanocrystalline Ni with high local roughness and high catalytic activity on which well-aligned CNTs were generated with overcrowded growth that prevented them from becoming tangled. A low aspect ratio of CNTs was needed to keep them from tangling, and this could be adjusted by controlling the pulse electro-deposition parameters to form the desired catalyst particles. The best CNTs can be produced by passing ethanol through a nanocrystalline Ni layer supported substrate at 600 ℃ for 1 min that had been electro-deposited at an output pulse frequency of 154 Hz with duty cycle of 38.5% for 1 min.

关 键 词：脉冲电沉积 纳米晶 碳纳米管 

分 类 号：TB383.1[一般工业技术—材料科学与工程]