State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science & Technology of China, Chengdu 610054, PR China.
J Colloid Interface Sci. 2012 May 15;374(1):34-9. doi: 10.1016/j.jcis.2012.02.005. Epub 2012 Feb 10.
Iron catalyst films for the growth of carbon nanotube (CNT) arrays are prepared using sol-gel technique during different hydrolytic periods. It is shown that the extent of hydrolysis of the catalyst precursor has strong impacts on the size and density of iron catalyst particles, which distributed on surface of the film. The iron catalysts formed big clusters in the early stage of the hydrolysis, whereas the particle size decreased dramatically to approximate 20 nm when the hydrolytic duration is as long as 150 h. The reaction between the hydrolytic product of ethyl orthosilicate and the iron oxide particles effectively influence the structure of catalysts during the process of annealing precursor films and reducing the iron oxide particles into iron catalysts. We believe that the hydrolytic product limits the mobility of the catalyst particles, preventing them from aggregating into big clusters by Ostwald ripening. This catalyst film may be utilized to create a template to control the length and quality of CNTs.
采用溶胶-凝胶技术在不同水解期制备用于生长碳纳米管（CNT）阵列的铁催化剂薄膜。结果表明，催化剂前体的水解程度对分布在薄膜表面上的铁催化剂颗粒的大小和密度有强烈的影响。在水解的早期阶段，铁催化剂形成了大的团簇，而当水解时间长达 150 小时时，颗粒尺寸急剧减小到近似 20nm。正硅酸乙酯的水解产物与氧化铁颗粒之间的反应在退火前体膜和将氧化铁颗粒还原为铁催化剂的过程中有效地影响了催化剂的结构。我们相信，水解产物限制了催化剂颗粒的迁移性，通过奥斯特瓦尔德熟化防止它们聚集成大的团簇。这种催化剂薄膜可用于创建一个模板来控制 CNT 的长度和质量。
