催化裂解酚醛树脂在膨胀石墨表面形成碳纳米管研究

Research on Carbon Nanotubes Growth on the Surface of Expanded Graphite by Catalytic Pyrolysis of the Phenolic Resin

为满足钢铁工业对碳复合耐火材料低碳化的要求，发挥膨胀石墨在耐火材料中吸收热应力和碳纳米管增强增韧的协同作用，本工作采用通过在膨胀石墨表面负载催化剂，催化裂解酚醛树脂形成碳纳米管。主要研究了热处理温度、催化剂种类和含量等因素对膨胀石墨表面形成碳纳米管的影响。结果表明：以柠檬酸为络合剂，在膨胀石墨表面分别负载铁、钴、镍的硝酸盐催化剂，800～1100℃均能催化裂解酚醛树脂形成碳纳米管，在900℃氮气气氛下热处理负载2wt％的Ni（NO3）：·6H2O催化剂的膨胀石墨时碳纳米管生长最好；在负载催化剂的膨胀石墨表面形成碳纳米管符合“顶端生长”机制。

In order to meet the requirements of low carbon containing refractories for steel making industry and obtain excellent properties of expanded graphite （EG） and carbon nanotubes （CNTs）, carbon nanotubes were synthesized on the surface of expanded graphite containing catalyst by catalytic pyrolyses of the phenolic resin. In this paper, the firing temperatures, contents and kinds of catalyst were investigated to synthesize CNTs. The results showed that CNTs formed on the surface of EG containing ferric nitrate, cobalt nitrate and nickel nitrate by catalytic pyrolysis of the phenolic resin from 800 to 1100℃. The morphologies of CNTs were the best with 2wt% nickel nitrate as catalyst in nitrogen atmosphere at 900℃. Moreover, the ＂tip growth mechanisms＂ is predominant for the growth of CNTs on the surface of expanded graphite.