金纳米粒子在硫醇修饰多壁碳纳米管表面的吸附

Adhesion of gold nanoparticles on thiol-modified MWCNTs

碳纳米管、金纳米粒子及其复合物具有独特的性质和多种用途而受到广泛关注。以柠檬酸三钠还原氯金酸制备了粒径约为16nm的金胶体，以盐酸纯化处理CVD法生长的多壁碳纳米管粗品，去除残余催化剂和无定型碳，以浓硫酸，硝酸混合液氧化碳纳米管，在碳纳米管表面形成羟基和羧酸根基团，氧化的碳纳米管以3-巯基丙基三甲氧基硅烷处理，使其表面硫醇功能化。表面硫醇化的碳纳米管加入到金胶体中，金纳米粒子通过Au-S键吸附到碳纳米管表面。透射电镜图片显示金纳米粒子分布在碳纳米管表面，金纳米粒子和碳纳米管形成了复合物。

Gold nanoparticles, carbon nanotubes and their composites have been extensively studied for their versatile potential applications due to their unique properties. In this article, colloidal gold was prepared from hydrogen tetrachloroaurate by using Na3-citrate as reducing agent, and gold nanoparticles with size around 16nm were obtained. Raw CVD grown MWCNTs were treated with hydrochloric acid to remove the residual catalysts and amorphous carbon particles, and oxidized in a mixture of concentrated sulfuric acid and nitric acid to form functional groups such as hydroxyl and carboxyl groups on their surfaces. The oxidized MWCNTs were then thiol-modified with （3-mercaptopropyl）-trimethoxysilane. The thiol-modified MWCNTs were added into the gold colloid, and the gold nanoparticles were adhered to the surfaces of the MWCNTs through the Au-S bonding between the gold nanoparticles and the thiol groups. TEM images confirm that the MWCNT/gold nanoparticle composite was formed and that the gold nanoparticles distributed along the walls of the MWCNTs.