采用表面修饰技术将碳纳米管(CNT)表面羧基化,通过羧基将钨离子基团修饰到碳纳米管的外表面,再通过高温焙烧处理将钨离子基团氧化成WO3,成功合成了纳米WO3/CNT复合物,进一步还原Pt的前驱体而得到Pt-WO3/CNT复合催化剂.采用X射线粉末衍射(XRD)和透射电镜(TEM)对样品的形貌和晶型结构进行了表征,结果表明,Pt纳米粒子为面心立方晶体结构,均匀地分布在WO3修饰的碳纳米管表面.采用循环伏安(CV)和计时电流法研究了在酸性溶液中Pt-WO3/CNT催化剂对甲醇的电催化氧化活性,结果表明WO3修饰的碳纳米管载铂催化剂比用混酸处理的碳纳米管载铂催化剂对甲醇呈现出更高的电催化氧化活性和更好的稳定性.
Nano-WO3-modified carbon nanotube supported Pt nanoparticles (Pt-WO3/CNT) with uniform dimensions were prepared by adsorption and decomposition of ammonium meta-tungstate (AMT) on the surface of CNTs pretreated with HNO3, and H2PtCl6 as the Pt precursor. The samples were characterized by X-ray powder diffraction (XRD) and transmission electron microscopy (TEM). The Pt nanoparticles had a face-centered cubic crystal structure, and were well dispersed on the external walls and ports of the WO3 CNTs. The electrocatalytic activity of the samples towards the oxidation of methanol was investigated using cyclic voltammetry and chronoamperometry. The results indicated that the Pt-WO3/CNT catalysts exhibited higher electrocatalytic activity, better anti-poisoning ability, and good stability during methanol oxidation compared with Pt/CNTs used for acid oxidation treatments.