氮掺杂还原氧化石墨烯负载铂催化剂的制备及甲醇电氧化性能

摘要

Nitrogen-doped reduced graphene oxide materials (N-RGO) derived from pyrolysis of graphene oxide (GO)/polyaniline composites were used as a support for the immobilization of Pt nanoparticles. The morphologies and structures of N-RGO and Pt/N-RGO were comprehensively characterized by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and Raman spectroscopy. The electrocatalytic activities of the as-prepared catalysts for CO stripping and methanol oxidation were investigated by cyclic voltammetry and chronoamperometry. The results showed that GO was reduced to multilayer graphene by thermal annealing accompanied with successful incorporation of N atoms into RGO. Moreover, the presence of the doped N atoms enhanced the surface defects and electrical conductivity of the RGO materials. Pt nanoparticles on N-RGO were more evenly dispersed, had better CO tolerance, and had higher activity/stability for methanol oxidation than those on RGO without N doping.%采用高温热解聚苯胺修饰的氧化石墨烯(PANI-GO)，得到了氮掺杂的还原氧化石墨烯碳材料(N-RGO)，以其负载Pt制备了Pt/N-RGO纳米结构电催化剂。采用透射电镜(TEM)、X射线光电子能谱(XPS)、X射线衍射(XRD)谱及拉曼光谱等技术对N-RGO和Pt/N-RGO的形貌及结构进行了表征，用循环伏安、计时电流等电化学技术研究了Pt/N-RGO电极催化剂对CO溶出反应和甲醇电氧化反应的催化性能。结果表明：高温热解PANI-GO可同时实现GO的还原及其氮掺杂的过程，氮掺杂引起还原氧化石墨烯碳材料表面缺陷结构和导电性的增加；与相应的未掺杂氮样品Pt/RGO相比较， Pt/N-RGO样品上Pt颗粒的分散更均匀，显示出更强的抗CO毒化能力和更高的甲醇电氧化催化活性及稳定性。