三维石墨烯负载PtRu合金纳米粒子对甲醇氧化的电催化性能

摘要

以乙二醇为溶剂和还原剂、聚乙烯吡咯烷酮（PVP）为络合剂，采用有机溶胶法并结合冷冻干燥，制备了三维石墨烯负载PtRu合金纳米粒子（PtRu／Gr）催化剂．采用SEM，TEM和XRD对催化剂的形貌、组成、粒径大小和相结构进行表征，采用循环伏安法和计时电流评价催化剂对甲醇氧化的催化活性，并与自制Pt／Gr和Pt／C进行对比．结果表明，平均粒径约2．1 nm的PtRu合金粒子均匀分散在三维石墨烯表面，其对甲醇氧化催化活性分别是Pt／Gr和Pt／C催化剂的1．5倍和2．6倍，而且具有高的稳定性和抗中毒能力．%PtRu alloy nanoparticles supported on 3D graphene (PtRu/Gr)were synthesized via organic sol method combined with freeze drying by using ethylene glycol as solvent and reducing agent,polyvinylpyrroli-done (PVP)as complexing agent.The morphology,composition,particle size,and phase structure were charac-terized by SEM,TEM,and XRD.The catalytic activities of PtRu/Gr toward methanol oxidation were evaluated by means of cyclic voltammetry and chronoamperometry and compared with those of self-made Pt/Gr and Pt/C catalysts.The results showed that highly dispersed PtRu alloy nanoparticles with average sizes of ca.2.1 nm are dispersed on the surfaces of 3D graphene,and its activity toward methanol oxidation is 1 .5 and 2.6 times as high as that of Pt/Gr and Pt/C,respectively.Furthermore PtRu/Gr has high stability and poisoning tolerance to the intermediates in methanol oxidation.