▎ 摘　　要

Polystyrene (PS) microspheres are wrapped by reduced graphene oxide (rGO) nanosheets based on the thermodynamically driven heterocoagulation method, and in order to acquire PS/rGO@PtRuNPs composite particles, the resultant PS/rGO composite particles should be used as matrix to deposit Pt-Ru alloyed nanoparticles (PtRuNPs), taking unique advantages of both alloying effect and the 3D structure. A distinct 3D graphene/PtRu alloyed composite catalyst is fabricated by in-situ stacking of the ternary composite particles, which has double network channels for both electrons and reaction solution. The rGO sheets on the surface of the PS microspheres are interconnected interrelated with each other to construct a 3D network structure, while a interconnected gap among the spherical composite particles forms the other network for the reaction solution to spread into the composite catalyst. The influence of different Pt/Ru ratio on the catalytic activity for methanol oxidation is investigated, and under the obtained optimal Pt/Ru ratio, the most effective and economical noble metal consumption is further explored through changing the ratio of metal to graphene. As a result, the PS/rGO@PtRuNPs ternary composite catalyst has better catalytic activity than close-stacked rGO/PtRuNPs catalyst.