▎ 摘　　要

Graphene is an attractive catalyst support for direct methanol fuel cells (DMFCs). However, the close-packed structure and hydrophobicity of the graphene sheets will prevent noble metal nanoparticles (NMNPs) from exposed to the electrolyte, leading to a reduction in the utilization of NMNPs. In this work, a unique 3D graphene/PtNPs composite catalyst with double network channels is in-situ fabricated. The superficial rGO sheets of PS/rGO@PtNPs composite particles are interconnected to form 3D network structure due to the supporting of the PS microspheres. The 3D structure not only provides interconnected channel for diffusion of the electrolyte into the composite catalysts, but also forms an ideal graphene network to increase the connectivity and conductivity of the composite catalysts. Compared with the close-packed rGO/PtNPs catalyst, the PS/rGO@PtNPs composites with 3D network structure have higher catalytic activity, reaches up to 586.96 mA/mg for methanol oxidation reaction. (C) 2016 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.