▎ 摘　　要

A 3D hierarchical porous graphene-like carbon (3D HPG) has been studied as conducting support for Pd and Mn3O4 nanoparticles. The Pd-Mn3O4 supported on 3D HPG demonstrates as an excellent catalyst for oxygen evolution reaction (OER) in alkaline medium. The Pd-Mn3O4(wt 2:1)/HPG catalyst shows a low onset potential of 0.497 V and achieves a high current density of 5.3 mA cm(-2) at 0.7 V (vs. SCE). The outstanding electrocatalytic activity is attributed to a synergistic effect between Pd and Mn3O4, and the 3D HPG enhances conductivity for charge transport and gives more active sites for the OER reaction.