LAUSR

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.