Three-dimensional reduced graphene oxide-Mn3O4 nanosheet hybrid decorated with palladium nanoparticles for highly efficient hydrogen evolution

A three-dimensional (3D) reduced graphene oxide-Mn3O4 nanosheet (Mn3O4@rGO) hybrid was achieved by simple electrodeposition technique. Small palladium nanoparticle were homogeneously anchored onto Mn3O4@rGO substrate through the reduction of palladium salt. The interpenetrating network architecture of Mn3O4@rGO greatly inhibited the aggregation of 2D sheets of Mn3O4 and rGO, and the open 3D orientation of the Mn3O4@rGO hybrid nanosheets on the electrode facilitated both mass transport and electron transfer as well as maximally exposed active sites. The introduction of Mn3O4 enhanced the structural and electrochemical stability of rGO. The as-synthesized Pd/Mn3O4@rGO hybrid was employed as an electrocatalyst for electrocatalytic hydrogen evolution reaction (HER). The electrocatalyst showed a low overpotential of 20 mV at 10 mA cm−2, a small Tafel slope of 48.2 mV dec−1, and a large exchange current density of 0.59 mA cm−2. Importantly, the catalyst possessed superior durability with 85.87% of catalytic activity after a long-time test (10 h). This work presents a simple and efficient stratagy to construct high-performance electrocatalysts for energy and environmental applications.