Iron molybdenum selenide supported on reduced graphene oxide as an efficient hydrogen electrocatalyst in acidic and alkaline media.

It is of great significance to develop inexpensive and high-efficiency electrocatalysts for the hydrogen evolution reaction (HER). In this work, we synthesized iron molybdenum selenide (FeSe-MoSe) loaded on reduced graphene oxide (FeSe-MoSe/rGO) by a one-step hydrothermal method. We further optimized the Fe/Mo ratio and determined the best ratio to be 1-1. In acidic (or alkaline) solution, the optimized FeSe-MoSe(1-1)/rGO has a small Tafel slope of 55 (or 80) mV dec and needs an overpotential of 101 (or 178) mV to achieve 10 mA cm. These good properties are mainly due to the structure of bimetallic selenides combining rGO. Moreover, rGO enhances the electrical conductivity. Furthermore, the synergistic effect between FeSe-MoSe(1-1) and rGO results in better HER performance. Density functional theory (DFT) calculation proves that FeSe-MoSe(1-1)/rGO has a small work function. Based on our reasonable design and analysis, FeSe-MoSe(1-1)/rGO is expected to be an efficient and robust catalyst for large-scale applications.