In situ coupled MoO3 with CoP/rGO to construct three-dimensional self-supported catalyst for highly efficient alkaline hydrogen evolution reaction

In order to solve the crisis of energy depletion and protect the beautiful natural environment, the development of efficient, cost-effective and stable hydrogen evolution reaction (HER) electrocatalyst has attracted great attention, but it is still an urgent challenge to fabricate an abundant and low cost electrocatalyst. In this article, a novel HER catalyst with heterogeneous structure interfaces was in situ synthesized by multi-step electrodeposition method, and the mechanism of the enhancement of its electrocatalytic activity was elucidated by the combination of density functional theory (DFT) calculation and multi-characterizations. The initial overpotential is only 83 mV and the Tafel slope is only 58.5 mV/dec, which is better than most of other reported CoP-based electrocatalyst. At the meantime, DFT calculations show that the incorporation of MoO 3 and rGO leads to electron redistribution among different components, which ensures efficient adsorption and activation of H 2 O molecules and hydrogen atoms. Therefore, this work will contribute to the understanding of the mechanisms associated with heterojunctions and provide guidance for the rational design of a hybrid catalyst.