Heterostructure and phase engineering synergistically activated highly efficient alkaline hydrogen evolution in Mo2C/MoS2-rGO hybrids

Heterostructure and phase engineering are effective method to tune the electronic structure of MoS 2 , which can activate and boost its intrinsic catalytic activity. Herein, the theoretical calculations reveal that the free energy of H∗ adsorption (ΔG H∗ ) for Mo 2 C (−0.65 eV) is lower than MoS 2 (2.05 eV), which is favorable for hydrogen adsorption. Inspired by the theoretical predictions, we develop a facile strategy to prepare nanostructured Mo 2 C/MoS 2 dispersed on reduced graphene oxide (rGO) via a hydrothermal preparation and carburization reaction. Since the Mo 2 C/MoS 2 -rGO nanostructures with great deal of both MoS 2 and Mo 2 C edges by heterostructure and phase engineering, which can induce massive active sites for HER on the surface of rGO, the intimate interfacial coupling effect between Mo 2 C and MoS 2 can effectively improve the charge transfer rate. The Mo 2 C/MoS 2 -rGO catalyst exhibits exceptional HER properties, delivering a high turnover frequency (TOF) of 0.209 s −1  at an overpotential of 200 mV in 0.1 M KOH. This work may open a new window for designing NPM electrocatalysts with highly efficient HER property based on earth-abundant materials.