Superaerophobic WC-Mo₂C Ceramic Electrode with MoWC₂/Mo₂C Heterostructure for Hydrogen Evolution Reaction at High Current Density

The production of highly efficient, stable, robust, and low-cost electrodes for the hydrogen evolution reaction (HER) is crucially important in renewable energy technologies. This article presents the production of a porous composite ceramic with a formula of 80 wt % WC–20 wt % Mo2C, with a structure of an oriented asymmetric finger-like hole. Its high catalytic activity was experimentally confirmed, attributed to the in situ MoWC2/Mo2C heterostructure during sintering. What’s more, the produced electrode exhibits both high aerophobicity and high hydrophilicity. The overpotentials of the electrode of 1500 mA·cm–2 in 0.5 M H2SO4 and 1.0 M KOH were 352 and 276 mV, respectively, better than those of the Pt-wire electrode. The chronopotentiometry curves of 10–1500 mA·cm–2 confirmed its long-term stability. Density functional theory (DFT) calculations suggested that the MoWC2/Mo2C heterostructure could regulate the electronic structure, with appropriate hydrogen adsorption energy in acidic media and minimal water dissociation potential in alkaline media.