Superaerophobic WC-Mo<sub>2</sub>C Ceramic Electrode with MoWC<sub>2</sub>/Mo<sub>2</sub>C Heterostructure for Hydrogen Evolution Reaction at High Current Density
Anding Huang, Haisen Huang, Sishi Huang, Chuntian Tan, Yang Yang, Jiahao Li, Luyuan Hao, Feihong Wang, Xin Xu, Simeon Agathopoulos
Abstract
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 % Mo 2 C, with a structure of an oriented asymmetric finger-like hole. Its high catalytic activity was experimentally confirmed, attributed to the in situ MoWC 2 /Mo 2 C 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 H 2 SO 4 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 MoWC 2 /Mo 2 C heterostructure could regulate the electronic structure, with appropriate hydrogen adsorption energy in acidic media and minimal water dissociation potential in alkaline media.