Pt-modified molybdenum carbide for the hydrogen evolution reaction: From model surfaces to powder electrocatalysts

This work explores the opportunity to substantially reduce the cost of hydrogen evolution reaction (HER) electrocatalysts by supporting one monolayer (ML) of platinum (Pt) on low-cost molybdenum carbide (Mo2C) substrate. These efforts were primarily directed towards scaling a thin-film catalyst to high surface area particles. Electrochemical experiments investigated single-phase Mo2C thin films modified by different coverages of Pt for the HER. The ML Pt-Mo2C thin film showed Pt-like HER activity while displaying excellent stability under HER conditions. The promising results on thin films were then extended to more practical powder catalysts. Samples of various Pt loadings on Mo2C powders were synthesized using the co-impregnation method and were evaluated for HER activity. The ability to successfully link electrochemical activity on thin films and powder catalysts was thus demonstrated.