Facile Synthesis of Medium Entropy Sulfides as Hydrogen Evolution Co-Catalysts with CdS for Photocatalytic Water Splitting

In this work we introduce (MoWCoNi)S_x medium entropy sulfide nanoparticles from a facile, bottom-up, low-temperature solvothermal synthesis approach as effective hydrogen evolution reaction (HER) co-catalysts with CdS for visible light driven photocatalytic water splitting. We establish the relationships between composition, structure, amorphicity/crystallinity and catalytic activity in these non-layered, sulfur-deficient medium entropy sulfide nanoparticles. When hybridizing these medium entropy sulfides as HER co-catalysts with CdS we show that their long-term catalytic activity outperforms single-elemental sulfides from a similar synthesis route, which we suggest to possibly be related to sluggish diffusion effects in the medium entropy sulfides.<br/>This work has been funded by European Research Council (ERC) grant HighEntropy2D.