A silver catalyst activated by stacking faults for the hydrogen evolution reaction

Finding highly active and low-cost catalysts is a crucial endeavour to harvest clean hydrogen via electrochemical water splitting. Currently, the best catalyst for the hydrogen evolution reaction is based on metallic platinum whose high price severely restricts large-scale application. Here we report a silver catalyst with superior activity and durability in an acid medium that outperforms commercial platinum on carbon, especially under high applied voltages. We adopt a physical technique—laser ablation in liquid—to generate a high density of stacking faults in silver nanoparticles. We find that the stacking faults can cause a low coordination number and high tensile strain, which jointly improve the adsorption energy and transform the non-active silver into a highly active catalyst. In light of the high activity, conductivity, durability and low price, the silver catalyst can serve as a promising alternative to commercial platinum on carbon for industrial application. To achieve large-scale application of water electrolysers we need to find optimal cathode and anode catalysts. This work reports an engineered silver catalyst with high density of stacking faults that exhibits high activity and stability for the hydrogen evolution reaction, outperforming commercial platinum on carbon.