Rationally Modulating the Functions of Ni3Sn2-NiSnOx Nanocomposite Electrocatalysts towards Enhanced Hydrogen Evolution Reaction

Identifying electrocatalysts with functions of easy dissociation of water, rapid transformation of hydroxyl and facile hydrogen-hydrogen bond formation are indispensable while challenge for realizing efficient alkaline hydrogen evolution reaction (HER). Herein, we presented the design of Ni3Sn2-NiSnOx nanocomposites towards addressing this challenge. We showed that Ni3Sn2 possessed ideal hydrogen adsorption and low hydroxyl adsorption abilities and NiSnOx facilitated water dissociation and hydroxyl transfer process, respectively. Consequently, the fine-tuned interplay of the two functional parts realized the mutual coordination among the multiple functions and led to significantly boosted HER kinetics. Current densities of 10 and 1000 mA cm(-2) were obtained at overpotentials of 14 and 165 mV on the optimized catalyst. This work highlights the significance of considering intrinsic interactions between active sites and all pertinent intermediates on obtaining promising electrocatalysts.