Ni-Mo based metal/oxide heterostructured nanosheets with largely exposed interfacial atoms for overall water-splitting

Interfacial atoms in the heterostructured catalyst are of great importance due to their modulated electronic structure that can trigger enhanced activity in various catalytic processes. Herein, a unique Ni-Mo based metal/oxide heterostructure with abundant mesopores was reported, which enables the interfacial Ni atoms exposed extensively. Atomic-scale structure characterization combined with density functional theory calculation revealed that the interfacial Ni exhibit an enriched charge state, endowing optimized adsorption strength to the intermediates in alkaline hydrogen evolution reaction (HER). As a result, this catalyst recorded an ultralow overpotential of 16 [email protected] mA/cm2, addressing one of the best activities for alkaline HER. Interestingly, this synthetic strategy was extended to synthesize Fe-doped metal/oxide heterostructure that exhibited remarkable oxygen evolution reaction (OER) performance as well. As a proof-of-concept, the prepared catalysts were assembled in an electrolyzer, which delivered exceptional overall water splitting performance and even exceeds the Pt‖RuO2 cell, demonstrating a promising platform for further catalyst design.