LAUSR

Abstract Developing cost-efficient bi-functional catalysts with high performance for electrochemical water splitting is of paramount significance but a challenge for the future energy scenario. Hetero-structure engineering has invoked new feasibilities to achieve comprehensive promotion for both activity and durability. However, there is still a grand challenge to develop a facile strategy for hetero-structure construction. Herein, V-Ni3S2@NiOOH core-shell hetero-structure has been fabricated via a facile electrochemical anodization. It is demonstrated that this core-shell heterostructure featured with a thin but disordered NiOOH shell exhibits optimized structure and facilitated charge transfer resulting in a modulated catalytic activity as well as a structural stability. As expected, it is observed that the overpotential of V-Ni3S2@NiOOH for HER shows 45 mV lower than that of Pt/C catalysts at 250 mA cm-2. The OER activity of V-Ni3S2@NiOOH is comparable with that of RuO2 as well. This superior performance for both HER and OER indicates the potential of V-Ni3S2@NiOOH to be an alternative to noble-metal-based catalysts for electrochemical water splitting. Our findings in this work may put forward a fresh concept and strategy to construct hetero-structure for many other high-performance energy materials using in the next-generation energy conversion and storage devices.