A sandwich-like Ga2FeS4-supported single metal atom as a promising bifunctional electrocatalyst for overall water splitting

Abstract

Developing highly efficient and economical bifunctional catalysts for overall water splitting is challenging but a great concern for the renewable energy conversion and applied catalysis towards a sustainable development. Herein, by employing first principles calculations, the catalytic performance of various transition metal (TM) atoms supported on single-layer ternary Ga₂FeS₄ for water splitting has been systematically investigated. Strikingly, it was evidenced that the sandwich Ga₂FeS₄ can form a tunable interfacial polarization field under external strain, which can effectively regulate its catalytic performance. Specifically, Au-Ga₂FeS₄ under a 0.5% tensile strain presents good bifunctional catalytic performance, with the low overpotentials of 0.03 and 0.48 eV, respectively, for the HER and OER, outperforming the experimentally identified Pt and IrO₂. Considering the massive possibilities of these ternary substrates and the easily accessible characteristic of external strain, the findings highlighted here can provide a useful theoretical guideline for designing efficient bifunctional SACs in overall water splitting.