Effect of single atom defect on the multifunctional HER, OER, and ORR electrocatalytic properties of Ga2XY structures: First principles study

Faced with the challenges of energy depletion and environmental pollution, HER/OER/ORR as the main reactions of the water splitting, fuel cells, and metal-air batteries have garnered a lot of attention. In this paper, the Ga 2 XY (X, Y O, S, Se, Te, X≠Y) structure containing single-atom defect is systematically investigated based on the first principles calculation , and its catalytic and electronic properties are also analyzed in depth. The results demonstrated that the catalytic performance is substantially improved by introducing single-atom defect, the Ga 2 OS, Ga 2 OSe, and Ga 2 SeTe defect structures have more excellent performance. Among all the defect structures , the Ga 2 SeTe structure containing Ga atom defect on the Y-side and adsorbed on Y-side Ga atoms (Ga 2 SeTe- V G a Y -Ga Y ) has excellent HER , OER , and ORR performances, the overpotentials is 0.20 eV, 0.30 eV, and 0.51 eV, respectively. The origin of the catalytic activity is also described using crystal orbital Hamilton population (COHP) and charge density calculations. It is shown that the p-orbitals of O and the s-orbitals of Ga undergo significant hybridization, which affects the Ga 2 XY defect structure from the structural level. Our work broadens the research scope in the field of multifunctional catalysis and offers novel approaches to the study of multifunctional catalysts. • Studied the HER/OER/ORR electrocatalytic properties of Ga 2 XY defect structures. • The introduction of single atom enhances the electrocatalytic performance. • Intermediates are more likely to attach to Ga atoms. • The Ga 2 SeTe- V G a Y defect structure showed the best HER/OER/ORR catalytic properties.