Engineering the Local Atomic Environments of Indium Single-Atom Catalysts for Efficient Electrochemical Production of Hydrogen Peroxide

The in-depth understanding of local atomic environment-property relationships of p-block metal single-atom catalysts toward the 2 e(-) oxygen reduction reaction (ORR) has rarely been reported. Here, guided by first-principles calculations, we develop a heteroatom-modified In-based metal-organic framework-assisted approach to accurately synthesize an optimal catalyst, in which single In atoms are anchored by combined N,S-dual first coordination and B second coordination supported by the hollow carbon rods (In SAs/NSBC). The In SAs/NSBC catalyst exhibits a high H2O2 selectivity of above 95 % in a wide range of pH. Furthermore, the In SAs/NSBC-modified natural air diffusion electrode exhibits an unprecedented production rate of 6.49 mol peroxide g(catalyst)(-1) h(-1) in 0.1 M KOH electrolyte and 6.71 mol peroxide g(catalyst)(-1) h(-1) in 0.1 M PBS electrolyte. This strategy enables the design of next-generation high-performance single-atom materials, and provides practical guidance for H2O2 electrosynthesis.

Automated summary

Rarely reported is the in-depth understanding of local atomic environment-property relationships of p-block metal single-atom catalysts towards the 2e(-) oxygen reduction reaction (ORR). In this study, a heteroatom-modified In-based metal-organic framework-assisted approach is developed to synthesize an optimal catalyst, In SAs/NSBC, with accurately anchored single In atoms supported by hollow carbon rods. The catalyst exhibits a high H2O2 selectivity and unprecedented production rates in different electrolytes, providing practical guidance for H2O2 electrosynthesis and enabling the design of high-performance single-atom materials.