SnSe nanosheets with Sn vacancies catalyse H2O2 production from water and oxygen at ambient conditions

Abstract

Hydrogen peroxide (H₂O₂) is a vital industrial chemical and sustainable energy carrier. However, achieving a simple, efficient and cost-effective synthesis under mild conditions remains an important challenge. Here we show that SnSe nanosheets with Sn vacancies can directly catalyse H₂O₂ production from H₂O and O₂ under ambient conditions, without additional energy inputs (for example, light and electricity), cocatalysts or sacrificial reagents. This approach achieves an optimal H₂O₂ production rate of ~2.6 mmol g⁻¹ h⁻¹ at 40 °C and maintains long-term stable production (~0.3 mmol l⁻¹) in a continuous-flow reactor for over 50 h at room temperature. Experimental and theoretical analyses reveal that this unique thermocatalytic effect arises from a dynamic process involving Sn vacancy defect-induced sequential dissociation of H₂O and activation of O₂ molecules, along with reversible surface restructuring of the SnSe nanosheets to release H₂O₂. Our findings offer a notably simple, highly efficient and entirely green strategy for H₂O₂ production, with broader implications in other catalytic reactions involving water activation.