Minimizing H2O2 Loss in Industrial Electrosynthesis via Asymmetric Main-Group Sn Single-Atom Catalysts

Abstract

The electrosynthesis of hydrogen peroxide (H₂O₂) via the two-electron oxygen reduction reaction offers an appealing and sustainable route for on-site H₂O₂ production. However, its broader applicability is constrained by subpar yields, primarily resulting from insufficient selectivity and the occurrence of electrochemical and/or chemical decomposition of H₂O₂. Herein, we demonstrate that asymmetric N/S co-coordinated main-group Sn sites can effectively stabilize oxygen intermediates and rapidly desorb the generated H₂O₂, thereby enhancing 2e^- ORR pathway selectivity while suppressing undesirable H₂O₂ decomposition reactions. At an industrially relevant current density of 300 mA cm^-2, the main-group catalyst achieves an exceptional H₂O₂ faradaic efficiency of 93%. When scaled to an industrial sized area of 100 cm², the pilot reactor delivers an impressive H₂O₂ production rate of 353.5 mmol h^-1 at 20 A. In situ characterizations and theoretical simulations reveal that the main-group Sn sites exhibit inertness toward activation of H₂O₂, thereby mitigating H₂O₂ loss in electrosynthesis. The asymmetric N/S-coordination enhances electron transfer between the Sn center and oxygen intermediates, stabilizing the *OOH intermediate and facilitating H₂O₂ generation. This work presents a promising strategy for minimizing H₂O₂ loss in electrochemical production via the rational design of main-group catalysts with well-defined coordination and electronic structures.

Keywords: Asymmetric coordination; H2O2 decomposition; H2O2 electrosynthesis; Industrial‐level current; Main‐group catalysts.