Dipole Moment and Polarization Field Induced by Oxygen Vacancies Boosting Piezocatalytic Hydrogen Peroxide Production of Centrosymmetric Material.

Abstract

Piezocatalysis is a sustainable and promising strategy for H₂O₂ synthesis; however, its efficiency is limited by sluggish interfacial charge-transfer kinetics and insufficient active sites. Herein, an oxygen vacancy-rich SnO (SnO-OVs) piezocatalyst was designed with abundant active sites, enhanced dipole moments, and intensified polarization fields, which collectively boost the piezocatalytic H₂O₂ production efficiency. The SnO-OVs achieve an exceptional production rate of 512.29 μmol g^-1 h^-1 in pure water without any sacrificial agents. Mechanistic studies reveal that under compressive strain, SnO-OVs exhibit superior water adsorption capacity and a reduced energy barrier for *OH intermediate formation, synergistically promoting the two-electron water oxidation pathway (2e^- WOR) for H₂O₂ synthesis. Additionally, H₂O₂ preferentially dissociates into *OH rather than forming *O and *H₂O under compressive strain, resulting in effective piezocatalytic BPA degradation via radical-dominated •OH oxidation pathways. This work introduces a novel strategy for efficient H₂O₂ synthesis and facilitates the advancement of sustainable water purification technologies.