Self-Optimized Reconstruction of Metal-Organic Frameworks Introduces Cation Vacancies for Selective Electrosynthesis of Hydrogen Peroxide.

The electrocatalytic synthesis of hydrogen peroxide (HO) through the two-electron oxygen reduction pathway represents a green production process that has gained increasing importance. Nevertheless, there is a dearth of efficacious catalysts to attain high activity under industrial current density. In this study, we present a strategy for cation vacancy generation through metal-organic frameworks self-optimized reconfiguration for the efficient electrosynthesis of HO under industrial current densities in solid-electrolyte cell. The ZIF-ZC91@Co(OH)-V electrocatalyst exhibits significant HO selectivity of 97.8%, and the HO productivity is up to 24.53 mol g  h with a direct and continuous output of ∼3.36 wt% HO aqueous solutions under industrial current density (400 mA cm). Impressively, the ZIF-ZC91@Co(OH)-V possesses superb long-term durability for over 220 h and can output HO aqueous solution with a concentration of ∼8.03 wt% in the pilot experiment. Theoretical calculations confirm that the introduction of modest cation vacancies optimizes the adsorption strength of *OOH intermediate and reduces both thermodynamic and kinetic barriers, thus balancing the selectivity of the two-electron oxygen reduction. This work provides valuable insights into the rapid, eco-friendly synthesis of HO and the rational design of highly active catalysts.