Novel electrocatalyst with abundant oxygen vacancies enabling efficient two-electron water oxidation reaction for H2O2 synthesis

Abstract

In the realm of electrocatalytic two-electron water oxidation reaction, the quest for efficient and selective catalysts poses a significant challenge in balancing productivity and activity, hindering the decentralized generation of hydrogen peroxide (H2O2) through electrochemical means. Addressing this hurdle, our study introduces a novel approach to crafting an effective and stable electrocatalyst for the two-electron water oxidation reaction (2e-WOR). Through the synthesis of magnesium stannite tungstate from a mixture of MgSnO3 and WO3, the engineer of a material with abundant oxygen vacancies is crucial for catalytic activity. This catalyst demonstrates exceptional performance, ascribed to its distinctive oxygen vacancies proximal to the active center Sn and electronic modulation by tungsten. Notably, Mg1-xSnWO6-x700 exhibits a remarkably low overpotential of 70 mV at 10 mA cm−2, coupled with a high faradic efficiency of 84 % for 2e- WOR at 2.6 V vs. RHE, maintaining consistent performance over 35 h. Furthermore, the formation of oxygen vacancies and the associated electronic transfer underscore the novelty and promise of our material in advancing the field of two-electron WOR. In sum, our electrocatalyst presents a cost-efficient and selective solution for water oxidation, offering potential avenues for enhancing H2O2 production.