Selective and durable H₂O₂ electrosynthesis catalyst in acid by selenization induced straining and phasing.

Abstract

Developing efficient electrocatalysts for acidic electrosynthesis of hydrogen peroxide (H₂O₂) holds considerable significance, while the selectivity and stability of most materials are compromised under acidic conditions. Herein, we demonstrate that constructing amorphous platinum-selenium (Pt-Se) shells on crystalline Pt cores can manipulate the oxygen reduction reaction (ORR) pathway to efficiently catalyze the electrosynthesis of H₂O₂ in acids. The Se₂‒Pt nanoparticles, with optimized shell thickness, exhibit over 95% selectivity for H₂O₂ production, while suppressing its decomposition. In flow cell reactor, Se₂‒Pt nanoparticles maintain current density of 250 mA cm^-2 for 400 h, yielding a H₂O₂ concentration of 113.2 g L^-1 with productivity of 4160.3 mmol g_cat^-1 h^-1 for effective organic dye degradation. The constructed amorphous Pt-Se shell leads to desirable O₂ adsorption mode for increased selectivity and induces strain for optimized OOH* binding, accelerating the reaction kinetics. This selenization approach is generalizable to other noble metals for tuning 2e^‒ ORR pathway.