Low‐Coordinated Mo Clusters for High‐Efficiency Electrocatalytic Hydrogen Peroxide Production

Abstract

Abstract Electrocatalytic oxygen reduction reaction (ORR) to generate hydrogen peroxide (H2O2) via a 2e− pathway offers a green alternative to the energy‐extensive anthraquinone process; however, the challenge lies in the development of low cost and effective 2e− ORR catalysts. In this work, a highly selective and stable Mo clusters supported by nitrogen‐doped carbon polyhedrons catalyst for direct H2O2 electrosynthesis are first designed, which shows a high H2O2 selectivity (>77%) in the applied potential range varying from 0.2 to 0.65 V vs RHE, and an excellent mass activity of 29.0 A gcat.−1 (at 0.65 V) with negligible activity decay over 10 000 cycles in an alkaline medium. Moreover, the catalyst displays a yield rate of 136.2 ± 1.5 ppm cm−2 h−1 at −20 mA cm−2 in a continuous flow cell with neutral electrolyte. Taken together, the obtained performance metrics are comparable to the best‐reported ORR results. Density‐functional theory analyses reveal that Mo clusters can donor electrons to activate O2 molecules and strengthen the *OOH binding on Mo sites as well, thus inducing a high H2O2 selectivity. The present work provides a unique insight into the atomic introduction of metal clusters‐based materials for 2e− ORR to H2O2 powered by renewable energy.

Keywords

• green route
• hydrogen peroxide electrosynthesis
• low‐coordinated
• Mo nanoclusters
• oxygen reduction reaction