Cobalt atoms anchored on nitrogen-doped hollow carbon spheres for efficient electrocatalysis of oxygen reduction to H2O2

Abstract

Electrochemical production of hydrogen peroxide (H2O2) from oxygen reduction reaction (ORR) is a promising alternative to the costly anthraquinone method. However, the sluggish kinetics of ORR on most electrocatalysts restricts its wide application. Therefore, exploring electrocatalysts with high activity and selectivity for two–electron ORR is significant. Herein, cobalt atoms anchored on nitrogen-doped hollow carbon spheres (Co–NHCS) are presented for H2O2 electrosynthesis. The Co–NHCS catalyst exhibits excellent H2O2 electrosynthesis performance in acidic media with high reactivity with an ORR potential of 0.581 V at 1.0 mA cm−2 and H2O2 selectivity up to 90%. Moreover, the H2O2 output in the assembled device reaches 2980 mg l−1 h−1 with high Faraday efficiency. The enhanced performance of Co–NHCS originates from the hollow structure and center sites of Co introduction. This work affords a facile strategy for the fabrication of high-efficient carbon-based materials for H2O2 electrosynthesis.