Electrosynthesis of HO Promoted by π-π Interaction on a Metal-Free Carbon Catalyst.

The synthesis of hydrogen peroxide (HO) through electrocatalytic oxygen reduction reaction is an ideal alternative to the current energy-intensive anthraquinone process, but developing cost-effective and high-efficiency electrocatalysts is still challenging. Herein, a metal-free graphitic carbon nitride/carbon nanotube (g-CN/CNT) hybrid catalyst can enhance HO production via π-π interaction is reported, achieving almost unity (97%) HO production at 0.57 V with high selectivity of over 92% across the wide potential range from 0.6 to 0 V. Other carbon materials with weak interaction with g-CN, such as acetylene black and super P, show markedly weakened HO production, indicating the importance of π-π interaction. Electron transfer kinetic analysis combined with density functional theory calculations indicates that the synergistic effect between g-CN and CNT enhances electron transfer and O activation between g-CN and CNT, leading to enhanced HO production performance. This work provides a complementary approach for HO production from oxygen reduction besides introducing oxygenated groups or heteroatom doping into carbon materials.