Harnessing selective and durable electrosynthesis of H2O2 over dual-defective yolk-shell carbon nanosphere toward on-site pollutant degradation

Electrocatalytic 2e- oxygen reduction reaction (ORR) strategy for decentralized and on-demand production of H2O2 has emerges as an appealing alternative to prevailing anthraquinone process. Nevertheless, the sustainable development of high-performance and low-cost electrocatalysts with high selectivity and durability remains elusive. Herein, we report a metal-free electrocatalyst affording B/N co-doped yolk-shell carbon nanosphere with oxygen-vacancy-decorated graphene armor (B/N-HCNS@VO-G) toward promoted 2e- ORR in alkaline media. Such a dual-defective electrocatalyst harvests excellent H2O2 electrosynthesis performance with a high selectivity of 91 % and a stable operation of 24 h, which is markedly superior to its counterparts and compares favorably with the state-of-the-arts. Density functional theory calculations further reveal the essential roles of defective graphene coating played in advancing the 2e- ORR selectivity of B/N-HCNS@VO-G. More impressively, thusproduced H2O2 (realizing a high yield of 56 ppm at 0.7 V) satisfies an in-situ antibiotic and dye degradation, holding practical promise for on-site wastewater remediation.

Automated summary

A metal-free electrocatalyst has been developed for efficient and selective production of H2O2, showing promise for practical applications in wastewater treatment.