Phosphorus doped hierarchical porous carbon: an efficient oxygen reduction electrocatalyst for on-site H2O2 production†
Abstract
The electrochemical oxygen reduction reaction through a two-electron process (2e− ORR) has been considered a promising alternative for on-site hydrogen peroxide (H2O2) production. Nevertheless, exploring low-cost and stable electrocatalysts with higher activity and selectivity remains a great challenge in practical applications. Herein, a novel phosphorus-doped macro/meso/micro-porous carbon (P-MC) electrocatalyst was successfully synthesized using sodium phytate (SP) as the precursor, which can not only change the electronic structure of carbon by P-doping, but also regulate the pore structure of the material with self-decomposition. Therefore, the prepared P-MC possesses excellent electrocatalytic performance and stability for 2e− ORR. When tested in 0.1 M KOH, the P-MC exhibits an outstanding faradaic efficiency (FE%) over 98% (0.3 V–0.5 V vs. RHE) and a higher H2O2 yield of 8.4 mol h−1 gcat.−1, which is 16.8 times higher than that of MC prepared with glucose as a precursor (0.5 mol h−1 gcat.−1). Interestingly, the on-site produced H2O2 can be successfully used for efficient disinfection and water treatment, which can solve the problems of high cost, environmental pollution, and potential risks in current H2O2 industrial production. This study provides a convenient strategy for designing highly active carbon-based electrocatalysts by simultaneously regulating their electronic and pore structure.