Oxygen-assisted one-step fabrication and concomitant regulation of hierarchical carbon nanosheet assemblies with conjugated binding configurations for promoted H2O2 electrosynthesis

Abstract

Electrochemical two-electron oxygen reduction reaction (2e- ORR) is a straightforward and efficient route for H2O2 production. The facile fabrication and concomitant modulation of metal-free carbon with conjugated binding configurations is currently an essential obstacle for 2e− ORR toward electrochemical H2O2 generation. Herein, hierarchical porous O, N co-doped porous carbon (ONPC) nanosheet assemblies with multiple active motifs are developed for driving H2O2 electrogeneration from 2e- ORR. The pyrrolic-N and C = O configurations in ONPC facilitate the highly selective electrosynthesis of H2O2. The synthesis and concomitant regulation of pyrrolic-N and C = O of carbon materials are achieved via a simple one-step oxygen-assisted self-activation, self-template and self-doping strategy. The resulted amorphous ONPC-700 with the optimal pyrrolic − N and C = O active motifs facilitates the 2e− ORR toward H2O2 electrosynthesis. A high H2O2 yield of 0.319 mol g−1 h−1 with 80–93% H2O2 selectivity, good methanol tolerance, and long-term stability in 0.1 M KOH can be achieved. This study inspires to develop and regulate metal-free carbon materials with dual active motifs via one-step oxygen-mediated pyrolysis of low-cost/non-toxic precursor for H2O2 electrosynthesis.