Synergistic effects of a self-generating electricity photoelectrocatalytic system with N-doped carbon quantum dots in BTEX degradation

The photocatalytic (PC) degradation process of volatile organic compounds (VOCs) has been consistently restricted by the rapid recombination of photogenerated electrons and holes. To solve this problem, in this study, a novel photoelectrocatalytic (PEC) coupled system was constructed by integrating a single-chamber direct glucose fuel cell (SDGFC), which is capable of self-generating electricity, into the conventional PC system. The coupling system can inhibit the recombination of photogenerated electrons and holes by continuously generating a current without an applied power source. In addition, nitrogen-doped carbon quantum dots (N-CQDs) were prepared using biomass gelatin. This was employed as a PC material for the catalytic layer of the air cathode in the above coupling system, and the efficient degradation of benzene series (BTEX) was made easy by regulating the content of the N element. Notably, the N-CQDs under the optimal regulation ratio showed excellent optical properties and degradation performance, achieving an impressive PEC degradation rate of over 80 % for BTEX within 180 min. High-performance N-CQDs complement the novel PEC coupling system of self-generating electricity and provide robust support for BTEX degradation.