Photochemical production of hydrogen peroxide by digging pro-superoxide radical carbon vacancies in porous carbon nitride
Yang Ding, Soumyajit Maitra, Daniel Arenas Esteban, Sara Bals, Henk Vrielinck, Tarek Barakat, Subhasis Roy, Gustaaf Van Tendeloo, Jing Liu, Yu Li, Alexandru Vlad, Bao‐Lian Su
Abstract
Artificial photosynthesis of H2O2, an environmentally friendly oxidant and a clean fuel, holds great promise. However, improving its efficiency and stability for industrial implementation remains highly challenging. Here, we report the visible-light H2O2 artificial photosynthesis by digging pro-superoxide radical carbon vacancies in three-dimensional hierarchical porous g-C3N4 through a simple hydrolysis-freeze-drying-thermal treatment. A significant electronic structure change is revealed upon the implantation of carbon vacancies, broadening visible-light absorption and facilitating the photogenerated charge separation. The strong electron affinity of the carbon vacancies promotes superoxide radical (⋅O2−) formation, significantly boosting the H2O2 photocatalytic production. The developed photocatalyst shows an H2O2 evolution rate of 6287.5 μM g−1 h−1 under visible-light irradiation with a long cycling stability being the best-performing photocatalyst among all reported g-C3N4-based systems. Our work provides fundamental insight into highly active and stable photocatalysts with great potential for safe industrial H2O2 production.