Boosting oxygen activation by CoP/carbon nitride photocatalyst in low-concentration HS oxidation

Aerobic photocatalytic oxidation is considered as an efficient and green method to remedy low-concentration H 2 S pollutants associated with the energy and chemical industries. However, the fabrication of a sulfur-resistant catalyst with good performance is a great challenge because of the poisoning effect of H 2 S and the difficulty in oxygen (O 2 ) activation. Herein, a photocatalytic hybrid material composed of chemically stable cobalt phosphide (CoP) and structural base-enriched carbon nitride (CN) was developed for the efficient oxidation of H 2 S, which could achieve 95% H 2 S conversion, and its service time could last more than 35 h with over 80% H 2 S conversion. Reflecting from the characterizations and theoretical simulations, the enhanced H 2 S conversion was on account that CoP could stimulate the electrons shuttling from the photocatalytic system towards the gaseous O 2 , facilitating the production of critical superoxide radical via the O 2 reduction process and accelerating the surface H 2 S oxidation process. This work provides new insights into the design of a sustainable photocatalytic oxidation system for the treatment of chemically active contaminants through constructing stable interfacial electron transfer channels for prominent O 2 activation. The introduction of CoP could efficiently facilitate the electron transfer from CN towards O 2 and enrich the production of ·O 2 − , which was indispensable in photocatalytic H 2 S oxidation.