Adsorption enrichment-localization photocatalyst: Enhanced photooxidation over activated carbon/red phosphorus

Red phosphorus (RP) is an excellent semiconductor photocatalyst , but suffers from a narrow band gap, small specific surface area, few active sites and low light quantum efficiency, which limits its practical application. The immobilization of RP on supports with large surface is an emerging attempt to improve photocatalytic performance. In this paper, the hydrothermally treated RP (HRP) was immobilized on the inexpensive activated carbon (AC) support. The ratio optimization experiments showed that the AC 7 /HRP (mass fraction of AC was 7%) composite showed the highest against Rhodamine B (RhB), and the κ values were 0.234 min −1 , which were 3.8 times higher than that of HRP. The mechanism of activity enhancement suggested that a special structure was formed between HRP and AC, which not only inhibited overgrowth and agglomeration of HRP, but also acted as a micro-reaction system for adsorption-localization photocatalytic reactions. In addition, AC had excellent optical properties , which can improve the photoelectric conversion and the separation of photogenerated electron and hole (e − -h + ) pairs, thus improving the photocatalytic activity . Therefore, the AC 7 /HRP composite was eco-friendly, cost-effective, and had strong photocatalytic oxidation properties, which was expected to be used in practical wastewater treatment.