A novel P-doped g-C3N4/Zn0.8Cd0.2S composite photocatalyst for degradation of methylene blue under simulated sunlight

Abstract P-doped g-C3N4/Zn0.8Cd0.2S (PCN/ZS) heterostructures have been constructed via a two-pot method and investigated as catalysts for photocatalytic degradation of methylene blue (MB) under simulated sunlight. XRD, UV–vis spectrometry, FT-IR, PL, TEM, and EDS were used to provide structure information of the as-prepared samples involving the formation of the ZS solid solution, the existence of the heterostructure between PCN and ZS, the graphite-like structure of PCN and successful incorporation of P into the framework of CN. The enhanced catalytic performance of PCN/ZS for the degradation of MB compared with pure PCN and ZS benefited from elevated light-harvesting property, favorable transport and separation efficiency of photoinduced charge carriers through the construction of the heterojunction originated from in situ growth of the ZS solid solution on PCN. The degradation efficiency (D) had a maximum of 91.3% with a given mass ratio of PCN to ZS (y = 0.5 wt%). h+ and O2− proved the main reactive species for MB degradation, based on which the possible reaction path was proposed.