Graphite carbon nitride/ZnIn2S4 heterojunction photocatalyst with enhanced photocatalytic performance for degradation of tetracycline under visible light irradiation

It is a widespread concern to address the antibiotics in water with low-cost and eco-friendly photocatalysts that could efficiently harvest solar light. Herein, we designed an efficient photocatalyst by integrating the lamellar gC(3)N(4) into Znln2S4 microflowers through a one-step hydrothermal method. The as-synthesized g-C3N4/Znln2S4 heterojunction photocatalysts exhibited evidently enhancement on the photocatalytic activities for the degradation of tetracycline (100 mL, 20 mg/L) compared with pristine g-C3N4 and Znln(2)S(4). Significantly, g-C3N4/Znln(2)S(4) composite with loading 50 wt.% g-C3N4 showed the highest photocatalytic performance (almost 100% degradation within 120 min), which was around 40 and 22.8 times higher than that of g-C3N4 and Znln(2)S(4), respectively. This enhanced photocatalytic activity of g-C3N4/Znln(2)S(4) is mainly attributed to the formation of heterostructure that can efficiently promote the transfer of photoinduced electrons and holes between g-C3N4 and Znln(2)S(4), restricting the recombination of electron-hole pairs. In addition, a possible mechanism was also proposed.