Novel visible-light-driven direct Z-scheme CdS/CuInS2 nanoplates for excellent photocatalytic degradation performance and highly-efficient Cr(VI) reduction

Abstract A series of visible-light-driven direct Z-scheme CdS/CuInS 2 nanoplates were fabricated by a facile one-step hydrothermal method, and the molar ratio of CdS to CuInS 2 was optimized. The highest visible-light photocatalytic degradation activity of Z-scheme (1:0.03) CdS/CuInS 2 heterojunction is about 4 times than that of pure CuInS 2 , which is due to the narrowest band gap, the largest BET surface area, the most efficient charge separation and transfer, and the synergistic effect between CdS and CuInS 2 . Meanwhile, Z-scheme (1:0.03) CdS/CuInS 2 heterojunction also exhibits excellent photocatalytic reduction activity with almost 100% of aqueous Cr(VI) reduction efficiency in absence of hole scavengers after 60 min. The special significance is that Z-scheme (1:0.03)CdS/CuInS 2 heterojunction shows excellent stability in five degradation cycles, and can effectively treat real pharmaceutical wastewater with 76.5% COD removal efficiency with aid of H 2 O 2 in 13 h, indicating that Z-scheme CdS/CuInS 2 has a promising prospect in real pharmaceutical wastewater treatment.