Ag-SPR and semiconductor interface effect on a ternary CuO@Ag@Bi2S3 Z-scheme catalyst for enhanced removal of HIV drugs and (photo)catalytic activity

Abstract

The development of ternary composites has gained great interest as they can be used as a catalyst in environmental remediation due to the transfer between different semiconductor nanoparticles because the difference in the band edge positions creates a potential gradient at the composite interface. Herein, for the first time, we reported a novel CuO@Ag@Bi₂S₃ ternary composite as a Z-scheme catalyst via homogeneous precipitation of Ag particles onto CuO and Bi₂S₃ by an ultrasonication method, wherein CuO nanoparticles were fabricated from the reduction of a Cu(II)–Schiff base complex. In the ternary composite, ∼10 nm Ag particles were uniformly dispersed on Bi₂S₃ and surrounded by CuO NPs, as demonstrated by TEM. Compared to the binary structures Ag@CuO, Ag@Bi₂S₃, and CuO@Bi₂S₃, the CuO@Ag@Bi₂S₃ ternary composite exhibits remarkably efficient catalytic activity for the removal of HIV drugs such as stavudine and zidovudine, and degradation of environmental pollutants (MB/RhB/MB + RhB, monocrotophos, and 4-nitrophenol). The framework of the formation of the composite, semiconductor behavior, high surface area, lowering of the electron–hole recombination, and the formation of a large number of ˙OH radicals are the crucial factors for the outstanding degradation of drugs and environmental pollutants by the CuO@Ag@Bi₂S₃ ternary composite through a Z-scheme mechanism. This work reveals that the CuO@Ag@Bi₂S₃ ternary composite is efficient at catalyzing not only the degradation of organic pollutants but also the removal of drugs, which might pave the way for its direct use in industry for environmental remediation.