BSA mediated Ag@Bi2S3 composites: synthesis, characterization, photodegradation of mixed dyes via metal-semiconductor interface, antimicrobial and antioxidant activities

Abstract

Nowadays, the development of metal-metal sulfide interface semiconductors using green approach is best material for the photocatalytic and biological applications. Here, we provided for the first time, an environmentally friendly route to fabricate bovine serum albumin (BSA) assisted Ag@Bi2S3 composites through a metal-metal sulphide interface via a simple hydrothermal method for the evaluation of photochemical and biological applications. The synthesized composites were characterized by UV–vis DRS, PL, XRD, TEM, and N2 adsorption-desorption isotherms. The UV–vis DRS and PL spectra show that the obtained nano-sized Ag@Bi2S3 composite displays enhanced visible-light absorption and a decreased fluorescence emission compared to that of Bi2S3 nanorods (NRs). The photocatalytic performances of the synthesized composites were evaluated by the degradation of the single (RhB and MB) and mixed dye (RhB+MB) under sunlight irradiation. The results indicated that the Ag@Bi2S3 composite exhibits superior photocatalytic activity (98.38%) than that of individual Ag NPs and Bi2S3 NRs due to the synergistic effect of Ag and Bi2S3 nanophases in the Ag@Bi2S3 composite, which results in an effective charge separation, fast electron transfer from Ag to Bi2S3, and a low recombination of photo-induced electron-hole pairs. The Ag@Bi2S3 composite also has good recycling stability up to 5 cycles and its mechanism also investigated. The evaluation of reactive species during the photocatalytic reaction was also carried out. Further, the effects of Bi2S3 and Ag NPs on the antimicrobial and antioxidant activity of the resultant Ag@Bi2S3 composite were also systematically investigated.