Biofilm-Assisted Fabrication of Ag@SnO₂-g-C₃N₄ Nanostructures for Visible Light-Induced Photocatalysis and Photoelectrochemical Performance

Development of advanced materials with a benign environmentally friendly approach for heterogeneous visible light photocatalysis is always preferable. An environmentally favorable approach was used to anchor silver nanoparticles (Ag NPs) to tin oxide-decorated-graphitic carbon nitride (SnO 2 - g -C 3 N 4 ) using a biofilm as a green reducing tool for the biogenic synthesis of 1–6 mM Ag@SnO 2 - g -C 3 N 4 nanostructures (NSs). The fabricated NSs were characterized using sophisticated techniques. The developed Ag@SnO 2 - g -C 3 N 4 NSs showed a well-defined spherical-shaped Ag NPs anchored to SnO 2 - g -C 3 N 4 NSs. The synthesized NSs were applied for photocatalytic degradation of hazardous dyes and photoelectrochemical studies. A comparative investigation of Ag@SnO 2 - g -C 3 N 4 NSs for the visible light-assisted photocatalytic degradation of Methylene blue (MB), Congo red (CR), and Rhodamine B (RhB) was performed. The photocatalytic degradation of MB, CR, and RhB reached ∼99% in 90 min, ∼98% in 60 min, and ∼94% in 240 min, respectively. The anchoring of Ag NPs to SnO 2 - g -C 3 N 4 NSs further enhanced the visible light photocatalytic degradation of the dyes due to surface plasmon resonance and by lowering the recombination of the photogenerated electrons and holes. Further, high electron transfer ability of Ag@SnO 2 - g -C 3 N 4 NSs was investigated by electrochemical impedance spectroscopy to understand the mechanistic insights of the excellent activity under visible light irradiation. Hence, the present study provides an environmentally benign approach for the synthesis and excellent visible light effective photocatalysis and photoelectrochemical performance.