Enhanced photocatalytic efficiency of a novel GO/Bi2SO5/AgBr ternary heterojunction for the degradation of tetracycline and rhodamine B

Water contamination by pharmaceuticals and organic dyes requires advanced photocatalysts to degrade these pollutants effectively. This study used an in-situ precipitation method to synthesize a novel GO/Bi 2 SiO 5 /AgBr heterojunction photocatalyst and thoroughly analysed it for its structure, optical properties, and photocatalytic performance. Characterization techniques confirmed the successful integration of GO, Bi 2 SiO 5 , and AgBr, with BET analysis showing a significant surface area increase from 20.50 m 2 /g to 47.44 m 2 /g. Incorporating GO and AgBr extended visible-light absorption and improved charge separation, as demonstrated by UV-Vis DRS, PL spectra, EIS, and Mott-Schottky measurements. As a result, the photocatalyst achieved high degradation efficiencies of 95.83 % for tetracycline in 60 min and 97.02 % for Rhodamine B in 30 min under visible light. This improvement is attributed to the surface plasmon resonance (SPR) effect of Ag in AgBr and the electron-accepting ability of GO, which enhances charge transfer. Additionally, the photocatalyst showed excellent stability and reusability over five cycles. Quenching experiments confirmed that h⁺ and •O 2 ⁻ radicals were key in pollutant degradation. This study provides a promising strategy for designing efficient, visible-light-driven photocatalysts for sustainable water treatment. • Heterojunction composites of GO/Bi 2 SiO 5/ AgBr synthesized via in-situ precipitation. • GO/Bi 2 SiO 5 /AgBr composites achieved ∼96 % tetracycline degradation in 60 minutes. • 97 % Rhodamine B degradation in 30 minutes was achieved with optimal performance. • Material maintained stability after five cycle runs. • Scavenging experiment shows h + and •O 2 – are dominant reactive species for degradation.