Assessing the photocatalytic activity of visible light active Bi₂S₃-based nanocomposites for Methylene Blue and Rhodamine B degradation

High levels of organic compounds, notably synthetic dyes like Methylene blue (MB) and Rhodamine B (RhB), in untreated effluents have become a major environmental concern, endangering human health and ecosystems. These dyes are difficult to remove due to their non-biodegradable nature, prompting extensive research in this area. Photocatalysis has emerged as a promising, environmentally friendly method that only requires a light source and a photocatalyst for pollutant degradation. Bismuth sulfide (Bi₂S₃) stands out among other photocatalytic materials due to its narrow band gap, strong light absorption in the visible range, and nontoxicity, making it a good candidate to improve the overall photocatalytic efficiency. Therefore, this review article focuses on recent advances in Bi₂S₃-based nanocomposites and their role in the effective degradation of organic pollutants, particularly MB and RhB, through enhanced photocatalytic mechanisms.