The growing discharge of dye-contaminated wastewater from textile, leather, and chemical industries poses a serious environmental challenge, necessitating the development of efficient and sustainable remediation technologies. Visible-light-driven photo catalysis has emerged as a promising solution, and KBiFe₂O₅ has recently attracted attention as an effective photo catalyst owing to its unique structural and electronic properties. This interdisciplinary review presents a comprehensive overview of the photo catalytic potential of KBiFe₂O₅ for wastewater remediation, integrating perspectives from materials physics, chemistry, and environmental science. The layered crystal structure of KBiFe₂O₅, coupled with the presence of Bi³⁺ lone-pair electrons and Fe-O coordination, enables strong visible-light absorption and favourable charge carrier dynamics. These characteristics facilitate the generation of reactive oxygen species under illumination, which play a crucial role in the degradation of organic dye pollutants. Recent studies addressing structure-property relationships, optical behaviour, and charge transfer mechanisms are critically discussed to elucidate factors governing photo catalytic efficiency. Finally, existing challenges related to recombination losses, long-term durability, and practical implementation are identified, and future research directions are proposed. This review aims to bridge fundamental understanding and environmental application, promoting the advancement of KBiFe₂O₅- based photo catalysts for sustainable wastewater treatment.

Keywords: KBiFe₂O₅; Visible-Light Photo Catalysis; Wastewater Remediation; Environmental Sustainability;