LAUSR

Abstract Development of more efficient, low cost and sustainable (nano)catalysts for reduction of various pollutants in water is highly desirable and is still a major challenge. Herein, we report the immobilization of Cu(II)-5-(methylthio)-1H-tetrazole complex (Thiotet-Cu(II)) on Fe3O4/SiO2 superparamagnetic nanoparticles (NPs) through a versatile process and the application of the nanoparticles prepared as highly efficient and recyclable nanospherical catalysts. The as-prepared Fe3O4/SiO2-Thiotet-Cu(II) is used as a recyclable and highly active nanocatalyst in the reduction of hexavalent chromium [Cr(VI)], 4-nitrophenol (4-NP), Congo Red (CR) and Methylene Blue (MB) in aqueous media. The surface nature of Fe3O4 NPs changes after modification, which causes a notable increase in the catalytic prowess and antimicrobial performance. Moreover, the ensuing nanocatalyst remains high reduction efficiency of ~95% after nine cycles without meaningful loss of its efficiency and can be conveniently separated/decanted using an external magnet, demonstrates high recyclability, excellent chemical stability and high potential for practical environmental applications. The present protocol is clean and eco-friendly and does not use any toxic reductants.