Superior photodegradation and antibacterial activity of r-GO supported ternary nanocomposite of doped transition metal compounds

Abstract In this research, we have fabricated cerium-doped nickel ferrite (NiCe0.04Fe1.96O4, C.NFO) and iron-doped cerium oxide (Ce0.96Fe0.04O2, F.CO) via a simple co-precipitation approach. The doped samples were supported with r-GO nanosheets via facile ultra-sonication methodology to develop ternary nanocomposite (C.NFO/F.CO/r-GO). The fabricated samples were characterized and their photodegradation and bactericidal aptitude were examined by using model organic chemicals (methylene blue (MB), SF-dyes, and Rhodamine-B (Rh–B)) and bacterial strains (Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus)), respectively. The results of the application studies revealed that fabricated C.NFO/F.CO/r-GO ternary nanocomposite exhibited excellent potential towards the photodegradation and bactericidal activities due to its photo-generated reactive species ( H O ⋅ , O ‾ 2 ⋅ & H 2 O 2 ). Distinctively, as-synthesized ternary nanocomposite, after 1.5 h of visible light irradiation, decomposed 99.12% MB-dye, 72.78% SF-dye, and 77.9% Rh–B dye. The reusability tests of C.NFO/F.CO/r-GO photocatalyst over MB dye revealed that it has excellent stability and can be reused four times with only ~5% loss in the photocatalytic efficiency. Furthermore, the fabricated ternary nanocomposite also showed outstanding bactericidal activity towards the gram-positive (S. aureus) and gram-negative bacterial strains (E. coli). In fact, like organic dyes, the main constituents of the bacterial cell wall are also organic molecules and are liable to decompose via redox reaction driven by photo-generated reactive species. Our fabricated ternary nanocomposite has an excellent aptitude to eliminate the toxic dyes and kill the bacteria present in the industrial effluents.