Photodegradation of methylene blue dye using light driven photocatalyst-green cobalt doped cadmium ferrite nanoparticles as antibacterial agents

A cobalt-doped cadmium ferrite nanoparticle (Co_xCd_1-xFe₂O₄; x = 0, 0.2, 0.4, 0.6, 0.8, 1) was synthesized using curd as fuel during combustion. The symphonized nanoparticle's crystalline structure, size, morphology, photoluminescence, and optical properties are analyzed using PXRD, FTIR, SEM, HRTEM, XPS, UV–visible, and photoluminescence spectroscopies. PXRD analysis indicates that synthesized nanoparticles have a cubic spinel structure and that as cobalt doping increases, crystalline size and the lattice parameter decrease. FTIR analysis confirms tetrahedral and octahedral sites for vibrational stretching modes. Further SEM and HRTEM analyses reveal the morphology of the synthesized nanoparticles, which are agglomerated and have a nanoflakes-like structure. Furthermore, X-ray photoelectron spectroscopy reveals the elemental composition, oxidation, and transition states of CDCF NPs. UV–Vis spectroscopy discloses absorption, band gap regarding prepared NPs, and band gap deductions with increased cadmium substitution. The effect of cadmium substitution on luminescence is demonstrated by photoluminescence spectroscopy. Under visible light, photodegradation of the dye Methylene Blue in the presence of photocatalyst CDCF nanoparticles indicates that Co_0.4Cd_0.6Fe₂O₄ has higher degradation activity than other NPs. Antibacterial activity was performed for Gram-positive (S. aureus) and Gram-negative (Shigella) in the presence of synthesized Nano-particles. Activity results revealed that Co_0.6Cd_0.4Fe₂O₄ and CO_0.2Cd_0.8Fe₂O₄ NPs show an excellent zone of inhibition for S. aureus and Shigella bacterial strains.