This study investigates the magnetic, thermal, and electrical properties of Co0.72Sr0.07Ni0.21Fe2O4 ferrite nanoparticles under different conditions, including as-prepared, irradiated (at a dose of 100 kGy in CO2 atmosphere), and aged (at 1000°C). The magnetic properties are analyzed using M-H loops, revealing that the aged sample exhibits the highest magnetization values. The observed decrease in magnetization after irradiation and increase after aging is consistent due to the presence of a new phase (γ-FeOOH) in the irradiated sample that XRD confirms. Electrical conductivity measurements demonstrate that the aging sample exhibits the highest electrical conductivity due to increased grain boundaries, while the irradiated sample shows increased conductivity attributed to oxygen vacancies. As well as the nanocomposite of PVP and Co0.72Sr0.07Ni0.21Fe2O4 nanoparticles aged (at 1000°C) is found to be effective in degrading the Toluidine Blue (TB) dye through catalytic oxidation and photodegradation mechanisms. The catalytic degradation of TB dye provides valuable insights into the potential application of these ferrite nanoparticles in environmental remediation and wastewater treatment. Also, nanocomposite demonstrated significant antimicrobial activity against five pathogenic bacterial strains commonly found in contaminated water, with superior effectiveness against Gram-negative bacteria, particularly Salmonella enterica and Pseudomonas aeruginosa, suggesting its potential as an effective water treatment agent. The novelty and the aims are to analyze the changes in magnetization and conductivity of the nanoparticles under different conditions, including as-prepared, irradiated, and aged samples. Additionally, the catalytic efficiency of the aged nanoparticles in degrading Toluidine Blue (TB) dye is examined, providing insights into their potential application in environmental remediation and wastewater treatment.
