Spinel CoFe2O4 nanoparticles were synthesized by a simple, economical, and eco-friendly hydrothermal method (HM) using metal nitrates and polyvinyl pyrrolidone. The structural, morphological, and magnetic properties of the products were determined and characterized in detail by X-ray diffraction (XRD), high-resolution scanning electron microscopy (HR-SEM), energy-dispersive X-ray spectroscopy (EDX), photoluminescence (PL) spectroscopy, vibrating sample magnetometry (VSM), and Brunauer-Emmett-Teller (BET) surface area analysis. Key parameters influencing the structural performance, such as particle size and shape, annealing temperature, functionalization, and magnetic properties, have been comprehensively discussed. The effect of the catalyst and solvent on the catalytic oxidation of benzyl alcohol using the CoFe2O4 nanoparticle catalyst prepared by hydrothermal method was also investigated.