Effect of Cd2+ concentration on ZnFe2O4 nanoparticles on the structural, optical and magnetic properties

Simple, cost effective and low temperature synthesis of pure and Cd2+ doped zinc ferrite nanoparticles have been successfully synthesized by a microwave assisted combustion method using metal nitrates as oxidizing agent and l-arginine as a reducing agent. The stoichiometric ratio of precursors taken was 1:2. X-ray diffraction, Rietveld, FTIR, HRSEM, DRS, PL, and VSM techniques are carried out to characterize the samples for the structural phases, functional groups, morphology, optical and magnetic properties. Upon the combustion method, the crystallinity and size variation of the nanoparticles were decreased from 42 nm to 12 nm with increasing the concentration of the dopant. The lattice parameter of the spinel structure increases when the size of the nanoparticles reduced. FTIR spectra confirmed the presence of metal oxides absorption bands at lower and higher frequency regimes, due to tetrahedral, and octahedral stretching vibrations respectively. HRSEM images showed the presence of spherical particles in the nano-regime. The bandgap energy of the samples was estimated by diffuse reflectance spectra and it decreased with increasing dopant concentration which was calculated from Tauc's relation. Photoluminescence (PL) spectroscopy used to investigate the emission of the samples with the excitation wavelength at 414 nm and emission at 486 nm. Vibrating sample magnetometer under applied magnetic field was used to carry out the magnetic measurements and it revealed at decrease in saturation magnetization and an increase in coercivity with an increase in the concentration of Cd2+ ions. The microwave combustion method produces the ferrite nanoparticles as clean, non-toxic, environment-friendly with high yield of product in a shorter reaction time. The future plan of this research is to synthesize highly active catalyst for the photocatalytic mineralization of industrial effluent in large scale.