Facile combustion-synthesis, structural, morphological, vibrational, photoluminescence, dielectric, and electrical properties of ZnFe2O4 nanostructures: an effect of citric acid concentrations

In the current report, we have facilely synthesized the ZnFe2O4 nanoparticles (ZFO NPs) using the flash combustion route at 600 °C with various concentrations of citric acid (CA). The structural, vibrational, and elemental/homogeneity analyses through XRD, Raman, and energy dispersive X-ray spectroscopy/Scanning electron microscopy e-mapping confirmed the cubic phase and composition of synthesized ZFO NPs. The crystallite size was estimated using Scherrer and Williamson-Hall plot methods and noticed to be reduced with an increasing amount of CA in ZFO and found between 15 to 30nm, which was also supported by scanning electron and transmission electron microscopic studies. X-ray photoelectron spectroscopy analysis confirmed the synthesis of ZnFe2O4. The ZFO NPs were excited at 417nm to record the luminescence spectra and found the emission peaks at 456±2, 530±3, and 625±5nm. The dielectric constant was found to be between 147 and 165 with low loss values, and the electrical conductivity was found to be enhanced with CA content in ZFO NPs. The magnetic properties were also studied at 300K and disused. These outcomes indicate that the properties of ZFO NPs have been greatly influenced by crystallite/grain size variation, which resulted from different CA concentration-assisted synthesis of ZFO and possess the potential for optoelectronic and energy storage devices.