Abstract
In this work, we report the structural, electrical and Mossbauer spectroscopic studies of Ni0.5Cu0.25Zn0.25Fe2-xInxO4; x = 0. 0.1, 0.2, 0.3, 0.4 spinel ferrites, synthesized by using citrate-nitrate precursor auto combustion method. In order to investigate the formation of the spinel phase, thermal analysis (DTA-TGA) was performed. The phase recognition, crystallinity and morphology of as prepared samples were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The crystal structure was found to be cubic spinel and the lattice constants increased linearly with increasing quantity of In3+ ions. Room temperature Mossbauer spectrum of x = 0 sample shows four sextets due to Fe3+ ions at octahedral and tetrahedral sites. The ac conductivity was studied as a function of frequency which revealed that the hopping of electrons between Fe3+ <-> Fe2+ as well as the hole hopping between Ni3+ <-> Ni2+ are responsible for conduction mechanism in the studied compound.