Sol-gel method for synthesis and characterization of nano crystalline ferrite materials NiCuZn

Abstract

The effects of Cu2+ substitution and Zn2+ substitution on the nickel based and copper based spinel ferrites have been investigated.Six series of spinel ferrites with nominal compositions Ni0.6Cu0.2Zn0.2Fe2O4, Ni0.4Cu0.4Zn0.2Fe2O4, Ni0.2Cu0.6Zn0.2Fe2O4, and Ni0.6Cu0.2Zn0.2Fe2O4 , Ni0.4Cu0.2Zn0.4Fe2O4 , Ni0.2Cu0.2Zn0.6Fe2O4, were prepared by the sol-gel auto combustion technique. The samples were characterized by SEM, X-ray diffraction, TEM, FTIR, UV, dielectric properties and magnetic properties measurement. Grain size was measured from the scanning electron micrographs. The average grain size of sintered ferrites was within the range of 25 nm to 40 nm and 124 nm to 219 nm for Ni0.8-xCuxZn0.2Fe2O4 and Ni0.8-xCu0.2ZnxFe2O4 ferrites respectively. The x-ray diffraction was done through Philips x-ray diffractometer using CuKr radiations ((and#955; = 1.5405 and#506;).Lattice constant and sintered density increased with increase in copper concentration in case of Ni0.8-xCuxZn0.2Fe2O4 (x=0.0,0.2,0.4,0.6) ferrite, whereas it increase with increase in zinc concentration in case of Ni0.8-xCu0.2ZnxFe2O4 ferrites .X-ray density and porosity decreases in both prepared ferrites as copper and zinc concentration increases respectively. newlineTEM images with SAED patterns indicates that particles are aggregated during annealing and metal ion incorporation, and concludes that the nanoparticles are organized into an isooriented attached structure by sharing identical lattice planes. The FTIR spectroscopy confirms the single phase nature of the prepared sample. newlineThe dielectric constant was measured as a function of Cu substitution in Ni0.8-xCuxZn0.2Fe2O4 ferrites as well as a function of Zn concentration in Ni0.8Cu0.2ZnxFe2O4 ferrites.The dielectric constant and dielectric loss factors were measured as a function of frequency for all the samples in the range of 100 Hz to 1 MHz at room temperature and 700o C.