Tailoring of electrical properties in nanostructured (NiO)0.25(Fe2O3)0.75 composite and compound for sensing applications

Abstract

Abstract Compound and composite of the (NiO)0.25(Fe2O3)0.75 nanoparticles have been prepared by without water and surfactants (WOWS), Sol-gel method. Synthesized nanoparticles are calcined at 500 °C/2 h and pellets are sintered at 550 °C/1 h. The compound and composite showed cubic lattice and rhombohedral crystallographic lattices respectively. Morphological analysis is done by Scanning electron microscope and Transmission electron microscope. UV characterization was done to calculate band gap energies for both samples. DC electrical conductivity as a function temperature from 373.15 to 703.15 K was done by two-probe method. DC conductivity has been explained by hopping mechanism. Activation energies were calculated from Arrhenius plots. AC electrical properties namely; dielectric constant, dielectric loss tangent, ac conductivity and impedance were measured as a function of frequency (20 Hz–3 MHz). AC electrical properties were explained by Maxwell-Wegner model, Koop’s theory and Johnsher’s power law. Composite of (NiO)0.25(Fe2O3)0.75 showed enhanced properties as compared to compound.