Effect of sintering temperature on microstructure and electrical properties of Mn1.2Co1.5Ni0.3O4 ceramic materials using nanoparticles by reverse microemulsion method

The high performance Mn1.2Co1.5Ni0.3O4 (MCN) ceramic materials are successfully fabricated using nanoparticles which are synthesized by the reverse microemulsion method. The morphology, crystal structure and particle size distribution of MCN nanoparticles are characterized by the XRD, SEM, TEM and HRTEM. The results show the well single tetragonal spinel structure and the narrow particle size distribution about 40 nm. As the sintering temperature increasing from 1000 to 1250 °C, all the MCN ceramic samples prepared by above-mentioned nanoparticles show the same single tetragonal spinel structure. The thermal sensitive properties with high values of ρ25, B25/100, Ea, and α25 of MCN ceramics at different sintering temperatures are in the range of 68,805–497,730 Ω cm, 4578–5159 K, 0.395–0.445 eV, and −5.2 to −5.8 %/K, respectively. These features indicate that the microstructure and electrical properties of MCN ceramics are relevant to the sintering temperature.