Effect of CaO Dopant on the Dielectric Properties of NiO

Abstract

CaxNi1-xO was prepared by conventional solid state reaction. The properties of undoped and CaO doped NiO ceramics have been studied. The raw mixture of CaO and NiO were ball milled for 24 hours. The samples were calcined at 1000°C for 2 hours, pressed into pellet shape at 200 MPa and sintered at 1300°C for 4 hours. The sintered samples were subjected to XRD, Scanning Electron Microscopy (SEM) and Impedance Analyzer for phase identification, microstructural observation and dielectric analysis. The grains size becomes larger with the increment of dopant amount. Enhanced dielectric constant was observed for all Ca doped NiO at the frequency range from 100 Hz to 1 MHz. The dielectric constant of sintered CaxNi1-xO decreased with an increasing frequency. The result indicates that Ca ions have effectively changed the properties of NiO.