High permittivity in zr doped NiO ceramics

We report on measurements of the dielectric permittivity of NiO-based ceramics doped with Zr (ZNO). Samples were prepared by the traditional solid-state reaction method. The concentration of Zr has an effect on the dielectric properties of ZNO ceramics. High permittivity values (similar to 10(4)) were observed which remain almost constant from 200 K to 350 K at low frequencies. The high-dielectric-constant response of the ZNO ceramics is attributed mainly to a grain boundary (internal) barrier layer capacitance. (c) 2007 American Institute of Physics.