Giant dielectric permittivity observed in Li and Zr co-doped NiO

The dielectric properties of Li and Zr co-doped NiO (abbreviated as LZNO) ceramics have been investigated. A high dielectric constant (∼104) is observed which remains almost constant in a wide temperature (233 K–373 K) and frequency (100 Hz–10 MHz) range. Analysis of the ceramic micro structure and composition indicates that the alkali Li has an excellent effect on the dielectric properties of LZNO ceramics. The increase of dielectric constant with Li concentration is associated with a decrease of dielectric loss. The dielectric behavior of LZNO is discussed based on the internal boundary layer capacitor model.