Giant Dielectric Permittivity in Li and Nb Doped NiO

摘要

Giant dielectric permittivity Li and Nb co-doped NiO (abbreviated as LNNO) ceramics are prepared by sol-gel method. The dielectric properties have been investigated at room temperature. The ceramics exhibit a giant low-frequency dielectric constant (～10~5) with low loss factor (～ 0.05-0.07) at room temperature. The concentration of Li dopant has a remarkable effect on the dielectric properties of the LNNO ceramics. It's found that the dielectric constant decreases significantly as the content of Li increases. The high dielectrics property is attributed to the structure with semiconductor grain and Nb-rich insulating grain boundary.