Electrical properties of Li and Nb modified BiFeO3 ceramics with reduced leakage current

The lead-free BiFe 1- x (Li 0·5 Nb 0.5 ) x O 3 ceramics with x  = 0.00, 0.01, 0.02, 0.04, 0.06, and 0.08 were modified by Li/Nb co-doping. X-ray diffraction measurements indicated that all the ceramics had a rhombohedral distorted perovskite structure and secondary phases appeared when x  = 0.00, 0.04, and 0.06. The BiFeO 3 ceramics with a small amount of Li/Nb co-doping exhibited improvements in the remnant polarization (2 P r ) and ferroelectric P - E loop shape compared with the results of pure BiFeO 3 (BFO). The decreased dielectric loss and leakage current indicated that proper Li/Nb co-doping for the Fe-site in BFO was a promising route to improve the leakage behavior and enhance the resistivity. These improved electrical properties were related to the reduction of oxygen vacancies and suppression of the formation of Fe 2+ . The leakage mechanism was also discussed and analyzed.