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

The lead-free BiFe1-x (Li0.5Nb0.5)(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 BiFeO3 ceramics with a small amount of Li/Nb co-doping exhibited improvements in the remnant polarization (2P(r)) and ferroelectric P-E loop shape compared with the results of pure BiFeO3 (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 Fe2+. The leakage mechanism was also discussed and analyzed.

Automated summary

The lead-free BiFe1-x (Li0.5Nb0.5)(x)O-3 ceramics were modified by Li/Nb co-doping with different x values. The results showed that proper Li/Nb co-doping could improve the electrical properties of the ceramics, reduce dielectric loss and leakage current, and enhance resistivity.