Superior ferroelectric properties and enhanced depolarization temperature simultaneously achieved in BNT-based ceramics

Bi0.5Na0.5TiO3-based ceramics with high remnant polarization P-r have shown outstanding potential in the application of high-power ferroelectric transducers. However, low depolarization temperature T-d is an obstacle for their application. Here, a composition design strategy was proposed to simultaneously improve the T-d and P-r in BNT-based materials. Ultrahigh P-r of 40.56 mu C/cm(2) and relative high T-d of 184 degrees C were synergistically achieved in (Bi0.5Na0.5)(Ti0.995Mn0.005)O-3 (BNMT) ceramics by adding 1.0 mol% BiGaO3 (BG), which is superior to other reported lead-free systems. The excellent ferroelectric properties were attributed to strengthen ferroelectric order as evidenced by increased rhombohedral distortion. Meanwhile, the enhanced depolarization temperature, increasing from 168 degrees C for x = 0% to 184 degrees C for x = 1.0%, can be ascribed to the suppression of the thermal-induced ferroelectric-relaxor phase transition by adding BG. Those results enable the BNMT-BG systems ceramics to be an attractive candidate for application in high-power supplies.

Automated summary

By adding BiGaO3 (BG), the depolarization temperature (T-d) and remnant polarization (P-r) of Bi0.5Na0.5TiO3-based ceramics have been simultaneously improved. The ceramics achieved ultrahigh P-r of 40.56 mu C/cm(2) and relatively high T-d of 184 degrees C, making them attractive candidates for high-power ferroelectric transducer applications.