Structure, electrical properties and reaction mechanism of (Ba0.85Ca0.15)(Zr0.1Ti0.9)O3 ceramics synthesized by the molten salt method

Lead-free (Ba0.85Ca0.15)(Zr0.1Ti0.9)O3 (BCZT) ceramics with excellent electrical properties were successfully synthesized by a molten salt method (MSS). The submicron BCZT powders with pure perovskite phase were obtained by adjusting the KCl-NaCl content that was used as the eutectic salt. The effects of salt content and reaction temperature on the structure and properties of the BCZT materials were systematically investigated. Comparing with BCZT ceramics prepared by solid state method (SS), the reaction temperature of BCZT ceramics synthesized by MSS decreased approximately 200 °C. Moreover, BCZT ceramics sintered at 1360 °C with 50% eutectic salt showed the most outstanding electrical properties, which are as follows: d33 = 604 pC/N, kp = 57%, Ps = 17.11 µC/cm2, Pr = 9.98 µC/cm2, εm = 15872, εr = 2654 and tan δ = 0.013. In addition, this work revealed a possible reaction course processes and mechanism about MSS. The results provide a new design to optimize the performance of BCZT lead-free piezoelectric ceramics.