Enhanced piezoelectric property in quenched BiFeO3-based piezoceramics: role of defects and mesophase

The preparation of high performance BiFeO3-based piezoceramics has always been a research hotspot in the field of functional materials. Herein, the proposed quenching strategy effectively increased the piezoelectric coefficient d33 to 151 pC N−1, which is 21% higher than that of the conventional sintered counterpart. The mechanism of quenching to enhance piezoelectric performance mainly includes two points: on the one hand, the reduction in the content of oxygen vacancies caused by quenching is conducive to reducing the leakage current density, thereby promoting the increase of the poling field of the sample; on the other hand, the quenching treatment is beneficial for freezing the high-temperature state of the material, partially stabilizing the mesophase of FeBi5Ti3O15, and in turn realizing the modulation of the domain configuration. The easy-to-operate process provides valuable indications to conquer the main challenges for the BF-based piezoceramics applications.