Ultrahigh electrostrains of lead-free (Ba,Ca)(Ti Zr)O3 piezoelectric ceramics via defect engineering

作者：Li, Xueshuo; Fu, Jian^*; Yang, Yuhan; Li, Zhenchang; Song, Wenxuan; Zuo, Ruzhong

来源：Journal of Materials Science, 2022, 57(22): 10233-10241.

DOI：10.1007/s10853-022-07281-x

• PHASE-DIAGRAM
• STRAIN
• TEMPERATURE
• SITE

Piezoelectric ceramics with large electric field-induced strain are of great importance for actuator applications. Unfortunately, BaTiO3-based ceramics usually exhibit relatively low strain in spite of their high large-signal piezoelectric coefficient d(33)*. In this study, an ultrahigh electrostrain with a value of similar to 0.242% (d(33)* = 1210 pm/V) at 2 kV /mm is achieved in MnO2-doped (Ba,Ca)(Ti,Zr)O-3 (BCTZ)-based lead-free piezoelectric ceramics via defect engineering, which is similar to 82% higher than that of the undoped sample. Detailed structural analysis in combination with various electrical property measurements revealed that such an ultrahigh strain should be attributed to the internal bias field E-i as a result of defect dipoles between the acceptor Mn ions and the oxygen vacancies, accompanied by the recoverable strain and the enhanced asymmetry of strain vs. electric field curve. The results demonstrate that the studied compositions might have great potential for applications of lead-free actuator piezoelectric ceramics.