Simultaneous Realization of Good Piezoelectric and Strain Temperature Stability via the Synergic Contribution from Multilayer Design and Rare Earth Doping

摘要

Niobate-based lead-free piezoceramics have attracted wide attention dueto their excellent piezoelectric properties. Although the temperature sensitivityof piezoelectricity or strain in one sample has been solved to a certainextent, how to simultaneously improve the temperature stability of both inone sample is still an issue. Herein, by constructing multilayer compositeceramics and doping Ho element, both improved piezoelectric and straintemperature stability (the variations are below 3% under 30-100 ℃) areachieved, showing great property advantage compared with previous reports.Different from the compositionally graded composite ceramic design, theHo doping can not only increase orthorhombic-tetragonal phase transitiontemperature (T_(O-T)) and then create the condition for the formation of successivephase transition, but also stabilize the oriented domain state. Therefore,the excellent temperature stability of both piezoelectricity and strain can beattributed to the multistep phase transition induced by the multilayer design,the fine regulation of T_(O-T) interval by the optimization of lamination combination,and the stabilized polarization induced by Ho doping. The new strategyfor solving both piezoelectric and strain temperature sensitivity can furtherpromote the commercial application of potassium sodium niobate-basedlead-free piezoelectric ceramics.