Simultaneous enhancement of piezoelectricity and mechanical quality factor in relaxor-ferroelectric crystals via defect engineering

Abstract

Both high piezoelectric response and mechanical quality factors (Qm) are essential for high-power applications of ferroelectric materials. However, there always exists a trade-off between these two parameters, which makes the collaborative optimization to be a great challenge. Here, a hardening effect is achieved via defect engineering in the acceptor-doped PbTiO3-relaxor-ferroelectric crystals by alternating current poling technique. It is found that under the AC electric field, the defect diploes are decoupled into isolated charged defects and accumulate at domain walls, which strongly pin domain wall motions while promoting ferroelectric dipole dynamics. Consequently, simultaneous enhancement of d33 and Qm is realized, where d33 increases by 16% and Qm enhances by 51%. This work offers an efficient and convenient approach in material design for practical high-power piezoelectric applications.