Achieving Giant Piezoelectricity and High Property Uniformity Simultaneously in a Relaxor Ferroelectric Crystal through Rare‐Earth Element Doping
Yangbin Liu, Qian Li, Liao Qiao, Zhuo Xu, Fei Li
Abstract
Abstract The low uniformity in properties of relaxor ferroelectric crystals is a long‐standing issue in the ferroelectric community, which limits the available volume of the entire crystal boule. The aim of this study is to develop a relaxor ferroelectric crystal with improved property uniformity and excellent piezoelectricity. To this end, Pb(In 1/2 Nb 1/2 )O 3 –Pb(Mg 1/3 Nb 2/3 )O 3 –PbTiO 3 is doped with Nd 2 O 3 (Nd–PIN–PMN–PT) to improve the crystal performance. Along the crystal boule, the piezoelectric coefficient d 33 varies from 2800 to 3500 pC N −1 , and the dielectric constant ranges from 8400 to 9800, with variations of 25% and 16%, respectively. Such high property uniformity results in over 75% available volume of the crystal boule, compared to 30–50% for undoped crystals grown by Bridgman method. At the electric field of 1 kV cm −1 , the converse piezoelectric response is up to 4780 pm V −1 . In addition, its Curie temperature ( T C ) and coercive field ( E C ) are above 150 °C and 3 kV cm −1 , respectively. Compared with Pb(Mg 1/3 Nb 2/3 )O 3 –PbTiO 3 crystal ( d 33 : 1500 pC N −1 , T C : 135 °C, E C : 2.3 kV cm −1 ), the larger piezoelectricity, the higher T C and E C , and improved uniformity make Nd–PIN–PMN–PT crystals promising candidates for advanced piezoelectric applications.