Significantly improved Curie temperature and electrical properties of Sm-doped Pb(NiNb)O-PbZrO-PbTiO by introducing Pb(MgNb)O.

Pb(NiNb)O-PbZrO-PbTiO (PNN-PZ-PT) is one of the typical relaxor-PT piezoelectric systems. In order to further improve its Curie temperature () and piezoelectric properties, nominal Pb(MgNb)O (PMN) is introduced into 2mol% Sm-doped 0.36PNN-0.28PZ-0.36PT to form a (0.36 - )PNN-PMN-0.28PZ-0.36PT:0.02Sm ( = 0-0.24) quaternary solid solution. The phase, microstructure, domain structure, and electrical properties of the solid solution ceramics were investigated systematically. All the samples exhibit a single phase perovskite structure and are situated around the rhombohedral-tetragonal morphotropic phase boundary. With increasing , the increases gradually, while the piezoelectric coefficient increases initially and decreases subsequently, reaching a peak value of 725 pC N at around = 0.15. In particular, this optimal composition illustrates high performance with = 176 °C, planar electromechanical coupling factor = 0.63, remanent polarization = 30 μC cm, and coercive field = 8.9 kV cm. This study illustrates the viability of incorporating PMN into PNN-PZ-PT to optimize the comprehensive electrical properties, potentially offering a valuable guide for developing high performance relaxor-PT materials.