Preparation and electrical properties of MoO3-modified SrBi2Nb2O9-based lead-free piezoelectric ceramics

Lead-free piezoelectric ceramics, SrBi2(Nb1-xMox)(2)O-9 (SBNM-x), were prepared by a conventional solid-state reaction method. The crystal structure, microstructure and electrical properties were systematically investigated. The X-ray diffraction analysis suggested that the substitution formed layered perovskite structure. Plate-like morphology of the grains which is characteristic for layer-structure Aurivillius compounds was clearly observed for all the samples. The excellent electrical properties (e.g., d(33) similar to 18 pC/N, 2P(r)similar to 20.34 mu C/cm(2)) and a high Curie temperature (e.g., T-c similar to 458 degrees C) are simultaneously obtained in the ceramics with x = 0.12. Additionally, thermal annealing studies indicated that piezoelectric constant (d(33)) of SBNM-0.12 ceramic remains almost unchanged (16 pC/N, only decrease by 12%) at temperatures below 400 degrees C, demonstrating that the Mo-modified SBN-based ceramics are the promising candidates for high-temperature applications. (C) 2016 Published by Elsevier B.V.