High performance lead (Pb)-free piezoelectric ceramics with excellent piezoelectric properties is in great demand for sensor and actuator applications. Barium zirconate titanate-barium calcium titanate [xBZT -(1 - x)BCT] (x = 0.5) is one such lead free system, which exhibits high piezoelectric properties similar to lead zirconate titanate (PZT). In this study we report the synthesis and characterization of this lead free [xBZT-(1 - x)BCT] (x = 0.5) via wet chemical sol-gel method. Calcination of the BZT-BCT precursor only at 1000 degrees C (against 1300 degrees C reported in the literature) for 4 h resulted in formation of single phase nanoparticles (<50 nm) as confirmed by X-ray diffraction (XRD) and transmission electron microscopy (TEM) studies. Highly dense and homogenous microstructure with 95% of the theoretical density was obtained by solid-state sintering of the green pellets at 1550 degrees C. Remanent polarization (Pr) of 11.55 mu C/cm(2) and relative permittivity of 20,020 at the Curie temperature of 95 degrees C were obtained. Electrically poled BZT-BCT ceramics samples exhibited high piezoelectric charge coefficients, d(33) similar to 530 pC/N, d(33)* similar to 942 pm/V, large electromechanical coupling coefficient k(p) similar to 0.45 and a large strain of 0.15%, which are comparable to those of lead based piezoelectric ceramics. The excellent piezoelectric properties of this sol-gel derived BZT-BCT system has been analyzed and correlated to its structure in this report. (C) 2014 Elsevier B.V. All rights reserved.

Lead-free piezoelectric ceramics barium zirconate titanate–barium calcium titanate [(1 − x)BZT − xBCT] (x = 0.5) have been prepared by sol–gel synthesis. The structure and piezoelectric properties were investigated for the given BZT–BCT system. The as-synthesized powders were calcined at 1,000 °C and pressed into cylindrical pellets. Solid-state sintering was carried at temperature of 1,550 °C for 2 h which resulted in a complete perovskite structure. Hysteresis loops were obtained for the BZT–BCT sintered pellets indicating its ferroelectric nature. The bulk ceramic samples were subjected to electrical poling and the piezoelectric properties were measured. The effect of microstructure on the piezoelectric properties of BZT–BCT ceramics is correlated for the given composition is discussed in this paper.

Lead free piezoelectric ceramics 'Barium calcium zirconium titanate (Ba0.85Ca0.15)(Zr0.9Ti0.1)O-3 have been prepared by sol-gel synthesis method. The structure and piezoelectric properties were investigated for the given BCZT system. X-ray diffraction (XRD) and transmission electron microscope (TEM) studies confirmed the formation of single phase BCZT nanoparticles (<50nm). The calcined and compacted powders sintered at 1550 degrees C resulted in a complete perovskite structure. BCZT sample showed a high remnant polarization of 11.55 mu C/cm(2) and a low coercive field (E-c) of 0.166 kV/cm. A high piezoelectric co-efficient of d(33)similar to 490 pC/N was obtained for the electrically poled sample. The study of microstructure on its piezoelectric properties of BCZT ceramics is discussed in this paper.