New trends on the synthesis of piezoelectric lead free materials

Oral presentation given at the Piezo 2017: Electroceramics for End Users IX, held in Cercedilla (Region of Madrid, Spain), on February 19-22th, 2017.On the search for lead free materials with piezoelectric properties, the synthesis methods play a determinant role on their final properties. Synthesis and processing of these materials is not quite simple and some challenges are yet to be faced. Stoichiometric control, softer synthesis conditions, adequate grain size, ferroelectric domain size and distribution, sintering conditions and scalability for industrial transfer. The most widely used piezoelectric is the PZT, but during the last two decades, due to environmental rules, the lead free materials have been intensely studied such as the featuring families with related perovskite structure: BaTiO3 (BT), Ba1-xCaxTi1-yZryO3 (BCZT), (Bi0.5Na0.5)TiO3 (BNT) and (K0.5Na0.5)NbO3 (KNN). New trends on these methods involve the search of the most eco-friendly chemical way. In this work several routes to obtain these materials and their solid solutions with different cations are discussed