Crystal growth of PMN-PT for energy harvesting applications

Abstract

The harvesting of mechanical energy has been investigated extensively over the last decade. This type of harvesting is widely utilized in the applications of vibration-based energy harvester. Energy harvesting using piezoelectric materials is an efficient system due to high voltage output and power intensity in addition to its suitability in autonomous electric devices. One of the most promising piezoelectric materials is the relaxor ferroelectric PMN-PT: Pb(Mg1/3Nb2/3)O3-PbTiO3 single crystal. The exceptionally high values of the electromechanical coupling factor (K33), piezoelectric constant (d33), thickness coupling coefficient (Kt), and dielectric constant with low loss have made it a unique candidate to harvest energy. However, the growth of PMN-PT single crystals presents many challenges. Among those challenges is the decomposition of PbO into Pb and O2, which in turn may eventually ruin the crucible, even during the first growth. In this paper, an exhibition of several PMN-PT growth attempts in different crucible types and shapes are demonstrated. Based on the experimental results, the analyses of XRD, Kt, dielectric constant, and Glow Discharge Mass Spectroscopy are discussed.