Paper EH-ThM4
Lead-free Epitaxial Ferroelectric Heterostructures for Energy Storage and Harvesting Applications

Thursday, December 6, 2018, 9:00 am, Room Naupaka Salon 6-7

Fast and rapid depletion of natural resources such as fossil fuel and coal is driving researchers to focus continuously on the development of new technologies and exotic materials having high energy density and efficiency for both harvesting and storage of clean and green energy. In United States, nearly 68% of the primary energy produced is wasted as a heat each year. Energy harvesting for low power electronic devices using ferroelectric materials is one of the emerging areas of research because they possess excellent piezoelectric and pyroelectric coefficients. These materials are unique as they only sense time dependent temperature change to generate electric power. Temperature change can be obtained through different ambient sources such as waste-heat, solar radiation etc. We have grown lead free BaZr_0.2Ti_0.8O₃ (BZT)/ Ba_0.7Ca_0.3TiO₃ (BCT) multi-layer hetero structures and studied the structural, dielectric, ferroelectric, pyroelectric and energy density characteristics. The BZT/BCT multiplayer epitaxial hetero-structures were grown on La Sr MnO (LSMO) buffered SrTiO (STO) single crystal substrate by optimized pulsed laser deposition technique. The ferroelectric phase transitions have been probed above room temperature with relaxor behavior. These heterostructures show large polarization change and high energy density characteristics due to interface effect even at low applied field and small temperature fluctuation which may be useful for both high energy storage density and thermal harvesting applications.