Comparative study of piezoelectric response and energy-storage performance in normal ferroelectric, antiferroelectric and relaxor-ferroelectric thin films

The energy-storage performance and piezoelectric properties were determined for epitaxial antiferroelectric (AFE) PbZrO₃ (PZ), ferroelectric (FE) PbZr_0.52Ti_0.48O₃ (PZT), and relaxor ferroelectric (RFE) Pb_0.9La_0.1Zr_0.52Ti_0.48O₃ (PLZT) thin films that were deposited on to SrTiO₃ buffered Si substrates. The films were investigated by directly measuring the polarization hysteresis loops and piezoelectric strain curves. The square polarization loop with a high remanent polarization and a large piezoelectric coefficient obtained in PZT thin films allow them to be useful for various applications in ferroelectric field effect transistors and/or in MEMS actuators. Meanwhile, there is a jump of about 0.9% in the strain curve of PZ thin films around the field-induced AFE-FE phase transition, which is useful in digital displacement transducers due to a good ON/OFF strain state. The large recoverable energy-storage density, excellent energy-storage efficiency, and low strain hysteresis due to a slim hysteresis loop combine to make PLZT thin films as a potential candidate for a broad range of applications from energy storage to nano-positioning precision systems.