Research Projects

Dielectric capacitors and electrocaloric cooling/refrigeration devices are promising and sustainable alternatives for energy storage and low temperature ambience production. Lead-based antiferroelectrics offer promising energy storage and electrocaloric performance, but their use is limited by their toxic effects on human health and the environment. Lead-free ferroelectrics offer potential but suffer from high remnant polarization, loss of recoverable work, and low electrocaloric response. Relaxor-ferroelectrics (RFE) are a promising material with desirable energy storage characteristics, such as high saturation polarization, moderate breakdown strength, and low remanent polarization. However, their performance is not comparable to lead-based anti-ferroelectric ceramics. This project aims to improve the energy storage performance and electrocaloric response of RFE perovskite ceramics using the high entropy concept. High entropy ceramics have shown superior mechanical, catalytic, thermal, and tribological properties over conventional ceramics. Recent studies have reported high energy storage performance of high entropy A-site substituted RFE perovskite ceramics, but the effect of B-site and combined A/B-sites substitution on these ceramics for energy storage applications is not yet reported. Only three high entropy A-site substituted RFE perovskite ceramics have shown high electrocaloric response. The project proposes lead-free high entropy A-site, B-site, and combined A-/B-site substituted RFE perovskite ceramics to achieve high energy storage performance and large electrocaloric response.