Smart Materials for Energy Harvesting, Energy Storage, and Energy Efficient Solid-State Electronic Refrigeration

The new emerging fields of MEMS-based energy harvesting from piezoelectric materials, lead to the development of solid-state electrostatic energy storage for better power/energy distribution for renewable energy and the solid-state electrocaloric cooling for low energy and hazard free refrigeration. Among them it is being reported that on application of 8.693 TPas⁻¹ oscillated stress generates 10 Vs⁻¹ oscillated voltage in 300 nm 0.75PMN–0.15PT thin films where 22 Jcc⁻¹ s⁻¹ of oscillated energy density can be harvested on application of 15 TPas⁻¹ oscillated pressure upon 500 nm thin film of same material. It is also described that La modified antiferroelectric PbZrO₃ (PZ) thin films are the potential materials that can achieve the high energy density storage density in the order of 103 J/kg. Though PZT-based antiferroelectric cooling triggered the research on the materials for electrocaloric cooling by the amount of 12 K adiabatic decrease in temperature on withdrawal of electric field, the decrease in temperature by 11.4 K in pure PZ and by 31 K in 0.63PMN–0.37PT thin film are found commendable.