Large electrocaloric effect in \({\text{BiScO}}_{3}\) doped \({\text{K}}_{{0.5}}\) \({\text{Na}}_{{0.5}}\) \({\text{NbO}}_{3}\) ceramics

Exploring an electrocaloric (EC) material with a large electrocaloric effect (ECE) value is of high interest and importance to realize a solid-state cooling solution. We have investigated the electrocaloric performance and energy storage density in lead-free (1-x) \(\text {K}_{0.5}\) ${\text{K}}_{0.5}$ \(\text {Na}_{0.5}\) ${\text{Na}}_{0.5}$ \(\text {NbO}_{3}\) ${\text{NbO}}_3$ -x \(\text {BiScO}_{3}\) ${\text{BiScO}}_3$ (KNN-xBS) ferroelectric ceramics. The KNN-xBS (x = 0.01, 0.02, 0.03, and 0.10) ceramics were synthesized by the typical solid-state route and ECE was examined by an indirect method based on Maxwell’s relations. The maximum value of ECE has obtained 0.61 K at 428 K for 60 kV/cm applied field, and the recoverable energy density has 0.57 J/ \(\text {cm}^{3}\) ${\text{cm}}^3$ for x = 0.01 ceramics. The obtained positive ECE has a larger value among different lead-free ceramics. The \(\text {BiScO}_{3}\) ${\text{BiScO}}_3$ doped \(\text {K}_{0.5}\) ${\text{K}}_{0.5}$ \(\text {Na}_{0.5}\) ${\text{Na}}_{0.5}$ \(\text {NbO}_{3}\) ${\text{NbO}}_3$ ceramics have presented enormous potential in solid-state cooling technology for a cleaner environment.