Electrocaloric response of KNbO3 from a first-principles effective Hamiltonian

Coexistence of Large Negative and Positive Electrocaloric Effects and Energy Storage Performance in LiNbO3 Doped K0.5Na0.5NbO3 Nanocrystalline Ceramics

“…Alkaline-based materials such as K 0.5 Na 0.5 NbO 3 (KNN), solid solution of NaNbO 3 (antiferroelectric), and KNbO 3 (ferroelectric) have shown high potential for an EC refrigerator. KNN is a good piezoelectric material and has good electromechanical responses along with the excellent electrical behavior, e.g., high dielectric constant and high Curie temperature ( T C ). − A result based on simulation for KNN stated about high remanent polarization and the low coercive field, which are much more beneficial for high ECE. The larger value of Δ T can be achieved at a high field with the higher breakdown field in the thin film and nanostructures, but they display lower electrocaloric efficiency (Δ T /Δ E ) and cooling capacity.…”

Giant electrocaloric and energy storage performance of [(K0.5Na0.5)NbO3](1−x)-[LiSbO3] x nanocrystalline ceramics

“…There had been a various report on the mentioned materials, but achieved EC temperature change (Δ T ) is very less. It has been simulated for high polarization change, which is the key factor for ECE; associated with K 0.5 Na 0.5 NbO 3 (KNN) based ceramics 27 but experimentally there is no report for high positive ECE value so far. It is a ferroelectric material with the perovskite structure which exhibits temperature-dependent spontaneous polarization and possess giant ECE and also the best candidate for solid-state cooling 28 , 29 .…”