Electrocaloric behavior and piezoelectric effect in relaxor NaNbO3‐based ceramics. Issue 5 (5th October 2018) - Tao, Hong
Abstract: We firstly reported the electrocaloric properties in relaxor (1− x − y )NaNbO3 – y BaTiO3 – x CaZrO3 ceramics, and high electrocaloric effect (∆ T ~0.451 K and∣∆ T /∆ E ∣~0.282 Km/MV) can be realized in the ceramics ( x = 0.04 and y = 0.10) under low temperature and low electric field. Relaxor behavior of NaNbO3 ceramics can be found by doping both BaTiO3 and CaZrO3 . In addition, optimized piezoelectric effects ( d 33 ~235 pC/N and d 33 * ~230 pm/V) can be observed in the ceramics ( x = 0.04 and y = 0.10) due to the involved morphotropic phase boundary (MPB). Excellent piezoelectric effect (ie, d 33 ~330 pm/V at 41°C, and d 33 *~332 pm/V at 60°C) can be found because of the characteristics of MPB. Good temperature reliability of piezoelectric effect can be shown because of both MPB and relaxor behavior. We believe that the ceramics with high electrocaloric effect and good piezoelectric effect can be considered as one of the most promising lead‐free materials for piezoelectric devices. Abstract : Significant MPB and relaxor behavior can be revealed in NaNbO3 ceramics with BaTiO3 and CaZrO3 modified. Sequentially, the giant electrocaloric effect (?T ~ 0.451 K) and high piezoelectric effect (d33 ~ 330 pm/V) as well as good temperature stability were realized in the ceramics benefit by the MPB and relaxor behavior. It can be believed that this result can partly promote the investigation of lead‐free cermics.