Large Electrocaloric Effect in Lead-Free (Ba0.85Ca0.15)(Zr0.1Ti0.9)O3 Ceramics Prepared via Citrate Route

Abstract

Abstract:The 1 wt % Li-doped (Ba 0.85 Ca 0.15 )(Zr 0.1 Ti 0.9 )O 3 (BCZT-Li) ceramics prepared by the citrate method exhibit improved phase purity, densification and electrical properties, which provide prospective possibility to develop high-performance electrocaloric materials. The electrocaloric effect was evaluated by phenomenological method, and the BCZT-Li ceramics present large electrocaloric temperature change ∆T, especially large electrocaloric responsibility ξ = ∆T max /∆E max , which can be comparable to the largest values reported in the lead-free piezoelectric ceramics. The excellent electrocaloric effect is considered as correlating with the coexistence of polymorphic ferroelectric phases, which are detected by the Raman spectroscopy. The large ξ value accompanied by decreased Curie temperature (around 73 • C) of the BCZT-Li ceramics prepared by the citrate method presents potential applications as the next-generation solid-state cooling devices.

Nd3+ and Nb5+ Co‐Substitution Inducing a Large Electrocaloric Response in Na0.5Bi0.5TiO3 Lead‐Free Ceramics

“…Here ρ is the density of the ceramics is noted 5.9 g cm −3 for NBNT‐Nb‐0 and 5.82 g cm −3 for NBNT‐Nb‐1with the help of Archimedes method, respectively. The observed values are found to be very close to the pure NBT based ceramics . The electrocaloric temperature variation (Δ T ) as a function of temperature for both ceramics, obtained with varies in electric fields as shown in Figure a,b.…”

Thermally-stable high energy storage performances and large electrocaloric effect over a broad temperature span in lead-free BCZT ceramic

“…In contrast, very slim loops appeared, corresponding to the existence of ferroelectric clusters or residual polar nanoregions (PNR), [58][59][60] oen attributed to the relaxor behavior. 29 The temperaturedependence of the energy storage performances of the BCZT ceramic at 60 kV cm À1 is presented in Fig. 6b.…”

“…26 The electrocaloric effect (ECE) in BCZT relaxor ferroelectric ceramics has been widely investigated. 15,[27][28][29][30][31] Kaddoussi et al 12 studied the ECE in Ba 0.85 Ca 0.15 Zr 0.10 Ti 0.90 O 3 indirectly using the Maxwell relation at 8 kV cm À1 , and found a low electrocaloric temperature change (DT) of 0.152 K. Using the same approach, Ben Abdessalem et al 28 obtained DT ¼ 0.565 K at 30 kV cm À1 . Zhou et al 32 studied the compositional dependence of the electrocaloric effect in lead-free (1 À x)Ba(Zr 0.20 Ti 0.80 )O 3x(Ba 0.70 Ca 0.30 )TiO 3 ceramics under a moderate electric eld of 28 kV cm À1 , and reported a high ECE response of 0.56 K at x ¼ 0.6.…”

Thermal-stability of the enhanced piezoelectric, energy storage and electrocaloric properties of a lead-free BCZT ceramic

“…For eco-friendly solid-state refrigeration, BCZT ceramic demonstrated enhanced electrocaloric properties. 13,[16][17][18][19][20][21] Zhou et al 18 investigated the electrocaloric effect (ECE) in lead-free (1 À x)BZT-xBCT system under a moderate electric eld of 28 kV cm À1 and reported high ECE response of 0.56 K at x ¼ 0.6. In addition, Ben Abdessalem et al 22 studied the electrocaloric effect (ECE) in BCZT indirectly using Maxwell relation under 30 kV cm À1 and obtained DT ¼ 0.565 K around T C ¼ 119 C. Besides, Hanani et al 11 reported a signicant electrocaloric temperature change (DT) of 1.479 K with remarkable refrigerant capacity (RC) of 140.33 J kg À1 , and a high coefficient of performance (COP ¼ input power/output cooling power) 23 of 6.29 under 55 kV cm À1 .…”