BST-BZT叠层弛豫铁电陶瓷的制备及其电卡效应研究OA

Lead-free relaxor ferroelectric based laminated ceramics are one of the important choices for environmentally friendly electrocaloric solid-state refrigeration devices.In this study,the x(Ba0.65Sr0.35)TiO3-(1-x)Ba(Zr0.2Ti0.8)O3(0.8BST-0.2BZT,x=0.8;0.2BST-0.8BZT,x=0.2)thick films were prepared via tape-casting process,and the laminated ceramics of 0.8BST-0.2BZT/0.2BST-0.8BZT/0.8BST-0.2BZT were constructed using a stacking process.Meanwhile,0.8BST-0.2BST and 0.2BST-0.8BZT ceramics were prepared by solid-state reaction for comparison,and their microstructure,dielectric temperature characteristics,ferroelectricity,and electrocaloric effects were studied.The research results indicate that laminated ceramics have more pronounced dielectric relaxation characteristics and larger polarization difference(Ps-Pr).The significant electrocaloric effect(ΔT=0.9 K)and wide broad working temperature span(Tspan=50℃)of laminated ceramics were measured using indirect measurements under an electric field of 50 kV/cm.This result is further verified by direct measurements under 25 kV/cm,and significant electrocaloric temperature change(ΔT=0.25 K)and Tspan(>45℃)were observed.This work demonstrates that the developed laminated ceramics possess excellent temperature stability and wide temperature range adaptability,showing great potential for electrocaloric cooling applications.