Phase Structure Tuned Electrocaloric Effect and Pyroelectric Energy Harvesting Performance of (Pb0.97La0.02)(Zr,Sn,Ti)O3 Antiferroelectric Thick Films

In the present work, (100)-oriented (PB0.97La0.02)(Zr0.95-xSnxTi0.05)O-3 antiferroelectric thick films with x = 0.08, 0.20, and 0.38 were successfully fabricated. These compositions are located in the orthorhombic phase region, the morphotropic phase boundary (MPB), and the tetragonal phase region, respectively. The effects of their phase structure on the electrocaloric effect and the pyroelectric energy harvesting behavior were investigated. A considerable temperature reduction of Delta T = 13, 33, and 27 degrees C, due to the ferroelectric antiferroelectric phase transition, was obtained at 25 degrees C in these thick films for x = 0.08, 0.20, and 0.38, respectively. Moreover, a huge harvested energy density per cycle of W = 3.6, 6.8, and 4.0 J/cm(3) was also realized under the experimental condition in the thick films with x = 0.08, 0.20, and 0.38, respectively. These results indicated that both the cooling performance and the pyroelectric energy harvesting in antiferroelectrics could be optimized by the proper phase structure control.