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A thermodynamic model is established to investigate the effects of internal stress in PbZrO3 (PZ) antiferroelectric (AFE) film on the barocaloric effect (BCE), electrocaloric effect (ECE), and energy storage properties. It is found that the internal stress can change the phase transition behaviors and free energy barriers among AFE, ferroelectric (FE), and paraelectric (PE) phases. For the BCE, it occurs only in the FE phase induced by stress or temperature. Under a certain temperature, the optimized negative and positive ECE can be obtained by controlling the internal stress and electric field. In addition, the switching electric field of the AFE→FE phase transition increases and causes a larger recoverable energy density with decreasing tensile stress. These results are analyzed and explained by tricritical points (3 cp) with different stresses, temperatures, and electric fields. Therefore, this thermodynamic model provides an effective route to optimize the BCE, ECE, and energy storage properties of PZ films. [ABSTRACT FROM AUTHOR]

Pb0.99Nb0.02(Zr0.85Sn0.13Ti0.02)O3 (PNZST) antiferroelectric (AFE) thick films are successfully deposited on silicon‐based Pt and LaNiO3 electrodes by a sol‐gel method. The coexistence of ferroelectric (FE) and AFE phases are revealed in PNZST films by XRD, electric‐induced hysteresis loops, dielectric, and leakage current properties. Comparing with PNZST/Pt film, larger recoverable energy density and efficiency are obtained in PNZST/LaNiO3 film due to the lower FE phase proportion. It is analyzed and demonstrated by a thermodynamic model of AFE and FE coexistence system. In addition, the fatigue behaviors of both AFE films are also affected by the proportion of the coexisting FE phase. PNZST/LaNiO3 film exhibits good fatigue resistance on energy storage even after 1010 switching cycles, which is attractive to pulsed power applications. [ABSTRACT FROM AUTHOR]