Thermodynamic Analysis of Stress‐Mediated Barocaloric Effect, Electrocaloric Effect, and Energy Storage of PbZrO3 Antiferroelectric Film

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. A stress‐mediated thermodynamic model of PbZrO3 antiferroelectric film is established by Ginzburg–Landau–Devonshire (GLD) phenomenology theory based on the Kittel model. The internal stress changes the phase transition behaviors and free energy barriers, which could be used to optimize the barocaloric effect (BCE), electrocaloric effect (ECE), and energy storage properties of PbZrO3 film.