High Energy Storage Performance of All-Inorganic Flexible Antiferroelectric-Insulator Multilayered Thin Films

With the increasingly high requirements for wearable and flexible devices, traditional inorganic capacitors cannot meet the flexible demand of next-generation electronic devices. In this work, the energy storage property of all-inorganic flexible films has been systematically studied. PbZrO₃ (PZO) and Al₂O₃ (AO) are selected as the antiferroelectric layer and insulating layer, respectively. The heterostructured films are prepared on the fluorphlogopite (F-Mica) substrate by chemical solution deposition. The microstructure, polarization behavior, and energy storage performances are investigated. The results demonstrate that the AO/PZO/AO/PZO/AO (APAPA) multilayered thin film possesses a greatly improved energy storage density (W_rec) of 28.1 J/cm³ with an excellent energy storage efficiency (η) of 80.1%, which is ascribed to the enhanced breakdown strength and large difference in polarization. Furthermore, the capacitive films exhibit good stability under a wide working temperature range of 25-140 °C and an electric fatigue endurance of 10⁷ cycles. Besides, the energy storage performances are almost unchanged after 10⁴ bending cycles, demonstrating an excellent mechanical bending endurance. This work sheds light on the preparation technology and improvement of the dielectric energy storage performance for all-inorganic flexible multilayered thin films.