Low-temperature fabrication of BTO-based relaxor ferroelectric thick films with multi-layered architecture

Screen-printed BTO-based ceramic films conventionally suffer from issues such as high sintering temperatures incompatible with Ag electrodes, poor temperature stability, high porosity, and inferior electrical properties. In this study, the 0.3(Na_0.5Bi_0.5)TiO₃-0.7(Ba_0.9Sr_0.1)(Ti_0.8Zr_0.2)O₃ (0.3NBT-0.1Sr-0.2Zr) ferroelectric ceramic films were fabricated on alumina substrates with Ag electrodes via screen printing, followed by sintering at a maximum temperature of 900 °C. The effects of the lead-free glass additive and "sandwich" structure on the microstructure, dielectric properties, and energy storage properties of the ceramic films were systematically investigated. The optimized electrical properties of the multilayer ceramic thick film were achieved as follows: a dielectric constant of 585, a dielectric loss of 0.033, a temperature coefficient of dielectric constant of -39 ppm °C^-1 (20-120 °C), a breakdown strength of 405 kV cm^-1, an energy storage density of 1.65 J cm^-3, a remanent polarization of 2.34 µC cm^-2, and an energy storage efficiency of 74.3%. Low-temperature sintering of BaTiO₃-based relaxor ferroelectric ceramic films with high energy storage properties was successfully achieved via screen printing.