Promising Lead-Free BiFeO3-BaTiO3 Ferroelectric Ceramics: Optimization Strategies and Diverse Device Applications

Bismuth ferrite-barium titanate (BF-BT) ceramics show promise for high-temperature device applications, potentially supplanting lead-based counterparts. Recent studies have focused on optimizing their functional properties through various synthesis methods, including sol–gel, spark plasma sintering, and microwave sintering, to tailor their microstructure and enhance the overall performance for various applications. This review focuses on optimization strategies such as synthesis methods, heat treatment, doping, and domain engineering. Challenges in the current research landscape include a deeper understanding of the mechanisms involved in dopant-induced changes, especially concerning the interplay between crystal structure, microstructure, and resulting properties. The enduring stability of certain properties, notably piezoelectricity, under various conditions, such as elevated temperatures, remains an area of interest. Addressing issues related to processing techniques, scalability, and the environmental impact of manufacturing processes is also paramount. Future research is poised to explore novel applications and integration challenges of BF-BT ceramics into advanced electronic and electromechanical devices, such as energy storage capacitors, high-temperature accelerometers and multilayer actuators, magnetoelectric coupling, piezocatalysis devices, and BF-BT/PVDF composite-based devices, while also emphasizing the crucial need for device characterization.