Energy storage and piezoelectric properties of lead‐free SrTiO3-modified 0.965Bi0.5Na0.5TiO3–0.035BaTiO3 ceramics

This manuscript reports the synthesis and piezoelectric properties of strontium titanate, SrTiO3-modified bismuth sodium titanate-barium titanate, 0.965Bi0.5Na0.5TiO3–0.035BaTiO3, (BNBT-xST, x = 0.00−0.30) ceramics produced by facile low temperature sol–gel and hydrothermal methods. Close inspection of the X-ray diffraction profile through Rietveld refinement indicates ST modification in BNBT leads to a phase transition from the dominant rhombohedral phase to a single tetragonal phase. This structural transition leads to enhancement of electromechanical and energy storage properties. A large dynamic piezoelectric coefficient (d*33 = 350 pC/V) was observed for BNBT-0.1ST sample. High energy storage density (Wrec = 0.37) and large energy storage efficiency (η = 75%) were observed at 75 °C for the BNBT-0.3ST sample. The energy storage response of the tunable ferrorelectric ceramics suggests their possible use for high-performance dielectric capacitor applications.