Dielectric and Improved Energy-Storage Properties in A-Site Nd 3+ Doped Lead-Free 0.88NaNbO 3 -0.12Sr 0.7 Bi 0.2 TiO 3 Ceramics

AbstractSodium niobate (NaNbO3)-based antiferroelectric (AFE) ceramics have received significant attention for energy storage applications because of their good performance, low cost, and nontoxicity. However, the existence of the antiferroelectric P phase at room temperature causes large hysteresis, resulting in reduced energy storage efficiency. In this study, 0.88NaNbO3–0.12Sr0.7Bi0.2TiO3 ceramics doped with Nd3+ (i.e., 0.88Na1-3xNdxNbO3-0.12Sr0.7Bi0.2TiO3) at x = 0.0 − 0.025 were prepared via conventional solid-state mixed oxide route. The XRD data showed that all samples exhibited an orthorhombic structure. With increasing Nd3+ doping content, the antiferroelectric P (Pbma) phase to R (Pnma) phase transition temperature (TP-R) shifted to lower temperatures. Consistent with the dielectric properties, a transition to a relaxor-like slim P-E loop indicative of an AFE R phase was observed at the composition x ≥ 0.01. This led to an increase in both the recoverable energy-storage density (Wrec) and efficiency (η) with an increasing amount of Nd3+ doping level. The maximum recoverable energy storage density (Wrec = 0.54 J/cm3) and high energy storage efficiency (η = 93%) were observed at x = 0.025 under an applied electric field of 100 kV/cm. In addition, the optimum composition at x = 0.025 also exhibited excellent temperature stability from 25 °C to 150 °C. This research demonstrates that the NN–SBT–xNd system has the potential for use for high-energy-density pulsed power capacitor applications.Keywords: Lead-free ceramicsNaNbO3energy storage properties Disclosure StatementNo potential conflict of interest was reported by the author(s).Additional informationFundingThis work was financially supported by The National Science, Research and Innovation Fund (NSRF) through Naresuan University (R2565B059).