Dielectric and Improved Energy-Storage Properties in A-Site Nd3+ Doped Lead-Free 0.88NaNbO3-0.12Sr0.7Bi0.2TiO3 Ceramics

• Published in: Integrated ferroelectrics Vol. 238; no. 1; pp. 160 - 172
• Main Authors: Premwichit, Pathit, Jaitha, Natthakan, Gupta, Sanu Kumar, Cann, David P., Prasertpalichat, Sasipohn
• Format: Journal Article
• Language: English
• Published: Philadelphia Taylor & Francis 13.10.2023; Taylor & Francis Ltd
• Subjects: Antiferroelectricity; Ceramics; Composition; Density; Dielectric properties; Doping; Efficiency; Electric fields; Energy storage; energy storage properties; Lead free; Lead-free ceramics; Mixed oxides; NaNbO; Phase transitions; Room temperature; Sodium compounds; Temperature; Transition temperature
• ISSN: 1058-4587; 1607-8489
• DOI: 10.1080/10584587.2023.2234564

Sodium niobate (NaNbO 3 )-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, 0.88NaNbO 3 -0.12Sr 0.7 Bi 0.2 TiO 3 ceramics doped with Nd 3+ (i.e., 0.88Na 1-3 x Nd x NbO 3 -0.12Sr 0.7 Bi 0.2 TiO 3 ) 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 Nd 3+ doping content, the antiferroelectric P (Pbma) phase to R (Pnma) phase transition temperature (T P-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 (W rec ) and efficiency (η) with an increasing amount of Nd 3+ doping level. The maximum recoverable energy storage density (W rec = 0.54 J/cm 3 ) 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.