Effect of sintering time on microstructure, relaxor behavior and energy storage properties of lead-free Sr2NaNb5O15 (SNN) ceramics
Ceramics International, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.ceramint.2026.07.470
- Dergi Adı: Ceramics International
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, Compendex, INSPEC, Academic Search Ultimate (EBSCO), Engineering Source (EBSCO)
- Anahtar Kelimeler: Dielectric properties, Ferroelectric characteristics, Lead-free ceramics, Sintering time, Tetragonal tungsten bronze
- Gazi Üniversitesi Adresli: Evet
Özet
Optimizing sintering parameters is crucial for enhancing performance in practical applications, including dielectric capacitors, ferroelectric devices, and energy storage systems. Despite the progress made in lead-free Tetragonal Tungsten Bronze (TTB) ceramics, the interrelation between the sintering time and the subsequent balance of functional properties remains insufficiently explored. In this work, Sr2NaNb5O15 (SNN) ceramics were fabricated using sintering times ranging from 3 to 10 h. Their structural, morphological, and electrical characteristics were investigated. All the samples appear to be single phase, and their structure is refined in the tetragonal P4bm space group. Sintering time has a great effect on the dielectric behavior with maximum permittivity (εm = 1728) achieved for ceramic sintered for 4 h. Additionally, all samples reveal low dielectric losses (tanδ ≤5 %). Furthermore, optimized recoverable energy storage density (Wrec = 0.40 J/cm3) and efficiency (η = 84.3 %) were observed for ceramics sintered for 5 h. With increasing temperature, a slight decrease in Wrec is observed across a wide range of temperatures (RT to 140 °C), as η remained above 93.7 %. Although the Wrec value is relatively low, the present work demonstrates a systematic sintering time-dependent evolution of lead-free TTB SNN ceramics, highlighting their potential for high-temperature electronic applications due to stable ferroelectric behavior, high permittivity, and low tanδ.