Enhanced pyroelectric performance in Na0.5Bi0.5TiO3-xNa0.5Bi4.5Ti4O15 lead-free ferroelectric ceramics via composition and microstructure engineering. (1st October 2022)

• Record Type: Journal Article
• Authors: Hu, Liangwei; Fan, Baoyan; Fang, Ziyan; Zhang, Guanghui; Zhang, Qingfeng; Zhang, Guangzu; Zhang, Haibo; Jiang, Shenglin; Chen, Yong; Shen, Meng
• Is Part Of: Acta materialia. Volume 238(2022)
• Publication Date: 2022-10-01
• Subjects: composition and microstructure modulation -- Room-temperature pyroelectric coefficient -- Depolarization temperature -- Na0.5Bi0.5TiO3-xNa0.5Bi4.5Ti4O15; Materials -- Periodicals; Materials science -- Periodicals; Materials -- Mechanical properties -- Periodicals; Metallurgy -- Periodicals; Chemistry, Inorganic -- Periodicals; 620.112
• DOI: 10.1016/j.actamat.2022.118194
• Languages: English
• ISSNs: 1359-6454

Abstract

Abstract: Lead-free pyroelectric materials with high room-temperature pyroelectric coefficient ( p ) and depolarization temperature ( T d ) are in great demand for uncool infrared detectors. However, the state-of-the-art unleaded pyroelectric ceramics are confronted with challenge of increasing room-temperature pyroelectric coefficient at cost of declining depolarization temperature. Herein, we report that high room-temperature p of 5.28 × 10 −4 C m − 2 K −1 with T d of 175 °C can be simultaneously achieved by introducing Na0.5 Bi4.5 Ti4 O15 into Na0.5 Bi0.5 TiO3 solid solution system. Structure resolution revealed that the diffusing of Na0.5 Bi4.5 Ti4 O15 not only modifies the structures of TiO6 octahedra and wipes the P 4bm nanodomains from the long-range ordered R 3c phase, resulting in high remnant polarizations and enhanced room-temperature p, but also facilitates the electron transfer in the formation of Ti-O covalent bond and enhances the strength of Ti-O covalent bonds to improve the stability of crystal structure, leading to the enhancement of T d . Combined with enhanced room-temperature pyroelectric coefficient and high depolarization temperature, the Na0.5 Bi0.5 TiO3 - x Na0.5 Bi4.5 Ti4 O15 systems could be a promising lead-free pyroelectrics for uncool infrared detection. Graphical abstract: Image, graphical abstract