Luminescent–electrical–magnetic performances of sol–gel-derived Ni2+-modified Bi0.5Na0.5TiO3

• Published in: Journal of materials science. Materials in electronics 2017-08, Vol.28 (16), p.12021-12025
• Main Authors: Wu, Xiao, Liu, Chunwen, Tse, Mei Yan, Lin, Cong, Zheng, Xinghua, Lin, Mei
• Format: Article
• Language: English
• Subjects: Bismuth titanate; Broadband; Ceramics; Characterization and Evaluation of Materials; Chemistry and Materials Science; Communication; Dielectric loss; Dielectric properties; Ferroelectric materials; Ferroelectricity; Ferroelectrics; Ferromagnetism; Grain boundaries; Grain growth; Grain size; Materials Science; Microstructure; Optical and Electronic Materials; Optical communication; Perovskite structure; Perovskites; Polyvinyl alcohol; Sintering; Sol-gel processes
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-017-7012-5

2.5 mol% Ni 2+ -modified Bi 0.5 Na 0.5 TiO 3 (BNT–Ni-0.025) ceramic has been fabricated based on the sol–gel method. The BNT–Ni-0.025 ceramic possesses a rhombohedral perovskite structure with denser microstructure than that of pure BNT ceramic. The introduction of certain amount of Ni 2+ (e.g. 2.5 mol%) in BNT can reduce the sintering temperature (50 °C lower), effectively suppress the grain growth, greatly decrease the dielectric loss and then produce multifunctionality. The BNT–Ni-0.025 ceramic also exhibits good ferroelectric properties with a large remanent polarization of ~26 μC/cm 2 . The observed weak ferromagnetism of the ceramic can be ascribed to the exchange interaction between free carriers (oxygen vacancy induced delocalized electrons) and the localized Ni 2+ ions. Under the excitation of 370 nm, the BNT–Ni-0.025 ceramic shows broadband NIR luminescence centered at ~1480 nm from Ni 2+ with long emission lifetime (28 µs), which can cover the optical communication window and be applied in broadband optical amplifiers. The multifunctional BNT–Ni-0.025 ceramic shows potentials in the application of optical–electrical–magnetic areas.