Green emission from barium–strontium titanate matrix introduced into nano-porous anodic alumina

• Published in: Optical materials Vol. 34; no. 9; pp. 1570 - 1574
• Main Authors: Podhorodecki, A., Gaponenko, N.V., Banski, M., Rudenko, M.V., Khoroshko, L.S., Sieradzki, A., Misiewicz, J.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.07.2012
• Subjects: Barium–strontium titanate; Luminescence; Perovskite; Superparaelectric; Terbium; Barium–strontium titanate; Perovskite; Terbium; Superparaelectric; Luminescence
• ISSN: 0925-3467; 1873-1252
• DOI: 10.1016/j.optmat.2012.03.025

[Display omitted] ► We successfully introduced Tb+3 ions into (Ba0,6Sr0,3Ca0,1)TiO3 and observed its strong green emission. ► Excitation mechanism of Tb+3 has been explained. ► Superparaelectric behavior of (Ba0,6Sr0,3Ca0,1)TiO3:Tb matrix has been observed. The present paper discusses the optical and electrical properties of (Ba0,6Sr0,3Ca0,1)TiO3 (BSCT) doped with Tb3+ ions and deposited onto nano-porous anodic alumina using sol–gel method. Photoluminescence (PL), PL time-decay and total photoluminescence excitation spectroscopy data obtained from the structure xerogel/porous anodic alumina are compared with the data obtained for Tb in porous anodic alumina deposited by immersion. It has been shown that the most efficient excitation channel of Tb ions in BSCT xerogel is 4f8→5d14f7 transition at 270nm associated with 5d1 low-spin states. In consequence, strong emission band at 545nm corresponding to 5D4→7F5 transition characterized by the decay constant of 2ms has been observed for the samples annealed at above 750°C. This emission significantly and continuously decreases when the temperature is increased from 10 up to 300K without any abrupt change. This result correlates with the lack of ferroelectric phase transition and appearance of superparaelectric behavior of BSCT matrix observed with electrical measurements.