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

Abstract The present paper discusses the optical and electrical properties of (Ba 0,6 Sr 0,3 Ca 0,1 )TiO 3 (BSCT) doped with Tb 3+ 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 4f 8 → 5d 1 4f 7 transition at 270 nm associated with 5d 1 low-spin states. In consequence, strong emission band at 545 nm corresponding to 5 D 4 → 7 F 5 transition characterized by the decay constant of 2 ms 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 300 K 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.