Synthesis and spectral characterization of Sr4Al14O25:Eu2+/Dy3+ blue-green phosphorous powders by sol-gel method

Demirci S., Gültekin S., Akalın S. A., Öter Ö., Ertekin K., Çelik E.

MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING, cilt.31, ss.611-617, 2015 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 31
  • Basım Tarihi: 2015
  • Doi Numarası: 10.1016/j.mssp.2014.12.066
  • Dergi Adı: MATERIALS SCIENCE IN SEMICONDUCTOR PROCESSING
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.611-617
  • Anahtar Kelimeler: Luminescence powders, Blue-green phosphor, Long persistent Sr4Al14O25:Eu2+/Dy3+ phosphorous, Sol-gel, argon atmosphere, LONG PHOSPHORESCENCE, NANOMETER POWDERS, LUMINESCENCE, MECHANISM, DY3+, CO, SR4AL14O25-EU2+, SR, BA, EU
  • Marmara Üniversitesi Adresli: Hayır

Özet

Highly intense, long persistent Sr4Al14O25:Eu2+/Dy3+ phosphorous powders were prepared for the first time by sol-gel method under argon atmosphere. 2.5 mol% of H3BO3 was added as fluxing agent. Characterization of the powders was carried out by X-ray diffractometer (XRD), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The average particle size of the fabricated phosphor powders was found to be 460 nm in dispersed form in pure water. UV-Vis, steady-state and time resolved fluorescence spectroscopy techniques were used for spectral characterization of the powders. The phosphors exhibited two different emission bands at 449 and 550 nm upon excitation at 400 nm. It is observed that the position and the intensity of the emission band strongly depends on the excitation wavelength and shifts toward lower energy and intensity with increasing wavelength of the excition source. The broad band luminescence characteristics of the Sr4Al14O25:EU2+/Dy3+ were observed at 492 nm in the absence of the excitation source. The Sr4Al14O25:Eu2+/Dy3+ phosphor can be efficiently excited with the visible fraction of the light and show persistent luminescence, long and strong afterglow up to 35 min after removal of the excitation source. (C) 2015 Elsevier Ltd. All rights reserved.