Tunable optical properties and DFT calculations of RE3þcodoped LaBO3 phosphors


Abaci Ö. C. , Mete E., Esentürk O., Yilmaz A.

Optical Materials, vol.98, no.109487, pp.1-10, 2019 (Peer-Reviewed Journal)

  • Publication Type: Article / Article
  • Volume: 98 Issue: 109487
  • Publication Date: 2019
  • Journal Name: Optical Materials
  • Journal Indexes: Science Citation Index Expanded, Scopus
  • Page Numbers: pp.1-10

Abstract

In this study, single phase DyxLa1-xBO3, DyxCeyLa1-x-yBO3, DyxEuyLa1-x-yBO3, and TbxCeyLa1-x-yBO3 phosphors were successfully synthesized through the microwave assisted solid state method with urea. Synthesized com-pounds were characterized by X-Ray Diffraction, Fourier Transform Infrared spectroscopy, Scanning Electron Microscope, and Fluorescence spectroscopy. Thermal stabilities of the phosphors were studied with temperature dependent fluorescence measurements. In addition, density functional theory calculations were performed to investigate preferential Dy3þion doping sites in LaBO3 lattice. The findings of the study revealed over ten times increase in the emission intensities of phosphors were observed with Ce3þcodoping. The highest luminescence intensities were recorded for Dy0.09Ce0.05La0.86BO3 and Tb0.07Ce0.05La0.88BO3 phosphors. Furthermore, energy transfers were supported by luminescence lifetime measurements. Temperature dependent fluorescence mea-surements showed their thermal stabilities. According to the CIE 1931 color space, the colors of the Dy3þonly doped, Ce3þ/Dy3þ; Ce3þ/Tb3þand Dy3þ/Eu3þcodoped phosphors were determined as off-white, white, green and yellow-orange, respectively. Intensities of the bands and the colors of the phosphors can be tuned with the choice of codopant ions or with adjustments in their concentration ratio.