[17a-E502-1~13] 7.1 X-ray technologies

▲ [17a-E502-9] Studying the valence states of europium ions in BaAl₂O₄:Eu^2+,3+
via hard X-ray nanoprobe

〇BiHsuan Lin¹, Yu-Hao Wu¹, Shang-Wei Ke¹, Chien-Yu Lee¹, Bo-Yi Chen¹, Gung-Chian Yin¹, Mau-Tsu Tang¹ (1.NSRRC)

Keywords:X-ray nano probe, XEOL, XRF

In this report, the capabilities of Taiwan Photon Source (TPS) 23A X-ray nanoprobe will be introduced. We successfully demonstrate visualization methods for the characterization of BaAl₂O₄:Eu^2+,3+phosphors using hard X-ray nanoprobe [1]. Using X-ray fluorescence (XRF) mapping, we can not only obtain information on the elemental distributions, but also clearly perform the valence state distributions of the Eu²⁺and Eu³⁺ions. The accuracy of the estimated valence state distributions was examined by using X-ray absorption spectroscopy (XAS) across the Eu L₃-edge (6.977 keV). The X-ray excited optical luminescence (XEOL) spectra exhibit different emission behaviors in the selected local areas. XEOL mapping can obtain their corresponding emission distributions. The emission behaviors can be understood through the correlation analysis. The results demonstrated that the main contribution to the luminescence intensity of the BaAl₂O₄:Eu^2+,3+comes from the Eu²⁺activator and the emission intensity will not be influenced by the concentration of Eu²⁺or Eu³⁺ions. TPS 23A X-ray nanoprobe will open new avenues with great characterization ability for unraveling the emission mechanisms of phosphor materials.
[1]Yu-Hao Wu, Yung-Yang Lin, Jeng-Lung Chen, Shih-Yu Fu, Shu-Chi Huang, Chien-yu Lee, Bo-Yi Chen, Gung-Chian Yin, E-Wen Huang, Mau-Tsu Tang and Bi-Hsuan Lin. Journal of Synchrotron Radiation(2022) 29, 456.