Luminescent properties and energy transfer mechanism from Tb3+ to Eu3+ doped in Y3Al5O12 phosphors

摘要

The structural and luminescent properties of Y3Al5O12:Eu,Tb (YAG) compounds produced by a modified sol-gel method using glucose as a polymerising agent are investigated in this study. X-ray diffraction is utilised in order to analyse the formation of the crystalline phase. The luminescent properties are investigated by excitation and emission measurements from photoluminescence and X-ray excited optical luminescence (XEOL) measurements, which are strongly influenced by the concentration of Eu(3+)and Tb3+ dopants. X-ray absorption spectroscopy (XAS) is measured at the Eu L-III-edge in order to confirm the Eu valence. The results indicate good stability of Eu ions in the YAG structure when submitted to higher ionising energies. The chromaticity diagram indicates that, with different molar ratios of Eu(3+)and Tb3+ ions, it is possible to obtain white-light emission. In addition, it is observed that the amount of dopant/co-dopant ions leads to changes in the phosphorescent decay time. (C) 2020 Elsevier B.V. All rights reserved.