Host absorption sensitizing and energy transfer to Eu3+ by Gd3+ in Ba6Gd2−xNa2Eux(PO4)6F2

Eu3+ activated fluoro-apatite phosphors Ba6Gd2−xNa2Eux(PO4)6F2 were synthesized using the traditional high temperature solid state reaction method, and their VUV–vis spectroscopic properties of Eu3+ were studied. The results show that phosphor Ba6Gd1.90Na2Eu0.10(PO4)6F2 has intense absorption in the VUV range because of Gd3+ ions as sensitizers. The energy transfer process from Gd3+ to Eu3+ in Ba6Gd2-xNa2Eux(PO4)6F2 were investigated and discussed in terms of luminescence spectra and decay curves, showing that the energy transfer of Gd3+→Eu3+ is efficient.

The Gd3+ ions can enhance the host-related absorption in VUV range. The energy transfer from Gd3+ to Eu3+ ions is efficient.Figure optionsDownload as PowerPoint slideHighlights
► The Gd3+ ions play an important role in enhancing the host-related absorption in VUV range.
► The charge-transfer energy of Eu3+ decreases from Ca2+ to Sr2+ and Ba2+ in M6Gd1.90Na2Eu0.10(PO4)6F2 (M=Ca, Sr, Ba).
► There is efficient energy transfer from Gd3+ to Eu3+ in Ba6Gd2−xNa2Eux(PO4)6F2.