Down-conversion luminescence of Ce-Yb ions in YF<inf>3</inf>

Abstract

© 2019 Elsevier B.V. The single-phase Y1-x-yCexYbyF3 solid solution powders were prepared by melt crystallization technique. The 5d-4f interconfigurational luminescence of Ce3+ ions and 2F5/2-2F7/2 luminescence of Yb3+ ions in YF3 crystalline powder doped with Ce3+/Yb3+ ions pair upon 266 nm excitation were studied. The energy transfer from Ce3+ to Yb3+ after 266 nm excitation has complex character and deals with the UV excitation induced dynamic processes and color centers formation in YF3:Ce3+ powders. It was shown that UV light irradiation leads to in absorbing in 525–650 nm spectral range which is not observed for Ce3+-Yb3+ containing samples. This speaks for additional channels of Ce3+ and Yb3+ excitation as a result of recombination of free charge carriers originated from excited state absorption by Ce3+ ions and trapped by Yb3+ ions. The efficiency of energy transfer from Ce3+ to Yb3+ was 22,6% for YF3:Ce(0.05 mol. %):Yb(10.0 mol.%) solid solution with 0,91% down-conversion luminescence external quantum yield.