Photoluminescence properties of rare earths (Eu ³, Tb ³, Dy ³ and Tm ³) activated NaInW <inf>2</inf>O <inf>8</inf> wolframite host lattice

The photoluminescence (PL) studies on NaIn 1-xRE xW 2O 8, with RE=Eu 3, Tb 3, Dy 3 and Tm 3 phases have shown that the relative contribution of the host lattice and of the intra-ff emission of the activators to the PL varies with the nature of the rare earth cation. In the case of Dy 3 and Tm 3 activators, with yellow and blue emission, respectively, the energy transfer from host to the activator plays a major role. In contrast for Eu 3, with intense red emission, the host absorption is less pronounced and the intra-ff transitions of the Eu 3 ions play a major role, whereas for Tb 3 intra-ff transitions are only observed, giving rise to green emission. © 2011 Elsevier Inc. All rights reserved.