Preparation and luminescence properties of Eu2+-doped BaSi2O5 glass-ceramics

We report on the preparation of Eu2+-doped BaSi2O5 glass-ceramics by crystallizing an Eu3+-doped barium-silicate glass at temperatures in the range from 750 to 1100 degrees C. Single phase BaSi2O5 glass ceramics can be obtained by thermal annealing at temperatures of about 950 degrees C. The luminescence intensity of Eu2+ increases dramatically if monoclinic BaSi2O5 is formed. Monoclinic Eu2+:BaSi2O5 shows efficient, broad band luminescence between 450 and 550 nm by excitation in the near UV. Annealing at temperatures > 1000 degrees C leads to orthorhombic BaSi2O5 with much smaller Eu2+ luminescence. Static and time-resolved luminescence measurements indicate that Eu2+ ions are incorporated into the BaSi2O5 crystallites while Eu3+ ions remain in the amorphous phase. (C) 2011 Elsevier B.V. All rights reserved.