Transparent Eu3+doped oxyapatite glass ceramics: Crystallization kinetics, structural and optical properties

Transparent Eu3+-doped oxyapatite glass ceramics (GC) have been prepared. A mean crystallization activation energy of 389.58 kJ/mol is determined in crystallization kinetics study. The Avrami's parameter is evaluated to be 2.65, indicating that bulk crystallization is the dominant mechanism. Effect of Eu2O3 dopant on the crys-tallization behavior was discussed. The precipitation of oxyapatite nanocrystals exhibiting a slight lattice contraction in glass is confirmed by X-ray diffraction (XRD) and transmission electron microscopy (TEM) mea-surements, resulting from the partition of some europium ions into crystals. Photoluminescence analysis reveals that crystallization could promote the oxidation of Eu2+ to Eu3+ possibly due to europium ions partition on La3+ lattice sites. Temperature-dependent photoluminescence spectra indicate that such oxyapatite GC phosphor exhibits excellent thermal stability with an activation energy of 0.326 eV. This study reports the possibility of developing oxyapatite GC phosphor for light conversion application.