Photoluminescence properties of submicrometer phosphors with different crystallite/particle sizes

The effects of crystallite and particle sizes on the photoluminescence (PL) characteristics of submicron-sized Y(2)O(3):Eu(3+) phosphors were investigated. The crystallite and particle sizes were controlled independently. The results revealed that the crystallite and particle sizes played different roles in the control of PL characteristics of the phosphors. The blue shift of the charge transfer band in excitation spectra was mainly due to the particle size effect, because the crystallite boundary of the particles had no effect oil the charge transfer. In contrast. the decrease in crystal symmetry ratio, which is the ratio of C(2) to C(3i) sublattice populations in PL emission spectra, was mainly due to the crystallite size effect, since the amorphous/defect parts were located on the surface of the crystallites/particles.