Effects of the surface coating of BaMgAl10O17:Eu2+ phosphor with SiO2 nano-particles

BaMgAl10O17:Eu2+(BAM) phosphors were coated with SiO2 nano-particles by a modified sol-gel method. In order to elucidate the effects of SiO2 coating onto BAM phosphor, the luminescent decay time is measured before and after SiO2 coating. It was revealed that surface coating of BAM phosphors with SiO2 leads to an increase in luminescent decay time and quantum efficiency, due to the suppression of nonradiative decay via surface defects. The experimental results suggest that the nonradiative decay via surface defects is an important relaxation process, related to the optical properties of display devices such as plasma display panels (PDP) and lamps.