Effect of SiO2 coating on photoluminescence and thermal stability of BaMgAl10O17: Eu2+ under VUV and UV excitation

The BaMgAl10O17: Eu2+ (BAM) phosphors used as blue component of tricolor fluorescent lamps (FLs) and plasma display panels (PDPs) have the problems of thermal degradation in the process of fabrication. In this work, the nanometer SiO2 was homogenously coated on it. The luminescence and thermal stability are investigated for the excitation in both the UV and the VUV regions. The results demonstrate that after coating, there is an increase in the luminescence intensity in the UV region, while no obvious increase is observed in the VUV region. In addition, the thermal stability was largely improved under both UV and VUV excitations. The underlying mechanism is elucidated.