抄録
White light emitting diodes (LEDs) are expected to be used as lighting of the next generation for, for example, headlights, back lighting of liquid crystal displays (LCDs), illuminations, and so on. However, red emitting phosphors used for white LEDs have lower luminance efficiency than other emitting color phosphors because of larger stokes shift. La2O2S:Eu is known as red emitting phosphor; it shows good luminescence under near-ultraviolet excitation. In this study, synthesis of La2O2S:Eu using the citric acid gel method has been investigated. The results show that the particle size can be controlled by changing pre-firing conditions.
