| White-light light emitting diodes (LED) possess such excellent performance as low power consumption, long lifetime, environmental protection and fast response time, and so on. The YAG:Ce phosphor is currently commercially used as yellow phosphors for white LEDs, but unfortunately, it has a low color rendering index(CRI) for home lighting. Therefore, it is necessary to develop and study light conversion phosphors showing multi-color emitting have an extreme important theoretical and application value for solid state lighting. In this dissertation, tow series of light conversion phosphors for white LEDs have been synthesized and characterized by micro emulsion and microwave radiation method. The luminescent properties of Li2CaSiO4:Eu2+ were studied. The blue-green emission of Li2CaSiO4:Eu2+ was produced when it was excited by ultraviolet and blue light, the main emission peak was at 478nm.In addition, a series of molybdate doped with Eu3+ phosphors has been synthesised by microemulsion method. Eu3+ doped CaMoO4 micro/nano phosphors with Dumbbell-shaped have been synthesized by the microemulsion method. The phosphors may be a red phosphor candidate for applications in white LEDs. An efficient red phosphor, BaMoO4:Pr3+, had been fabricated by microemulsion method. A strong red emission centered at 643 nm corresponding to the 3P0-3F2 transition of Pr3+ was observed under 430-500 nm excitation.
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