| White light-emitting diodes (LED) have been called as the fourth generation solid-state lighting source due to their small volume, energy-saving, environment-friendly, and long lifetime. Recently, phosphor-converted (pc) method is the most common to fabricate white LED, which has attracted considerable intentions of researchers and countries. As the important ingredient in pc-white LED, phosphor affects the development and application of white LED directly. With the development of phosphor for white LED in modern industry, there are several urgent problems needed to be solved. First of all, the absence of red phosphor which can be effectively excited by blue and ultraviolet or near ultraviolet light leads to low color render indexing and the unstable of luminescence. Secondly, it is an urgent need to develop single-phased white-emitting phosphors, which would provide a new and feasible method for the fabrication of white LED. In addition, the commercial phosphors are generally prepared by conventional high temperature solid state reaction which gradually cannot meet the demand of development in the area of light and display because of energy-consuming and uncontrollable for the shape of particles. Therefore, it is great meaningful to develop new good properties of different color-emitting phosphors and propose a novel energy-saving way for the parparation of phophors.In this article, on the one hand, red phosphors, which can be pumped by blue and ultraviolet or near ultraviolet effectively, have been prepared by molten salt synthesis method in low temperature. On the other hand, a single-phazed white-emitting phosphor for white LED has been synthesized by high temperature solid state reaction. Furthermore, the corresponding luminescence properties are also investigated. The main contents in our work are listed in the followings:(1) Good property of Y2O3:Eu red phosphor has been successfully fabricated by molten salt synthesis method and can be excited by blue as well as ultraviolet light effectively. The effect of annealed temperature, annealed time, molten salt content, Eu3+ doping concentration on the luminescence properties of Y2O3:Eu are discussed and the optimal synthesis conditions are also figured out.(2) Y2O3:Eu red phosphor has been successfully prepared via co-precipitation-molten salt synthesis method and can be pumped by blue as well as ultraviolet light effectively. The dependence of luminescence properties on calcined temperature and fluxes are studied. The luminescence mechanisms are also discussed.(3) Y2O3:Eu red phosphor for white LED has been successfully prepared by surfactant assisted co-precipitation-molten salt synthesis method in low temperature. Annealed temperature and surfactant concentration are explored in the effect of luminescence properties of products and the corresponding mechanisms are investigated.(4) A new and high performance of Y2O3:Eu, Bi red phosphor, which can be monitered by blue and ultraviolet light effectively, has been fabricated via molten salt synthesis method. The luminescence properties of as-synthesized samples are discussed with respect to different Bi3+ doping concentrations. More importantly, the mechanisms about luminescence and energy transferring in Y2O3:Eu, Bi are studied.(5) A novel single-phased Ca9Y(PO4)7:Tm3+, Dy3+ white-emitting phosphor has been successfully synthesized by high temperature solid state reaction. The luminescence mechanisms of as-prepared specimens are discussed. In addition to this, the effect of Tm3+ and Dy3+ doping concentrations on the luminescence properties and color coordinate of as-fabricated products are also investigated.
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