| White LED,which is so called the next general lighting,is a topic of increasing interest due to their high luminous efficiency, low power consumption, environment friendly, reliability, long life, and so on. The pc-LED (phosphor-converted) method which connects InGaN LED with the phosphor is most common. So the phosphor for White LED is a novel topic of increasing interest. This paper intends to obtain phoshors for white LED by high-temperature solid-state reaction which could can be excited by blue or UV(n-UV) light and research optical properties of the phosphors.(1) The application and mechanism of the phosphor, the development of phosphor for white LED is introducted and evaluates a variety of White LED phosphors' performance and the problems.(2) By changing the chemical proportion of the samples, the temperature of the synthesis and other conditions, on the basis of lots of experiments, we find two groups of Eu2+ doped Sr10-x(PO4)6Cl2:Eu2+ formulas and best synthesis conditions. The intensity of the phosphor Sr9.88(PO4)6Cl2:0.12Eu2+ is 2.4 times of that of BAM under 400nm excited.(3) The Ce3+doped alkaline yttrium aluminum silicate and high temperature Yellow-green light emitting phosphor are analyzed. The effect of temperature and doping concentration of Ce3+ on the luminescence of Ca1.5Y1.5Al3.5Si1.5O12: xCe3+ and energy transfer from the Ce3+ (I) to Ce3+ (II) in the Ca1.5Y1.5Al3.5Si1.5O12 host were investigated.. Ca1.5Y1.5Al3.5Si1.5O12: xCe3+ is a high-quality green phosphor under the excitation of about 450 nm blue light , ranging from green 500 nm to 700 nm.(4) The phosphor CaO:xCe3+,Mn2+ have been obtained by solid-state reaction and their luminescent properties of the excitation at about 460 nm exhibit an intense yellow-orange emission from 500 to 750nm.By applying these phosphors and InGaN blue chip (460nm), the white LEDs can generate bright warm light, making these phosphors attractive as conversion phosphors for white LED application. |
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