| This paper prepared the Ca1-xEuxAl Si N3(x=0.02, 0.04, 0.06, 0.08, 0.1)series and the Ca1- xCexAlSiN3(x=0.04, 0.06, 0.08, 0.1)series of white LED with nitride red phosphors by combining with rapid melting alloy precursors、high temperature and normal pressure nitriding sintering method. Among them, the Ca1-xEuxAl Si N3 series of phosphors were respectively adopted Ca1-xEuxAl Si quaternary alloy and Ca1-xAlSi ternary alloy preparation of precursors and then nitriding sintering under high temperature and normal pressure. Studied and analyzed the structure of the phosphor and the luminescence performance,etc. by using X-ray diffraction(XRD), scanning electron microscopy(SEM), energy dispersive X-ray(EDX), X-ray photoelec tron spectrometer(XPS) and fluorescence spectrum measurement. Results show that the Ca1-xEuxAlSiN3(x=0.02, 0.04, 0.06, 0.08, 0.1)series of phosph ors made by quaternary alloy has good by quaternary alloy made from CaAl-Si N3 phase structure. With the increase of the concentration of Eu, the europium in the alloy precursors easily oxidized to form europium oxide, while in the phosphors exist in the form of lightless Eu3+, phase structure, EDX, XPS analysis show that Eu3+ exists in the form of europium oxide. With the increase of concentration of Eu, the light emitting peak position first red shift then blue shift and at the same time, the fluorescence relative strength increases first and then decreases. A preliminary analysis of these is because of the doped Eu2+ ion concentration quenching effect and degree of different oxidation in the process of alloying forming Eu3+. In order to avoid the oxidation of Eu in the process of alloy, this paper prepared the Ca1-xEuxAl Si N3(x=0.02, 0.04, 0.06, 0.08, 0.1)series phosphors by combining with Ca1-xAlSi ternary alloy precursors and Boride europium high temperature and normal pressure reaction. Results show that the boride europium prepared by europium oxide and sodium borohydride europium was reduced to Eu B6 well, thus the Ca1-xEuxAl SiN3 materials were formed in the course of nitride reaction, Eu3+ content had significantly lower compared with quaternary alloy Eu3+, and when the Eu doping concentration in 0.02 the light relative intensity is also improved. On the basis of experiments before, this paper carried out exploratory experiments in the luminance of another kind of rare earth ion Ce3+ in the CaAlSiN3 system. The Ca1-xCexAlSiN3(x=0.02, 0.04, 0.06, 0.08, 0.1)series samples obtained by combining with quaternary alloy method and constant pressure annealing method, through the analysis of the structure and optical properties, this series of samples can form stable CaAlSiN3 main phase, little impurity phase, and can be effectively inspired by the 370-480 nm to get the orange light with 595-615 nm of emission main peak, over the simple studied, this lighting cover the transition emission of 5d to 2F7/2 and F5/2, The phosphors with ultraviolet light and blue light chips have orange light can be used in the power of warm white LED encapsulation type to use.The rapid melting alloy preparation method combined with high temperature and normal pressure annealing method compared with the currently used red phosphor powder preparation method has many advantages, for example the former is easy to operate, simple, safe and low cost and even can be made through the multielement alloy preparation. The nitride red phosphors get from the experiments has a stable phase structure and there is a room to further improve performance in it’s luminance. |
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