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This article first solid-state light-emitting materials, especially rare earth photoluminescence materials, the status quo, light-emitting characteristics, luminescence mechanism and preparation methods. Long Afterglow rare earth doped aluminates phosphors as a non-radioactive, environment-friendly, light-emitting performance features, is a very promising new material. But reported doped alkaline earth aluminates Long Afterglow synthetic high temperature synthesis process complexity and high cost of production shortcomings, severe constraints on its application. Simplify the production process of this kind of material, reduce production costs, the paper further explore the fluorescent material to the class of light-emitting mechanism and new preparation process, and obtained the following results: 1, the use of activated carbon reduction process, the choice of oxidation at 1350 ℃ under the conditions of aluminum and calcium carbonate as raw material, the mass fraction of 1.6% boric acid as a flux to add the amount of granular activated carbon for 1:10 as the reducing agent, natural cooling samples with the furnace thermostat 4h after the success of the system was the blue-violet light CaAl 2 O 4 : Eu 2 , Nd 3 long afterglow phosphors. Test the emission spectrum of the phosphor, the excitation and emission spectra are broadband spectrum, derived from the of Eu 2 characteristics of light-emitting, when the excitation wavelength λ ex 330nm when, the maximum luminous intensity of the phosphor, the main light emitting region is located in the the 430nm vicinity. 2, using a new synthetic method - burning the synthesis method successfully obtained CaAl 2 O 4 : the of Eu 2 , Nd < / sup> phosphors, detailed study of the furnace temperature, activator auxiliary activator, cosolvent and combustible luminescent properties of the phosphor, the preparation with excellent light-emitting properties of CaAl 2 O 4 : Eu 2 , Nd 3 Long Afterglow ideal process parameters. Experiments show that the chosen solution of Ca (NO 3 ) 2 and Al (NO , 3 ) 3 as raw material to The mole fraction of 0.12 H 3 BO 3 flux, 2.2 times the theoretical amount of urea as a reducing agent, and joined the mole fraction of 0.018 Eu 2 and 0.01 Nd of 3 in the synthesis temperature of 600 ° C in a muffle furnace to obtain excellent luminescence properties of CaAl 2 O 4 : Eu 2 , Nd 3 phosphors. Through the test of the excitation and emission spectra of the product, it is found that when λ ex for 290nm, generated by the light emitting performance is preferably corresponding to the emission light λ of EM 450nm. Further explore ways to improve the brightness of the light-emitting phosphors, respectively, Zr, Ce, and Sr partial substitution of Ca and product testing and analysis of the excitation and emission spectra. The results show that, when mixed with a small amount of Sr 2 ion the phosphor emission peak position unchanged, still at 450nm; When the amount continues to increase Sr 2 , phosphor the occurrence of peak red shift. As the Zr content increases, the emission peak is not moved, but the intensity of the emission peak changed. When incorporation of Ce 3 amount when its emission peak position unchanged, but the intensity of the light emitted Eu 2 ion enhanced.
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