Red fluorescent powder and preparation method thereof

Abstract

The invention relates to red fluorescent powder with water-proof performance. A general formula of the red fluorescent powder is Me2xBa1-xTi1-yF6:yMn4+; Me is Li, Na, K, Rb and Cs ions; x is greater than 0 and less than 1; and y is greater than 0 and less than 0.5. The red fluorescent powder is particularly prepared by the following steps: sequentially and slowly dropwise adding a Ba salt solutionand a Me salt into an H2TiF6 aqueous solution for reaction at normal temperature and pressure to prepare MexBa1-xTiF6, uniformly mixing and adding MexBa1-xTiF6 and KMnO4 into an HF aqueous solution for reaction to form a target product, namely Me2xBa1-xTi1-yF6:yMn4+. The fluorescent powder prepared by the method has the prominent advantages of narrowband emission, high lighting effect, high development and the like, is uniform in particle size, and has very good water resistance; the luminous intensity of the fluorescent powder in water can be greater than the original luminous intensity by above 70% and is good in stability; the fluorescent powder solves the problem of high possibility of wetting and hydrolysis of the traditional red fluorescent powder; the problems of performance degradation of the fluorescent powder due to a coating or an organic envelope are avoided; and the fluorescent powder can be widely applied to the technical field of high development and warm color temperature white light LED (light-emitting diode) package, fluorescent tube coating and the like and to illumination in some humid environments.

Description

technical field [0001] The invention relates to the technical field of luminescent materials, in particular to a red fluorescent powder and a preparation method thereof. Background technique [0002] The light emitting diode (LED) device has become the most important lighting tool of the new generation because it has [0003] It has the advantages of low power consumption, small size, high efficiency, long life and non-toxic substances. In LED packaging components, phosphor plays an important role, which determines the performance of WLED packaging, such as luminous efficiency, color rendering rate, correlated color temperature, color gamut, lifespan, etc. Currently commercial LEDs use InGaN blue chips and YAG:Ce 3+ made of yellow phosphor, however, YAG:Ce 3+ The emission spectrum of yellow phosphor lacks the red light part, so it is difficult to prepare white LED lamp beads with high color rendering and warm color temperature, which cannot meet the quality requirements o...

AI Technical Summary

Problems solved by technology

Although some researchers have proposed to protect the phosphor surface by coating or use an organic or inorganic coating on the surface to prevent the phosphor from contacting with water, the coating or organic-coated phosphor has poor weather resistance and its performance decays quickly in high temperature or ultraviolet environments. , some studies have also shown that through H 2 o 2 or H 2 C 2 o 4 etc. passivation treatment to build an inactivation layer as an isolation film, but this still cannot solve the fundamental problem. In some humid environments, lighting still requires the waterproof function of the phosphor itself.

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