Silicon nitride nanorod fluorescent powder and preparation method and application thereof

Abstract

The invention discloses silicon nitride nanorod fluorescent powder and a preparation method and application thereof. The preparation method comprises the steps that crystalline silicon waste is ground into silicon powder, Si powder and a europium source are weighed according to the proportion and fully mixed and ground, the ground mixture powder is put into a crucible and put into a high-temperature tube furnace, inert gas is introduced into the high-temperature tube furnace, and heated to a specified temperature at a certain heating rate, heat preservation is performed for a period of time, cooled to room temperature after heat preservation is finished, and ground to obtain the nitride yellow fluorescent powder. The substrate of the related fluorescent powder material is silicon nitride, the synthesis process is simple, waste is turned into wealth, an additional vacuum system is not needed, Eu < 2 + > / Eu < 3 + > coexistence can be realized, and the luminescence spectrum can be expanded and subjected to red shift. In addition, the obtained fluorescent powder is good in chemical stability, low in thermal quenching and high in luminous intensity, and can meet the requirements of fluorescent powder for high-power LEDs and the requirements of industrial production. (The attached drawing of the abstract is a composite spectrum and CIE drawing of the product and a blue light chip).

Description

technical field [0001] The invention belongs to the technical field of nanomaterials and luminescent powder preparation, and in particular relates to a silicon nitride nanorod fluorescent powder and a preparation method and application thereof. Background technique [0002] Due to its low energy consumption and high efficiency, white light-emitting diodes (LEDs) have developed rapidly and are gradually replacing traditional incandescent and fluorescent lamps, becoming a priority industry for national lighting projects. At present, there are three main methods to realize white LED: [0003] 1. Simultaneously excite red, green and blue phosphors with ultraviolet chips; [0004] 2. Direct combination of red, green and blue light-emitting chips; [0005] 3. Use the blue light chip to excite the yellow phosphor. [0006] The current mainstream commercial white LED is mainly the third implementation. Therefore, it is of great significance for the synthesis of yellow-emitting p...

AI Technical Summary

Problems solved by technology

However, most of these compounds have complex structures, almost all of which are ternary, quaternary or even quinary compounds. The requirements for the types of raw materials are also various, which is not conducive to large-scale synthesis.

For example, the existing α-SiAlON for white LED: Eu 2+ Yellow phosphor, which introduces many types of atoms, and the synthesis temperature is too high, must reach above 2000 ° C; there is also a La 4-x Ca(SiO 4 ) 3 O:xCe 3+ , x=0.001~0.10 Yellow phosphor, although the synthesis method is straightforward and simple, but there are many types of raw materials, and toxic, flammable and explosive CO, etc. are used, which brings many specific problems to the actual production process

Although there have been some literature reports on rare earth doped silicon nitride phosphors, the luminous performance is "blue", not yellow in the true sense.

The main reason is that the doped Eu is mainly divalent and lacks trivalent state, resulting in a relatively narrow luminous band and a blue-dominated luminous position.

Therefore, how to use a process to realize the co-existence of divalent and trivalent Eu in phosphors is still a blank and challenge in technology.

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