A kind of red fluorescent powder and molecular sieve composite luminescent material and its preparation method and application

Abstract

The invention discloses a preparation method of a compound luminescent material with red fluorescent powder and molecular sieves. The method comprises the following steps: (1) exchanging molecular sieves through ions by adding the molecular sieves into a halogenated cesium solution, stirring, centrifuging, washing, drying and repeating the above steps to obtain Cs<+> exchanged molecular sieves; (2) preparing a precursor solution with Si<4+> and Mn<4+> by taking H2SiF6 as a reaction solution system, adding K2MnF6 powder and dissolving to prepare the precursor solution with Si<4+> and Mn<4+>; and (3) adding the Cs-Y molecular sieves prepared in the step (1) into the precursor solution with Si<4+> and Mn<4+> obtained in the step (2), stirring and fully reacting, then collecting precipitate, centrifuging, washing and drying. The compound material is capable of effectively increasing the display index in lighting indexes and reducing the color temperature, has excellent heat stability and moisture resistance, and can be applied to the field of white LED.

Description

technical field [0001] The invention relates to red fluorescent powder, in particular to a composite luminescent material of red fluorescent powder and molecular sieve and its preparation method and application. Background technique [0002] At present, the mainstream of white LED business is GaN blue chip+YAG:Ce 3+ The yellow phosphor is synthesized and prepared, which leads to the characteristics of the prepared product with low color rendering index (Ra<80) and high color temperature (Tc>4500k), which is due to the lack of red light components resulting in cold light lighting and thus Not suitable for indoor lighting applications. At present, the nitride-doped Eu 3+ As a commercial red powder, although the thermal stability is relatively good, there are still defects. In addition to the harsh preparation process and high raw material costs, it also shows broadband absorption and long emission bands. Broadband absorption is used in GaN+YAG:Ce 3+ Self-absorption oc...

AI Technical Summary

Problems solved by technology

The thermal stability is relatively good. At present, the quantum efficiency begins to decline after reaching 150°C, and moisture resistance is a difficulty, which directly leads to the disadvantage of short service life after the synthesis of devices. Although some researchers currently use organic surface ligands to K 2 SiF 6 :Mn 4+ Wait for A 2 BF 6 (A: K, Na, Cs; B: Si, Ti, Ge) are coated or modified to make the surface of the red powder into a hydrophobic material, but there are defects due to interface effects. In the complex real environment of natural high temperature and high humidity However, the luminous efficiency is often seriously attenuated and the stability is poor in the solid state, which limits its further application in the field of white light LEDs and other luminescent materials to a certain extent.

Images