Double-perovskite tungsten molybdate red fluorescent powder for white light LED and preparation method of double-perovskite tungsten molybdate red fluorescent powder

Abstract

The invention relates to double-perovskite tungsten molybdate red fluorescent powder for a white light LED and a preparation method of the double-perovskite tungsten molybdate red fluorescent powder. The chemical expression of the red fluorescent powder is AA<II>1-xLi<+>B<II>O6:xEu<3+>, wherein Eu<3+> is an active ion doped to an A<II> site, and the doping amount x is more than or equal to 0.01 and less than or equal to 0.6; A is any one of or a combination of more of divalent alkaline earth metal ions Ca<2+>, Sr<2+> and Ba<2+>; A<II> is any one of or a combination of more of trivalent rare-earth ions La<3+>, Gd<3+>, Y<3+> and Sc<3+>; B<II> is any one of or a combination of W<6+> and Mo<6+>; and the red fluorescent powder is prepared by adopting a low-temperature combustion method. The double-perovskite tungsten molybdate red fluorescent powder disclosed by the invention can be efficiently excited by near ultraviolet and blue light chips, the luminous efficiency is improved, the preparation process is simple, and the synthesis temperature is low, so that the double-perovskite tungsten molybdate red fluorescent powder is ideal red fluorescent powder suitable for the white light LED.

Description

technical field [0001] The invention belongs to the technical field of rare earth luminescent materials, and in particular relates to a double perovskite tungstomolybdate red fluorescent powder for white LEDs and a preparation method thereof. Background technique [0002] White LED (Light Emitting Diode) has the characteristics of low energy consumption, small size, no pollution, high luminous efficiency, long life and fast reaction rate. Lighting source. [0003] Using phosphor conversion is the most common way to achieve white LEDs. Currently commercialized phosphor-converted white LEDs usually use InGaN blue chips with a wavelength of about 460nm to excite YAG:Ce 3+ The yellow light produced by the phosphor is mixed with the rest of the blue light to form white light. However, due to the lack of red light components, the white light produced by this combination has disadvantages such as poor color rendering and high color temperature. In addition, the use of ultraviole...

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Problems solved by technology

However, when the radius is relatively large Ca 2+ for B Ⅰ When ion, Eu 3+ ions readily access the highly symmetric B Ⅰ position, making it difficult to obtain pure red light emission; and when using Mg with a relatively small radius 2+ for B Ⅰ When ions are used, although pure red light can be obtained, there are still problems such as high reaction temperature, impure product, and low doping concentration, which lead to a series of defects such as complex process, increased process cost, and low luminous efficiency.

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