Red fluorescent powder capable of being simultaneously effectively excited by near ultraviolet and blue LED light

Abstract

The invention discloses red fluorescent powder capable of being simultaneously effectively excited by near ultraviolet and blue LED light. In the red fluorescent powder, ZnMoO4 is taken as a substrate, Eu3+ is taken as an activation center, and one or more of Li+, Na+, K+, Rb+ and Ag+ are taken as charge compensators, and one or more of Bi3+, Sm3+, Gd3+, Sc3+, Y3+, La3+, Gd3+ and Yb3+ with proper concentration are introduced to partially replace Zn so as to improve the absorption of the Eu3+ under the excitation at 395 nm and 466nm. The chemical composition general formula of the red fluorescent powder is Zn1-2x-y-zAxByMoO4:EuxBizSmw, wherein A is one or more of Li, Na, K, Rb and Ag; B is one or more of Sc, Y, La, Gd and Yb; and x is more than or equal to 0.05 and less than or equal to 0.4, y is more than or equal to 0 and less than or equal to 0.1, z is more than or equal to 0 and less than or equal to 0.1, and w is more than or equal to 0 and less than or equal to 0.05. The invention is applied to the preparation of the red fluorescent powder capable of being simultaneously effectively excited by the near ultraviolet and blue LED light.

Description

technical field [0001] The invention relates to a red fluorescent powder which can be effectively excited by near-ultraviolet and blue LED light at the same time and a preparation method thereof, belonging to the technical field of rare earth luminescent materials. Background technique [0002] Red phosphor is an important raw material for improving the color rendering index of white LEDs, Y 2 o 2 S:Eu 3+ It is a very widely used red powder for displays at present, but the commercial red phosphor Y 2 o 2 S:Eu 3+ There are many disadvantages: low luminous efficiency under near ultraviolet excitation, only green powder (ZnS:Cu + , Al 3+ ) and blue powder (BaMgAl 10 o 17 :Eu 2+ ) of one eighth. Unstable chemical performance, short life, easy to decompose and produce SO which is harmful to human body 2 The precipitation of gas and sulfur elements will also cause corrosive effects on the chip, resulting in the failure of the entire device. This is the main reason why ...

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Problems solved by technology

[0002] Red phosphor is an important raw material for improving the color rendering index of white LEDs, Y 2 o 2 S:Eu 3+ It is a very widely used red powder for displays at present, but the commercial red phosphor Y 2 o 2 S:Eu 3+ There are many disadvantages: low luminous efficiency under near ultraviolet excitation, only green powder (ZnS:Cu + , Al 3+ ) and blue powder (BaMgAl 10 o 17 :Eu 2+ ) one-eighth of

However, these molybdate series phosphors still have a common shortcoming: the half-maximum width of the excitation spectrum at around 395nm in the near ultraviolet is narrow.

Due to the narrow half-maximum width of the excitation spectrum, it will not be possible to accurately achieve the best effect when matching the phosphor powder with the LED chip, resulting in a series of problems such as low luminous brightness during use.

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