Method for preparing luminescent powder of light emitting diode in white light with high brightness and adjustable wavelength

A technology of light-emitting diodes and phosphors, which is applied in the direction of luminescent materials, chemical instruments and methods, and sustainable buildings. It can solve the problems that the luminous brightness cannot meet the needs, and the luminous intensity of phosphors needs to be improved, so as to improve the color temperature and color coordinates. The effect of improving dispersion

Inactive Publication Date: 2004-03-10
OCEAN UNIV OF CHINA
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

At present, the luminous intensity of phosphor powder used in packaging white LED needs to be improved. The luminous intensity of white LED is less than 6cd. If it is used for lighting, its luminous brightness cannot meet the needs.

Method used

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  • Method for preparing luminescent powder of light emitting diode in white light with high brightness and adjustable wavelength
  • Method for preparing luminescent powder of light emitting diode in white light with high brightness and adjustable wavelength
  • Method for preparing luminescent powder of light emitting diode in white light with high brightness and adjustable wavelength

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0011] weigh Y 2 o 3 : 4.0g, Al 2 o 3 : 3.1g, activator CeO 2 : 0.3g, flux NaF: 0.5g and H 3 BO 3 : 0.1g, mixed and ground for 20-40min, put into a crucible, baked at 1200°C-1550°C for 5 hours in a reducing atmosphere provided by a carbon rod, stopped heating and then cooled to obtain the phosphor powder of the present invention.

Embodiment 2

[0013] The mixture described in the present invention also can be mixed with rare earth element R, promptly adopts main chemical composition to be (Y 1-x-y Ce x R y ) 3 Al 5 o 12 , wherein R is erbium (Er), praseodymium (Pu), gadolinium (Gd), terbium (Tb) or gallium (Ga), x=0.01-0.05, y=0.15-0.5. Weighing aluminum oxide, yttrium oxide, cerium oxide and rare earth oxide according to the chemical formula ratio, and adding 1%-5% mole flux at the same time, and mixing them into raw materials for preparing white light phosphor. During the specific operation, weigh Y 2 o 3 : 4.0g, Al 2 o 3 : 3.1g, CeO 2 : 0.3g, NaF: 0.5g, H 3 BO 3 : 0.1g, Gd 2 o 3 : 0.7g, mix and grind for 20-40min, put it into a crucible, and bake it at 1200°C-1550°C for 5 hours in the reducing atmosphere provided by the carbon rod, stop heating and cool down rapidly to get the phosphor. Place in 5% nitric acid aqueous solution, stir well at room temperature for 20-30 minutes, separate the phosphor po...

Embodiment 3

[0015] weigh Y 2 o 3 : 4.0g, Al 2 o 3 : 3.1g, CeO 2 : 0.3g, NaF: 0.5g, H 3 BO 3 : 0.1g, Ga 2 o 3 : 0.2g, mix and grind for 20-40min, put it into a crucible, bake at 1200°C-1550°C for 5 hours in a reducing atmosphere provided by a carbon rod, stop heating and cool rapidly, and place the obtained powder in 5% nitric acid In the aqueous solution, fully stir at room temperature for 20-30 minutes to separate the fluorescent powder, and dry it at 100°C-120°C for 1 hour to obtain a high-brightness fluorescent powder with a blue-shifted wavelength.

[0016] From attached figure 1 , attached figure 2 And attached image 3 It can be seen that doping with rare earth elements can red-shift or blue-shift the emission wavelength. attached figure 2 It shows that the emission wavelength has different red shifts with the amount of doped gadolinium (Gd). attached image 3 It is shown that the emission wavelength has different blue shifts with the amount of gallium (Ga) doped.

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Abstract

A wavelength adjustable high-brightness fluorescent powder for white LED has a chemical formula: Y3-xAl5O12:xCe3+, where x=0.01-0.05. It is prepared from aluminium oxide, yttrium oxide, cerium oxide and flux through proportionally mixing, grinding, loading the mixture in calcining container, putting the container in furnace and the carbon rod outside the container, heating to 900 deg.C, holding the temp for 30 min, heating to 1550 deg.C, for calcining it and cooling. Its advantages are high light intensity and high dispersity in transparent gel.

Description

Technical field: [0001] The invention relates to a yttrium-aluminum-garnet-type fluorescent powder; in particular, it relates to a preparation method of a high-brightness wavelength-tunable white LED fluorescent powder for blue light-emitting diodes. Background technique: [0002] With the application and development of nitrides as light-emitting diodes (LEDs), a new generation of green and environmentally friendly solid-state lighting sources --- nitride white LEDs have become the focus of attention. White light LEDs have the advantages of low energy consumption, long life, compact structure, small size, planarization, light weight, good directionality, fast response, no radiation, and resistance to various harsh conditions. Therefore, nitride white light LEDs have broad application prospects. A large number of market demands and huge economic benefits. At present, the luminous intensity of phosphor powder used in packaging white LED needs to be improved. The luminous inte...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): C09K11/78
CPCY02B20/181Y02B20/00
Inventor 王晶郑荣儿苗洪利杨爱玲孟继武
Owner OCEAN UNIV OF CHINA
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