Single-phase white-emitting phosphor based on near ultraviolet excitation and preparation method thereof

Abstract

The invention relates to phosphor applicable to preparing a light emitting[white-emitting] LED, in particular to single-phase white-emitting phosphor based on near ultraviolet excitation and a preparation method thereof; the chemical formula of the phosphor is as follows: Sr5-m-nZn(SiO4)2Cl2:Eum, wherein m is more than or equal to 0.10 but less than or equal to 0.15, n is more than or equal to 0 but less than or equal to 0.20; the phosphor emits single-phase white light after being excited by 360nm-410nm near ultraviolet light. The preparation method comprises the steps of taking SiO2, Eu2O3, SrCO3, ZnO and SrCl2.6H2O as raw materials, mixing and grinding the raw materials, and then baking the raw materials at the temperature of 1000 DEG C to 1200 DEG C for 3h to 5h, and grinding the raw materials after being cooled naturally, thereby obtaining the single-phase white-emitting phosphor. The phosphor can be combined with near ultraviolet tube core to prepare the light emitting LED, thus overcoming the defects of tricolor (red, green and blue) mixed phosphor that the problems of re-absorption and proportioning regulation affect the lumen efficiency and color rendition.

Description

technical field

[0001] The invention relates to a fluorescent powder suitable for preparing white light LEDs, in particular to a fluorescent powder emitting single-phase white light under excitation of near-ultraviolet light and a preparation method thereof. Background technique

[0002] The successful development of high-brightness GaN blue light-emitting diodes and the resulting white LEDs are known as the biggest light source revolution since Edison invented the incandescent lamp. Compared with traditional incandescent lamps and fluorescent lamps, white LED lighting has attracted much attention due to its advantages of high efficiency, energy saving, long life, no (Hg, Pb) pollution, low working voltage, and not easily damaged. In recent years, the LED industry has been increasing at a rate of more than 20% every year.

[0003] Blue (purple) LED phosphor combination is an important way to realize white LED. At present, the practical white LEDs on the market are YAG:Ce y...

Examples

Embodiment 1

[0019] Preparation of Sr 4.90 (SiO 4 ) 2 Cl 2.0 :Eu 2+ 0.10 (i.e. when Sr 5-m-n Zn n (SiO 4 ) 2 Cl 2 :Eu 2+ m When m=0.10, n=0.00) phosphor.

[0020] Weigh SrCO according to stoichiometric ratio 3 2.8782 g, SrCl 2 .6H 2 O1.5972 grams [due to SrCl 2 .6H 2 O has a low melting point (873°C), and the calculated excess is 20%], SiO 2 0.6008 g, Eu 2 o 3 0.0880 g, put it into an agate mortar and grind it; put it into a corundum crucible, cover it, put it in a high-temperature furnace, under CO or H 2 Under a reducing atmosphere, burn at a temperature of 1100-1200°C for 3-5 hours; after natural cooling and grinding, the chemical formula is 8r 4.90 (SiO 4 ) 2 Cl 2.0 :Eu 0.10 single-phase white phosphors. Its color coordinates are x=0.3262, y=0.4386; the color temperature is T c =5710K; the color rendering index is Ra=56.0.

Embodiment 2

[0022] Preparation of Sr 4.70 Zn 0.20 (SiO 4 ) 2 Cl 2 :Eu 0.10 2+ (i.e. when Sr 5-m-n Zn n (SiO 4 ) 2 Cl 2 :Eu 2+ m When m=0.10, n=0.20) phosphor.

[0023] Weigh SrCO according to stoichiometric ratio 3 2.7306 g, SrCl 2 .6H 2 O 1.4641 grams [according to the calculated amount in excess of 10%], ZnO0.0814, SiO 2 0.6008 g, Eu 2 o 3 0.0880 g, put it into an agate mortar and grind it; put it into a corundum crucible, cover it, put it in a high-temperature furnace, under CO or H 2 Under reducing atmosphere, burn at 1100-1200°C for 3-5 hours; after natural cooling, grind to obtain the chemical formula Sr 4.70 Zn 0.20 (SiO 4 ) 2 Cl 2 :Eu 0.10 2+ single-phase white phosphors. Its color coordinates are x=0.3293, y=0.4061; the color temperature is T c =5829K; the color rendering index is Ra=64.0. .

Embodiment 3

[0025] Preparation of Sr 4.88 (SiO 4 ) 2 Cl 2 .:Eu 2+ 0.12 (i.e. when Sr 5-m-n Znn (SiO 4 ) 2 Cl 2 :Eu 2+ m When m=0.12, n=0.00) phosphor.

[0026] Weigh SrCO according to stoichiometric ratio 3 2.8634 g, SrCl 2 .6H 2 O 1.5972 g [20% excess calculated], SiO 2 0.6008 g, Eu 2 o 3 0.1056 g, put it into an agate mortar and grind it; put it into a corundum crucible, cover it, put it in a high-temperature furnace, and burn it at 1100-1200°C for 3-5 hours in a reducing atmosphere of CO or H2; naturally Grinding after cooling, the chemical formula is Sr 4.88 (SiO 4 ) 2 Cl 2 .:Eu 2+ 0.12 single-phase white phosphors. Its color coordinates are x=0.3370, y=0.4074; the color temperature is T c =6067K; the color rendering index is Ra=61.7.

technical field

[0001] The invention relates to a fluorescent powder suitable for preparing white light LEDs, in particular to a fluorescent powder emitting single-phase white light under excitation of near-ultraviolet light and a preparation method thereof. Background technique

[0002] The successful development of high-brightness GaN blue light-emitting diodes and the resulting white LEDs are known as the biggest light source revolution since Edison invented the incandescent lamp. Compared with traditional incandescent lamps and fluorescent lamps, white LED lighting has attracted much attention due to its advantages of high efficiency, energy saving, long life, no (Hg, Pb) pollution, low working voltage, and not easily damaged. In recent years, the LED industry has been increasing at a rate of more than 20% every year.

[0003] Blue (purple) LED phosphor combination is an important way to realize white LED. At present, the practical white LEDs on the market are YAG:Ce y...

Examples

Embodiment 1

[0019] Preparation of Sr 4.90 (SiO 4 ) 2 Cl 2.0 :Eu 2+ 0.10 (i.e. when Sr 5-m-n Zn n (SiO 4 ) 2 Cl 2 :Eu 2+ m When m=0.10, n=0.00) phosphor.

[0020] Weigh SrCO according to stoichiometric ratio 3 2.8782 g, SrCl 2 .6H 2 O1.5972 grams [due to SrCl 2 .6H 2 O has a low melting point (873°C), and the calculated excess is 20%], SiO 2 0.6008 g, Eu 2 o 3 0.0880 g, put it into an agate mortar and grind it; put it into a corundum crucible, cover it, put it in a high-temperature furnace, under CO or H 2 Under a reducing atmosphere, burn at a temperature of 1100-1200°C for 3-5 hours; after natural cooling and grinding, the chemical formula is 8r 4.90 (SiO 4 ) 2 Cl 2.0 :Eu 0.10 single-phase white phosphors. Its color coordinates are x=0.3262, y=0.4386; the color temperature is T c =5710K; the color rendering index is Ra=56.0.

Embodiment 2

[0022] Preparation of Sr 4.70 Zn 0.20 (SiO 4 ) 2 Cl 2 :Eu 0.10 2+ (i.e. when Sr 5-m-n Zn n (SiO 4 ) 2 Cl 2 :Eu 2+ m When m=0.10, n=0.20) phosphor.

[0023] Weigh SrCO according to stoichiometric ratio 3 2.7306 g, SrCl 2 .6H 2 O 1.4641 grams [according to the calculated amount in excess of 10%], ZnO0.0814, SiO 2 0.6008 g, Eu 2 o 3 0.0880 g, put it into an agate mortar and grind it; put it into a corundum crucible, cover it, put it in a high-temperature furnace, under CO or H 2 Under reducing atmosphere, burn at 1100-1200°C for 3-5 hours; after natural cooling, grind to obtain the chemical formula Sr 4.70 Zn 0.20 (SiO 4 ) 2 Cl 2 :Eu 0.10 2+ single-phase white phosphors. Its color coordinates are x=0.3293, y=0.4061; the color temperature is T c =5829K; the color rendering index is Ra=64.0. .

Embodiment 3

[0025] Preparation of Sr 4.88 (SiO 4 ) 2 Cl 2 .:Eu 2+ 0.12 (i.e. when Sr 5-m-n Znn (SiO 4 ) 2 Cl 2 :Eu 2+ m When m=0.12, n=0.00) phosphor.

[0026] Weigh SrCO according to stoichiometric ratio 3 2.8634 g, SrCl 2 .6H 2 O 1.5972 g [20% excess calculated], SiO 2 0.6008 g, Eu 2 o 3 0.1056 g, put it into an agate mortar and grind it; put it into a corundum crucible, cover it, put it in a high-temperature furnace, and burn it at 1100-1200°C for 3-5 hours in a reducing atmosphere of CO or H2; naturally Grinding after cooling, the chemical formula is Sr 4.88 (SiO 4 ) 2 Cl 2 .:Eu 2+ 0.12 single-phase white phosphors. Its color coordinates are x=0.3370, y=0.4074; the color temperature is T c =6067K; the color rendering index is Ra=61.7.

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