CN104293352A - Phosphate blue fluorescent powder for white-light LED (Light-Emitting Diode) and preparation method thereof - Google Patents
Phosphate blue fluorescent powder for white-light LED (Light-Emitting Diode) and preparation method thereof Download PDFInfo
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- CN104293352A CN104293352A CN201410522279.XA CN201410522279A CN104293352A CN 104293352 A CN104293352 A CN 104293352A CN 201410522279 A CN201410522279 A CN 201410522279A CN 104293352 A CN104293352 A CN 104293352A
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- fluorescent powder
- blue fluorescent
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- phosphate
- blue
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
- Y02B20/00—Energy efficient lighting technologies, e.g. halogen lamps or gas discharge lamps
Abstract
The invention discloses phosphate blue fluorescent powder for white-light LED (Light-Emitting Diode) and a preparation method for the phosphate blue fluorescent powder. The fluorescent powder is shown in a chemical expression of Ca8-xLa2(PO4)5O2:xEU<2+>; x is between 0.001 and 0.10. A method comprises the following steps: weighing calcium carbonate, calcium hydrophosphate or ammonium dihydrogen phosphate, lanthanum oxide and europium oxide which are used as raw materials according to the chemical metering ratio of Ca8-xLa2(PO4)5O2:xEU<2+>; grinding the raw materials and uniformly mixing; putting the mixture into a crucible; putting the crucible into a high-temperature furnace, sintering at the temperature of 1,250-1,350 DEG C for 3-7 hours under the condition of reducing atmosphere, and cooling to room temperature, so as to obtain the fluorescent powder. The blue fluorescent powder emits the blue light under the excitation of an ultraviolet and purple light chip, and the emission peak value approaches to 450nm. The fluorescent powder is high in dispersibility, uniform in granularity, high in chemical stability and high in luminous efficiency; an excitation band covers an ultraviolet and purple light area, so that the fluorescent powder can be used as blue fluorescent powder for a near ultraviolet LED.
Description
Technical field
The present invention relates to rare earth luminescent material technical field, especially relate to a kind of white light LEDs phosphate blue fluorescent powder and preparation method thereof.
Background technology
White light LEDs is a kind of solid-state semiconductor device converting electrical energy into white light, also known as semiconductor lighting, there is the plurality of advantages such as efficiency is high, volume is little, the life-span is long, safety, low voltage, energy-saving and environmental protection, being regarded as forth generation lighting source after incandescent light, luminescent lamp, high-voltage gas discharging light by people, is the main product in following illumination market.
There is various white light LEDs preparation method at present, wherein blue-light LED chip and yellow fluorescent material combine, blue-light LED chip and red and green fluorescent material combines, purple LED chip and fluorescent material with three basic colour combine these three kinds of methods low with price, prepare the main method simply becoming and prepare white light LEDs.It is that to study also be the most ripe method the earliest that blue-light LED chip and yellow fluorescent material combine, and the white light LEDs luminous efficiency of preparation is considerably beyond incandescent light, but colour rendering index is low, and colour temperature is high, can not use as interior lighting.In order to improve the color developing of white light LEDs, various countries scientist have developed blue-light LED chip and red, green fluorescent material combines and purple LED chip and red, green, blue fluorescent material with three basic colour combine other two kinds of methods realizing white light LEDs.
The emission wavelength of current InGaN chip moves near ultraviolet region, can provide higher excitation energy for fluorescent material, improves the light intensity of white light LEDs further.Because UV-light is invisible, the color of burst of ultraviolel white light LEDs can only be determined by fluorescent material, therefore colour stable, colour rendering index is high, uses near ultraviolet InGaN chip and blue, yellow fluorescent material or becomes the emphasis of current white light LEDs industry development with the scheme that three primary colors fluorescent powder combines to realize white light.Blue colour fluorescent powder is indispensable composition in the program.
LED blue colour fluorescent powder is mainly divided into several large system: sulphide fluorescent material, aluminate fluorescent powder, silicate fluorescent powder, phosphate phosphor and silica-based nitrogen (oxygen) compound fluorescent material.Sulfide blue colour fluorescent powder is as CaLaGa
3s
6o:Eu
2+.Aluminate blue fluorescent powder is as BaMgAl
10o
17: Eu
2+.Silicate blue fluorescent powder is as MSiO
4: Eu
2+(M=Ca, Sr, Ba), Y
2siO
5: Ce
3+, SrAl
2si
2o
8: Eu
2+, M
3mgSi
2o
8: Eu
2+(M=Ba, Sr) etc.Phosphate phosphor is as LiSrPO
4: Eu
2+, KSrPO
4: Eu
2+and SrMg
2(PO
4)
2: Eu
2+deng.Silica-based nitrogen (oxygen) compound blue colour fluorescent powder is as BaSi
2o
2n
2: Eu
2+, Ca
2si
5n
8: Ce
3+and Ba
2si
5n
8: Ce
3+deng.
Summary of the invention
An object of the present invention is to provide a kind of white light LEDs phosphate blue fluorescent powder.
For achieving the above object, the technical solution used in the present invention is: its white light LEDs phosphate blue fluorescent powder has following chemical representation:
Ca
8-xLa
2(PO
4)
5O
2：xEu
2+
In formula, x is 0.001 ~ 0.10.
Another object of the present invention is to provide the preparation method of above-mentioned white light LEDs phosphate blue fluorescent powder, comprises the steps:
Step (1). by chemical formula Ca
8-xla
2(PO
4)
5o
2: xEu
2+stoichiometric ratio take corresponding raw material, described raw material is respectively calcium carbonate, phosphoric acid salt, lanthanum trioxide, europium sesquioxide, and wherein x is 0.001 ~ 0.10;
Described phosphoric acid salt is secondary calcium phosphate or primary ammonium phosphate;
Step (2). above-mentioned raw materials is ground and obtains mixture; This mixture is loaded crucible, is placed in High Temperature Furnaces Heating Apparatus, under reducing atmosphere, 1250 ~ 1350 DEG C of conditions, sinter 3 ~ 7 hours, be finally cooled to normal temperature to obtain white light LEDs phosphate blue fluorescent powder of the present invention.
Described reducing atmosphere is nitrogen and hydrogen mixture or CO atmosphere, and wherein in nitrogen and hydrogen mixture atmosphere, the volume ratio of hydrogen and nitrogen is 1:19.
Compared with prior art, the invention has the beneficial effects as follows:
(1) fluorescent material of the present invention is substrate material with phosphoric acid salt, has chemical stability and good thermal stability, and raw material is inexpensive, be easy to get, the advantages such as sintering temperature is low.Compare sulfide blue colour fluorescent powder, Heat stability is good of the present invention.Compare aluminate blue fluorescent powder, preparation temperature of the present invention is lower than aluminate, and particle is thinner than aluminate, and luminosity is high, luminous efficiency is high and physical and chemical performance is stablized.Compare silicate blue fluorescent powder, grain graininess of the present invention is even, and sintering temperature is low.Compare silica-based nitrogen (oxygen) compound blue colour fluorescent powder, sintering temperature of the present invention is low, and synthesis technique is simple and raw material is cheap and easy to get.
(2) the present invention compares other phosphate blue fluorescent powders (as LiSrPO
4: Eu
2+, KSrPO
4: Eu
2+), avoid with deliquescent alkaline carbonate in high, the exposure air of decomposition temperature.
Accompanying drawing explanation
Fig. 1 is the fluorescent powder exciting light spectrogram of embodiment 1 provided by the invention preparation;
Fig. 2 is the fluorescent powder utilizing emitted light spectrogram of embodiment 1 provided by the invention preparation;
Fig. 3 is the fluorescent powder XRD figure spectrum of embodiment 1 provided by the invention preparation;
Fig. 4 is the fluorescent powder utilizing emitted light spectrogram of embodiment 2 provided by the invention preparation;
Fig. 5 is the fluorescent powder utilizing emitted light spectrogram of embodiment 3 provided by the invention preparation;
Fig. 6 is the fluorescent powder utilizing emitted light spectrogram of embodiment 4 provided by the invention preparation;
Fig. 7 is the fluorescent powder utilizing emitted light spectrogram of embodiment 5 provided by the invention preparation.
Embodiment
Below in conjunction with specific embodiment, the present invention is further analyzed.
Embodiment 1:
Take raw materials of Ca HPO
4(5mol), CaCO
3(2.999mol), La
2o
3(1mol) and Eu
2o
3(0.0005mol), i.e. Ca
2+: La
3+: PO
4 2-: Eu
2+mol ratio is 7.999:2:5:0.001; By abundant for above-mentioned raw materials ground and mixed evenly after, place in corundum crucible, then put into High Temperature Furnaces Heating Apparatus 1350 DEG C of roastings 7 hours under CO atmosphere, after be cooled to normal temperature, obtain phosphate blue fluorescent powder Ca
7.999la
2(PO
4)
5o
2: 0.001Eu
2+.
As can be seen from Figure 1, the fluorescent material excitation spectrum of the present embodiment is a wide range, covers ultraviolet and violet region, and excitation peak is positioned near 360nm, and spectrum peak is high, illustrates that the fluorescent material of the present embodiment effectively can be excited by ultraviolet and purple light chip.When the excitation wavelength of emmission spectrum is 360nm, as can be seen from Figure 2, the broadband blue light being emitted as divalent europium of the fluorescent material of the present embodiment is launched, and emission peak is positioned near 450nm, illustrates that the fluorescent material of the present embodiment is applicable to doing ultraviolet and purple light excited blue colour fluorescent powder.As can be seen from Figure 3, the fluorescent material XRD figure spectrum of the present embodiment shows the d value of product and the Ca of relative intensity variation tendency and standard
8la
2(PO
4)
5o
2standard card (JCPDF:380257) is consistent, illustrates that the fluorescent material purity that the present embodiment synthesizes is higher.
Embodiment 2:
Take raw materials of Ca HPO
4(5mol), CaCO
3(2.995mol), La
2o
3(1mol) and Eu
2o
3(0.0025mol), i.e. Ca
2+: La
3+: PO
4 2-: Eu
2+mol ratio is 7.995:2:5:0.005; By abundant for above-mentioned raw materials ground and mixed evenly after, place in corundum crucible, then put into High Temperature Furnaces Heating Apparatus 1350 DEG C of roastings 3 hours under CO atmosphere, after be cooled to normal temperature, obtain phosphate blue fluorescent powder Ca
7.995la
2(PO
4)
5o
2: 0.005Eu
2+.
The fluorescent material excitation spectrum of the present embodiment is a wide range, covers ultraviolet and violet region, and excitation peak is positioned near 360nm, and spectrum peak is high, illustrates that the fluorescent material of the present embodiment effectively can be excited by ultraviolet and purple light chip.When the excitation wavelength of emmission spectrum is 360nm, as can be seen from Figure 4, the broadband blue light being emitted as divalent europium of the fluorescent material of the present embodiment is launched, and emission peak is positioned near 455nm, illustrates that the fluorescent material of the present embodiment is applicable to doing ultraviolet and purple light excited blue colour fluorescent powder.The fluorescent material XRD figure spectrum display d value of product of the present embodiment and the Ca of relative intensity variation tendency and standard
8la
2(PO
4)
5o
2standard card (JCPDF:380257) is consistent, illustrates that the fluorescent material purity that the present embodiment synthesizes is higher.
Embodiment 3:
Take raw material NH
4h
2pO
4(5mol), CaCO
3(7.99mol), La
2o
3(1mol) and Eu
2o
3(0.005mol), i.e. Ca
2+: La
3+: PO
4 2-: Eu
2+mol ratio is 7.99:2:5:0.01; By abundant for above-mentioned raw materials ground and mixed evenly after, place in corundum crucible, then put into High Temperature Furnaces Heating Apparatus 1250 DEG C of roastings 7 hours under CO atmosphere, after be cooled to normal temperature, obtain phosphate blue fluorescent powder Ca
7.99la
2(PO
4)
5o
2: 0.01Eu
2+.
The fluorescent material excitation spectrum of the present embodiment is a wide range, covers ultraviolet and violet region, and excitation peak is positioned near 360nm, and spectrum peak is high, illustrates that the fluorescent material of the present embodiment effectively can be excited by ultraviolet and purple light chip.When the excitation wavelength of emmission spectrum is 360nm, as can be seen from Figure 5, the broadband blue light being emitted as divalent europium of the fluorescent material of the present embodiment is launched, and emission peak is positioned near 458nm, illustrates that the fluorescent material of the present embodiment is applicable to doing ultraviolet and purple light excited blue colour fluorescent powder.The fluorescent material XRD figure spectrum display d value of product of the present embodiment and the Ca of relative intensity variation tendency and standard
8la
2(PO
4)
5o
2standard card (JCPDF:380257) is consistent, illustrates that the fluorescent material purity that the present embodiment synthesizes is higher.
Embodiment 4:
Take raw material NH
4h
2pO
4(5mol), CaCO
3(7.95mol), La
2o
3(1mol) and Eu
2o
3(0.025mol), i.e. Ca
2+: La
3+: PO
4 2-: Eu
2+mol ratio is 7.95:2:5:0.05; After abundant for above-mentioned raw materials ground and mixed is even, place in corundum crucible, put into High Temperature Furnaces Heating Apparatus again 1300 DEG C of roastings 5 hours under nitrogen and hydrogen mixture atmosphere (volume ratio of nitrogen and hydrogen mixture atmosphere hydrogen and nitrogen is 1:19), after be cooled to normal temperature, obtain phosphate blue fluorescent powder Ca
7.95la
2(PO
4)
5o
2: 0.05Eu
2+.
The fluorescent material excitation spectrum of the present embodiment is a wide range, covers ultraviolet and violet region, and excitation peak is positioned near 360nm, and spectrum peak is high, illustrates that the fluorescent material of the present embodiment effectively can be excited by ultraviolet and purple light chip.When the excitation wavelength of emmission spectrum is 360nm, as can be seen from Figure 6, the broadband blue light being emitted as divalent europium of the fluorescent material of the present embodiment is launched, and emission peak is positioned near 450nm, illustrates that the fluorescent material of the present embodiment is applicable to doing ultraviolet and purple light excited blue colour fluorescent powder.The fluorescent material XRD figure spectrum display d value of product of the present embodiment and the Ca of relative intensity variation tendency and standard
8la
2(PO
4)
5o
2standard card (JCPDF:380257) is consistent, illustrates that the fluorescent material purity that the present embodiment synthesizes is higher.
Embodiment 5:
Take raw materials of Ca HPO
4(5mol), CaCO
3(2.9mol), La
2o
3(1mol) and Eu
2o
3(0.05mol), i.e. Ca
2+: La
3+: PO
4 2-: Eu
2+mol ratio is 7.9:2:5:0.1; After abundant for above-mentioned raw materials ground and mixed is even, place in corundum crucible, then put into High Temperature Furnaces Heating Apparatus under nitrogen and hydrogen mixture atmosphere (volume ratio of nitrogen and hydrogen mixture atmosphere hydrogen and nitrogen is 1:19) 1250 DEG C of roastings 3 hours, after be cooled to normal temperature, obtain phosphate blue fluorescent Ca
7.9la
2(PO
4)
5o
2: 0.1Eu
2+.
The fluorescent material excitation spectrum of the present embodiment is a wide range, covers ultraviolet and violet region, and excitation peak is positioned near 360nm, and spectrum peak is high, illustrates that the fluorescent material of the present embodiment effectively can be excited by ultraviolet and purple light chip.When the excitation wavelength of emmission spectrum is 360nm, as can be seen from Figure 7, the broadband blue light being emitted as divalent europium of the fluorescent material of the present embodiment is launched, and emission peak is positioned near 450nm, illustrates that the fluorescent material of the present embodiment is applicable to doing ultraviolet and purple light excited blue colour fluorescent powder.The fluorescent material XRD figure spectrum display d value of product of the present embodiment and the Ca of relative intensity variation tendency and standard
8la
2(PO
4)
5o
2standard card (JCPDF:380257) is consistent, illustrates that the fluorescent material purity that the present embodiment synthesizes is higher.
Above-described embodiment is used for explaining and the present invention is described, instead of limits the invention, and in the protection domain of spirit of the present invention and claim, any amendment make the present invention and change, all fall into protection scope of the present invention.
Claims (3)
1. a white light LEDs phosphate blue fluorescent powder, is characterized in that this white light LEDs phosphate blue fluorescent powder has following chemical representation Ca
8-xla
2(PO
4)
5o
2: xEu
2+; X is 0.001 ~ 0.10.
2. prepare the method for a kind of white light LEDs phosphate blue fluorescent powder as claimed in claim 1, it is characterized in that the method comprises the following steps:
Step (1). by chemical formula Ca
8-xla
2(PO
4)
5o
2: xEu
2+stoichiometric ratio take corresponding raw material, described raw material is respectively calcium carbonate, phosphoric acid salt, lanthanum trioxide, europium sesquioxide, and wherein x is 0.001 ~ 0.10;
Described phosphoric acid salt is secondary calcium phosphate or primary ammonium phosphate;
Step (2). above-mentioned raw materials is ground and obtains mixture; This mixture is loaded crucible, is placed in High Temperature Furnaces Heating Apparatus, sinter 3 ~ 7 hours under reducing atmosphere, 1250 ~ 1350 DEG C of conditions after, be cooled to normal temperature, obtain white light LEDs phosphate blue fluorescent powder.
3. the preparation method of a kind of white light LEDs phosphate blue fluorescent powder as claimed in claim 2, it is characterized in that described reducing atmosphere is nitrogen and hydrogen mixture or CO atmosphere, wherein in nitrogen and hydrogen mixture atmosphere, the volume ratio of hydrogen and nitrogen is 1:19.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410522279.XA CN104293352A (en) | 2014-09-30 | 2014-09-30 | Phosphate blue fluorescent powder for white-light LED (Light-Emitting Diode) and preparation method thereof |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410522279.XA CN104293352A (en) | 2014-09-30 | 2014-09-30 | Phosphate blue fluorescent powder for white-light LED (Light-Emitting Diode) and preparation method thereof |
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ID=52313316
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|---|---|---|---|
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109053186A (en) * | 2018-10-25 | 2018-12-21 | 东北大学秦皇岛分校 | It is a kind of to determine phosphorus probe with mixing lanthanum solid electrolyte and preparation method thereof |
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| US20120153228A1 (en) * | 2010-12-20 | 2012-06-21 | National Chiao Tung University | Yellow Phosphor Having Oxyapatite Structure, Preparation Method and White Light-Emitting Diode Thereof |
| CN102559185A (en) * | 2010-12-20 | 2012-07-11 | 财团法人交大思源基金会 | Yellow luminescent material with voelckerite structure and preparation method thereof as well as white light-emitting diode device |
-
2014
- 2014-09-30 CN CN201410522279.XA patent/CN104293352A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20120153228A1 (en) * | 2010-12-20 | 2012-06-21 | National Chiao Tung University | Yellow Phosphor Having Oxyapatite Structure, Preparation Method and White Light-Emitting Diode Thereof |
| CN102559185A (en) * | 2010-12-20 | 2012-07-11 | 财团法人交大思源基金会 | Yellow luminescent material with voelckerite structure and preparation method thereof as well as white light-emitting diode device |
Non-Patent Citations (2)
| Title |
|---|
| HAIKUN LIU等: "Synthesis,broad-band absorption and luminescence properties of blue-emitting phosphor Sr8La2(PO4)6O2:Eu2+ for n-UV white-light-emitting diodes", 《CERAMICS INTERNATIONAL》 * |
| MENGMENG SHANG等: "Blue Emitting Ca8La2(PO4)6O2:Ce3+/Eu2+ Phosphors with High Color Purity and Brightness for White LED: Soft-Chemical Synthesis, Luminescence, and Energy Transfer Properties", 《THE JOURNAL OF PHYSICAL CHEMISTRY C》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109053186A (en) * | 2018-10-25 | 2018-12-21 | 东北大学秦皇岛分校 | It is a kind of to determine phosphorus probe with mixing lanthanum solid electrolyte and preparation method thereof |
| CN109053186B (en) * | 2018-10-25 | 2021-06-15 | 东北大学秦皇岛分校 | Lanthanum-doped solid electrolyte for phosphorus determination probe and preparation method thereof |
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Application publication date: 20150121 |