CN1730606A - Self-ignite preparation method of spherical nanometer Yttrium europium silicate fluorescent powder - Google Patents
Self-ignite preparation method of spherical nanometer Yttrium europium silicate fluorescent powder Download PDFInfo
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- CN1730606A CN1730606A CN 200510060257 CN200510060257A CN1730606A CN 1730606 A CN1730606 A CN 1730606A CN 200510060257 CN200510060257 CN 200510060257 CN 200510060257 A CN200510060257 A CN 200510060257A CN 1730606 A CN1730606 A CN 1730606A
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Abstract
Disclosed is a self-ignited preparation method of spherical nanometer Yttrium europium silicate fluorescent powder, which comprises using tetraethoxysilane, ethanol, deionized water, nitric acid, yttrium oxide, europium oxide, glycine as raw material to prepare transparent glue, evaporating water content in the gel at 500-700 deg C, calcining 2-3 hours at 1100-1500 deg. C, thus obtaining polycrystalline nano sub-micron yttrium-europium silicate fluorescent powder.
Description
Technical field
The present invention relates to a kind of compound of silicate, particularly a kind of auto-combustion preparation method of ball shaped nano yttrium silicate europium fluorescent material.
Background technology
Existing commercial fluorescent material mostly is that high temperature solid phase synthesis is made, pyroreaction big energy-consuming and size distribution inequality, the powder pattern is different, need to use the method for ball milling to obtain the fluorescent material of 2-8 micron grain size, and ball milling is destroyed crystalline structure, influences luminous intensity, and makes the powder granule size inconsistent, pattern is imperfect, causes the coating inequality.People also use sol-gel method, hydrothermal synthesis method, the complexing gel method, methods such as homogeneous coprecipitation prepare fluorescent material, and these methods can remedy the deficiency of high temperature solid phase synthesis, but preparation process time is long, people such as Lin Jun have invented spray-drying process and have made powder pattern subglobular, and the spherical powder particle shows it is very necessary to high brightness, high definition, can obtain higher tap density, reduce the scattering of twinkler, but still have long problem of preparation technology's time.
The raw material powder of crystalline ceramics requires to have higher purity and dispersiveness, has higher sintering activity, and particle is relatively evenly also spherical in shape, can not condense.Ceramic powder can not meet the demands with traditional solid reaction process preparation, and long with chemical preparation process process times such as chemical precipitation method, sol-gel processings, the cost height.Spray-drying process and auto-combustion method etc. obtain favor in the preparation of the raw material powder of crystalline ceramics recently.
Auto-combustion method has seen preparation Y
2O
3, Y
3Al
5O
12, YVO
4Be the fluorescent material of matrix, these available nitric acid metal-salts and vanadic acid ammonia synthesis add incendiary material glycine or citric acid preparation.But yttrium silicate Y
2SiO
5The fluorescent material of matrix is because the silicon source is a tetraethoxy, and auto-combustion method does not appear in the newspapers always.
Summary of the invention
The object of the present invention is to provide a kind of auto-combustion preparation method of ball shaped nano yttrium silicate europium fluorescent material, use in its raw material with tetraethoxy and be the silicon source, improve the temperature of combustion chamber, the ratio of adjusting silicon and ruthenium ion obtains nanometer, submicron yttrium silicate europium fluorescent material.The preparation process cycle is short, the efficient height, and powder is spherical in shape, the granularity high conformity.
A kind of auto-combustion preparation method of ball shaped nano yttrium silicate europium fluorescent material, the chemical formula of this fluorescent material is (Y
1-xEu
x)
2SiO
5, 0＜X in the formula≤0.4 is characterized in that adopting the following step:
A) analytical pure tetraethoxy, analytical pure raw spirit, deionized water are pressed Si (OC
2H
5)
4: C
2H
6O: H
2O=4: 5: 1 mol ratio proportioning is made pioneer's liquid, and regulating pH value is 2～3, mixes to form homogeneous transparent colloidal sol; B) elder generation is added in nitric acid and makes 30% salpeter solution in the deionized water, respectively join in aqueous nitric acid by stoicheiometry 4N class yttrium oxide and europium sesquioxide again, and heating, stir, make the yttrium nitrate aqueous solution and the europium nitrate aqueous solution, heat transparent and pH value is neutrality; C) with Yttrium trinitrate Y (NO
3)
3The aqueous solution, europium nitrate Eu (NO
3)
3The aqueous solution and glycine Gly solution are by [Y
3++ Eu
3+]: Gly: Si=2.3: 3～7: 1 mol ratio is added drop-wise to steps A lentamente) colloidal sol in, after fully stirring, put into 80 ℃ of water-baths and heat, form clear gel seldom the time to wherein moisture; D) clear gel is placed in the crucible, puts into temperature and be 500 ℃～700 ℃ retort furnace, i.e. burning voluntarily after moisture evaporates fully, with glycine Gly as reductive agent, NO
3 -As oxygenant, carry out exothermic oxidation-reduction reaction, collect loose white powder, promptly be non-crystalline silicon acid yttrium europium powder; E) amorphous yttrium silicate europium powder obtains polycrystalline yttrium silicate europium fluorescent material 1100～1500 ℃ temperature lower calcination 2～3 hours; The temperature of calcining furnace is heated to 400 ℃ by room temperature by the temperature rise rate of 1 ℃/min, after this 100 ℃ of insulations of every rising 30min, be heated to 950 ℃ of insulation 30min, speed by 1 ℃/min is heated to 1100～1500 ℃ of insulations again, the granular size of final holding temperature fluorescent material as required and deciding naturally cools to room temperature subsequently; Final holding temperature when the temperature of the retort furnace when regulating burning and calcining, can obtain the nano-phosphor of different-grain diameter, when the final holding temperature of incinerating is 1100 ℃, the crystal grain median size of fluorescent material is 30～40nm, when the final holding temperature of incinerating was 1500 ℃, the size of microcrystal of fluorescent material was 100～150nm.
Under the different condition size of the fluorescent material of gained and crystalline phase analysis see the following form (Ln=Y, Eu):
Table 1
| Ln 3+∶Si 3+ | Si 3+∶Gly | Furnace temperature (℃) | Calcining temperature (℃) and the time (h) | Average crystal grain particle diameter (nm) | Crystalline phase |
| 2.0∶1 2.2∶1 2.3∶1 2.3∶1 2.3∶1 2.3∶1 2.3∶1 2.3∶1 | 1∶5 1∶5 1∶3 1∶5 1∶7 1∶5 1∶5 1∶5 | 600 700 700 500 700 700 700 700 | 950/3 950/2 950/3 950/3 950/2 1100/3 1300/3 1500/3 | 25 26 29 31 30 39 84 103 | X 1 X 1 X 1 X 1 X 1 X 1 X 2 X 2 |
Composition proportion in the table 1 is a mol ratio.
As [Y
3++ Eu
3+]: [Si] is strict when press the chemical equation proportioning, easily the miscellaneous on a small quantity (Y of formation
2Si
2O
7And Y
4.67(SiO
4)
3O), need to increase Y
3+Content, with [Y
3++ Eu
3+]: [Si]=2.3: 1 is good.Furnace temperature is lower than 500 ℃, can not perfect combustion, but still can form nanocrystalline through calcining.
The europium activated phosphor that contains silica-based multivariant oxide matrix of the present invention's preparation has spherical morphology, particle size distribution range is little, particle diameter is controlled at 20nm～150nm, can control particle diameter by ratio, calcining temperature and the time of selecting suitable furnace temperature, glycine.
With prior art relatively, advantage of the present invention is: 1) particle is bordering on sphere, can obtain higher tap density, reduces the scattering of twinkler; 2) granular size is controlled; 3) narrow diameter distribution, more simple to operate than spray pyrolysis, the amount of single job is bigger; 4) sintering temperature is lower than solid-phase synthesis, and the time is short, save energy; 5) control and sintering temperature, the control of time through the burning furnace temperature can obtain close with micropowder and the red fluorescent material coating excellent property of fluorescence intensity.
Description of drawings
Fig. 1 is the XRD crystalline phase analysis chart of the fluorescent material after embodiment 1 calcining, according to 1996JCPDS41-0004 standard card data, as can be seen with this card meet better, burning back crystal is in X
1Crystalline phase shows to generate Eu: Y
2SiO
5
150,000 times of transmission electron microscope photo demonstration figure of the fluorescent material that Fig. 2 makes for embodiment 1.
The emmission spectrum figure of the fluorescent material that Fig. 3 makes for embodiment 1 under 396nm ultraviolet excitation condition, the emission peak wavelength is positioned at the 612nm place, belongs to Eu
3+ 5D
0→
7F
2Transition.
Fig. 4 is the infrared absorpting light spectra of fluorescent material, adopts and mixes the KBr compressing tablet of 1% samples of nanopowders, makes in 3 hours through 140 ℃ of bakings.Y (Eu)-O key absorption peak is positioned at 559.36cm
-1The place, the Si-O absorption peak is positioned at 1024.2cm
-1The place.
Fig. 5 is that embodiment 1 fluorescent material measured atomic force microscope photo after supersound process shows three-dimensional plot.
Fig. 6 is that embodiment 1 fluorescent material measured atomic force microscope photo after supersound process shows X-Y scheme.
Embodiment
Embodiment 1:
A kind of auto-combustion preparation method of ball shaped nano yttrium silicate europium fluorescent material, 5%Eu, Y: Si=2.3: 1, Si: Gly=1: 5,700 ℃ of furnace temperature, 1300 ℃-3h of calcining.
Take by weighing 1.5944 gram Si (OC
2H
5)
4, add 1.7276 gram C successively
2H
6O and 0.2701 gram H
2O, and drip nitric acid HNO
3, regulating pH value is 2～3, forms homogeneous transparent colloidal sol behind the stirring 40min.Add 2.8160 gram Gly again, drip the Y (NO of 16.4m l successively
3)
3(0.001mol/ml), the Eu (NO of 4.3ml
3)
3(0.0002mol/ml) solution, fully stir 40min after, in 80 ℃ of water-baths, heat 1.5h, form clear gel.Put it in the crucible, in 700 ℃ retort furnace, continue heating then.During the moisture evaporate to dryness, temperature sharply rises, and keeps burning after the spontaneous combustion, and is complete up to all reactant reactions, and collecting the product that obtains promptly is nano amorphous powder Eu: Y
2SiO
5In order to improve nano-powder Eu: Y
2SiO
5Luminescent properties, it is carried out high-temperature calcination handles, calcination process is: sample is heated to 400 ℃ by room temperature by the temperature rise rate of 1 ℃/min in retort furnace, 100 ℃ of insulations of every rising 30min is heated to 950 ℃ of insulation 30min, temperature rise rate by 1 ℃/min is heated to 1300 ℃, be incubated 3 hours, the polycrystal powder average crystal grain directly is 84nm.
Fig. 1 is the XRD crystalline phase analysis chart of this fluorescent material.
Fig. 2 is that 150,000 times of transmission electron microscope photos of this fluorescent material show figure.
Fig. 3 is the emmission spectrum figure of this fluorescent material under 396nm ultraviolet excitation condition.
Fig. 4 is the infrared absorpting light spectra of this fluorescent material.
Fig. 5 is that this fluorescent material measured atomic force microscope photo after supersound process shows three-dimensional plot.
Fig. 6 is that this fluorescent material measured atomic force microscope photo after supersound process shows X-Y scheme.
Embodiment 2:
A kind of auto-combustion preparation method of ball shaped nano yttrium silicate europium fluorescent material, 40%Eu, Y: Si=2: 1, Si: Gly=1: 5,700 ℃ of furnace temperature, 1100 ℃-3h of calcining.
Take by weighing 1.7032 gram Si (OC
2H
5)
4, add 1.8583 gram C successively
2H
6O and 0.3019 gram H
2O, and drip nitric acid HNO
3, regulating pH value is 2～3, forms homogeneous transparent colloidal sol behind the stirring 40min.Add 3.0033 gram Gly again, drip the Y (NO of 14.4ml successively
3)
3(0.001mol/ml), the Eu (NO of 8ml
3)
3(0.0002mol/ml) solution, after stirring 40min, in 80 ℃ of water-baths, heat 1.5h, in 700 ℃ retort furnace, continue to be heated to that to be burned to reactant reaction complete then, the product that collection obtains carries out the process of high-temperature calcination processing with embodiment 1, final holding temperature is 1100 ℃, is incubated 3 hours, and the polycrystal powder average crystal grain directly is 39nm.
Embodiment 3:
A kind of auto-combustion preparation method of ball shaped nano yttrium silicate europium fluorescent material, 5%Eu, Y: Si=2.3: 1, Si: Gly=1: 3,700 ℃ of furnace temperature, 1500 ℃-3h of calcining.
Take by weighing 1.0598 gram Si (OC
2H
5)
4, add 1.1544 gram C successively
2H
6O and 0.1801 gram H
2O, and drip nitric acid HNO
3, regulating pH value is 2～3.Form homogeneous transparent colloidal sol after fully stirring 40min.Add 1.1265 gram Gly again, drip the Y (NO of 8.5ml successively
3)
3(0.001mol/ml), the Eu (NO of 11.5ml
3)
3(0.0002mol/ml) solution behind the stirring 40min, heats 1.5h in 80 ℃ of water-baths, the spontaneous combustion that in 700 ℃ retort furnace, heats up then, and as follows embodiment 1, final holding temperature is 1500 ℃, is incubated 3 hours, the polycrystal powder average crystal grain directly is 103nm.
Embodiment 4
A kind of auto-combustion preparation method of ball shaped nano yttrium silicate europium fluorescent material, 5%Eu, Y: Si=2.3: 1, Si: Gly=1: 5,500 ℃ of furnace temperature, 1000 ℃-3h of calcining.
Take by weighing 1.43496 gram Si (OC
2H
5)
4, add 1.5548 gram C successively
2H
6O and 0.2431 gram H
2O, and drip nitric acid HNO
3, regulating pH value is 2～3.Form homogeneous transparent colloidal sol after fully stirring 40min.Add 2.5344 gram Gly again, drip the Y (NO of 14.8ml successively
3)
3(0.001mol/ml), the Eu (NO of 3.8ml
3)
3(0.0002mol/ml) solution, fully stir 40min after, in 80 ℃ of water-baths, heat 1.5h, form clear gel.Put it in the crucible, in 500 ℃ stove, continue heating then.During the moisture evaporate to dryness, temperature sharply rises, reach the certain temperature spontaneous combustion after, keep burning voluntarily, complete up to all reactant reactions, collecting the product obtain promptly is nano amorphous powder Eu: Y
2SiO
5In order to improve nano-powder Eu: Y
2SiO
5Luminescent properties, it is carried out high-temperature calcination handles, sintering process is: sample is heated to 400 ℃ by room temperature by the temperature rise rate of 1 ℃/min in retort furnace, 100 ℃ of insulations of every rising 30min, be heated to 950 ℃ of insulation 30min, be heated to 1100 ℃ and be incubated 3 hours by the temperature rise rate of 1 ℃/min.The polycrystal powder average crystal grain directly is 40nm.
Claims (2)
1. the auto-combustion preparation method of a ball shaped nano yttrium silicate europium fluorescent material, the chemical formula of this fluorescent material is (Y
1-xEu
x)
2SiO
5, 0＜X in the formula≤0.4 is characterized in that adopting the following step:
A) analytical pure tetraethoxy, analytical pure raw spirit, deionized water are pressed Si (OC
2H
5)
4: C
2H
6O: H
2O=4: 5: 1 mol ratio proportioning is made pioneer's liquid, and regulating pH value is 2～3, mixes to form homogeneous transparent colloidal sol;
B) elder generation is added in nitric acid and makes 30% salpeter solution in the deionized water, respectively join in aqueous nitric acid by stoicheiometry 4N class yttrium oxide and europium sesquioxide again, and heating, stir, make the yttrium nitrate aqueous solution and the europium nitrate aqueous solution, be heated to transparent and pH value is neutral;
C) with Yttrium trinitrate Y (NO
3)
3The aqueous solution, europium nitrate Eu (NO
3)
3The aqueous solution and glycine Gly solution are by [Y
3++ Eu
3+]: Gly: Si=2.3: 3～7: 1 mol ratio is added drop-wise to steps A lentamente) colloidal sol in, after fully stirring, put into 80 ℃ of water-baths and heat, form clear gel seldom the time to wherein moisture;
D) clear gel is placed in the crucible, puts into temperature and be 500 ℃～700 ℃ retort furnace (temperature of retort furnace is lower than 500 ℃ can not burn, and being higher than 800 ℃ of crucibles can split), i.e. burning voluntarily after moisture evaporates fully, with glycine (Gly) as reductive agent, NO
3 -As oxygenant, carry out exothermic oxidation-reduction reaction, collect loose white powder, promptly be non-crystalline silicon acid yttrium europium powder;
E) amorphous yttrium silicate europium powder was calcined 2～3 hours down at 1100～1500 ℃, obtained polycrystalline yttrium silicate europium fluorescent material.
2. auto-combustion preparation method according to claim 1, it is characterized in that: the temperature of calcining furnace is heated to 400 ℃ by room temperature by the temperature rise rate of 1 ℃/min, after this 100 ℃ of insulations of every rising 30min, be heated to 950 ℃ of insulation 30min, speed by 1 ℃/min is heated to 1100～1500 ℃ of insulations again, the granular size of final holding temperature fluorescent material as required and deciding naturally cools to room temperature subsequently.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105754599A (en) * | 2016-03-10 | 2016-07-13 | 华北水利水电大学 | Monoclinic-system-structured superfine white nano fluorescent powder and preparation method thereof |
| CN108191213A (en) * | 2017-12-06 | 2018-06-22 | 常州市丰瑞电子有限公司 | A kind of preparation method of composite fluorescence cloche |
| CN112300798A (en) * | 2020-10-30 | 2021-02-02 | 东台市天源光电科技有限公司 | High-color-rendering environment-friendly red fluorescent powder and preparation method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06287551A (en) * | 1993-04-06 | 1994-10-11 | Mitsubishi Electric Corp | Phosphor and its production |
| CN1102170C (en) * | 1999-10-29 | 2003-02-26 | 重庆大学 | Combustion process for preparing long-afterglow phosphorescent powder |
| CN1226382C (en) * | 2003-06-18 | 2005-11-09 | 中山大学 | Short-afterglow zinc-manganese silicate green fluorescent powder and its preparing method |
| CN100392041C (en) * | 2003-08-05 | 2008-06-04 | 北京大学 | Rare earth activated Y2SiO5 fluorescent powder, and its preparing method and use |
| CN1249198C (en) * | 2003-10-09 | 2006-04-05 | 中国科学院上海硅酸盐研究所 | Perofskite aluminic gadolinium-base fluorescent powder and preparing method thereof |
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2005
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105754599A (en) * | 2016-03-10 | 2016-07-13 | 华北水利水电大学 | Monoclinic-system-structured superfine white nano fluorescent powder and preparation method thereof |
| CN108191213A (en) * | 2017-12-06 | 2018-06-22 | 常州市丰瑞电子有限公司 | A kind of preparation method of composite fluorescence cloche |
| CN108191213B (en) * | 2017-12-06 | 2021-01-05 | 霖鼎光学(上海)有限公司 | Preparation method of composite fluorescent glass cover |
| CN112300798A (en) * | 2020-10-30 | 2021-02-02 | 东台市天源光电科技有限公司 | High-color-rendering environment-friendly red fluorescent powder and preparation method thereof |
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