CN106833614B - The preparation method of quantum dot composite fluorescent powder - Google Patents
The preparation method of quantum dot composite fluorescent powder Download PDFInfo
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- CN106833614B CN106833614B CN201710154028.4A CN201710154028A CN106833614B CN 106833614 B CN106833614 B CN 106833614B CN 201710154028 A CN201710154028 A CN 201710154028A CN 106833614 B CN106833614 B CN 106833614B
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Abstract
The preparation method of quantum dot composite fluorescent powder, is related to fluorescent powder.The raw material halogenation lead compound or halogenation tin compound and methyl ammonium halide or carbonamidine halogen acid salt of quantum dot will be prepared, is dissolved in intensive polar solvent, obtains solution A；High molecular polymer is added in solution A, forms precursor solution after dissolution；Precursor solution is spray-dried, in spray-drying process, precursor solution is dispersed into drop, intensive polar solvent is volatilized out so that drop becomes spheric granules, the ion stayed in high molecular polymer spheric granules occurs reaction in-situ and forms quantum dot, and it is covered by high molecular polymer spheric granules to get quantum dot composite fluorescent powder.During the solvent of spray drying removal, the quantum dot fluorescence material of fabricated in situ quantum dot fluorescence material, synthesis is evenly coated in high molecular polymer substrate, and any post-processing is not necessarily to, it can be realized and quantum dot fluorescence material is coated in the oxygen barrier substrate of water proof, simple process.
Description
Technical field
The present invention relates to fluorescent powders, more particularly, to the preparation method of quantum dot composite fluorescent powder.
Background technique
LED has the remarkable advantages such as energy-saving and environmental protection, safe, small in size, the service life is long, rich in color, reliable performance, will be at
For in artificial light sources history after Edison invented electric light most important revolution.LED is usually blue chip combination fluorescence
Powder realizes white light.Fluorescent powder used includes the nitride of the aluminate of yellowish green optical band, silicate fluorescent powder and red spectral band
Fluorescent powder.Nitride phosphor, due to needing high vacuum, super high sintering temperature, cost is very high；And the halfwidth of its fluorescence spectrum
It is very wide, cause about 20% feux rouges fluorescence to fall in human eye vision of the wavelength greater than 670nm without response spectrum region, causes energy
Waste.Quantum dot fluorescence material has the characteristics that fluorescence spectrum narrow bandwidth, any wavelength fluorescent of visible light wave range can be achieved,
It is considered as the ideal chose for substituting conventional fluorescent powder.By combining the quantum dot fluorescence material of multi-wavelength, height may be implemented
The white light LEDs scheme of colour rendering index, high photosynthetic efficiency.But the major defect of quantum dot fluorescence material is oxygen attack not resistant to water,
Using when must water proof it is oxygen barrier.
United States Patent (USP) US8697471 discloses a kind of scheme that quantum dot fluorescent material is applied in LCD TV backlight source,
In the polymer by synthetic quantum dot fluorescence material cladding, then lower surface covers the oxygen-impermeable macromolecule of water proof on polymer
Thin polymer film.European patent EP 2481100 discloses a kind of method using quantum dot fluorescent material, by synthetic quantum dot
Fluorescent material, which is coated in first polymer, forms composite phosphor, then composite phosphor is coated into other substrates, to reach
To the reinforcement oxygen-impermeable purpose of water proof.The common drawback of above technical scheme is, faces the organic of quantum dot fluorescence material surface
Ligand is difficult to polymer property deterioration compatible with the polymer for coating it, or even causing to coat it, it is caused to be difficult to reach and have
The water proof oxygen barrier property and long-term reliability of effect.European patent EP 3032294 discloses a kind of side using quantum dot fluorescent material
Synthetic quantum dot fluorescence material is modified by method, one layer of Bipolar Polymer of scion grafting on its surface ligand, improve with
Coat the compatibility between its polymer.The shortcomings that changing scheme is that modified technique is complicated, and is difficult to ensure glimmering to quantum dot
The uniform cladding of luminescent material easily causes quantum dot fluorescence material to reunite, and reduces fluorescence quantum efficiency.In consideration of it, it is necessary to provide
A kind of quantum dot composite fluorescent material preparation method of simple process.
Summary of the invention
The purpose of the present invention is to provide for overcoming the water proof faced in existing quantum dot fluorescent material application oxygen barrier tired
The preparation method of difficult and complex process problem quantum dot composite fluorescent powder.
The present invention the following steps are included:
1) the raw material halogenation lead compound or halogenation tin compound and methyl ammonium halide or carbonamidine hydrogen halogen of quantum dot will be prepared
Hydrochlorate is dissolved in intensive polar solvent, obtains solution A；
In step 1), the chemical general formula of the quantum dot is ABX(m)Y(3-m), wherein A=CH3NH3, HC (NH2)2；B=
Pb, Sn；X, Y=Br, Cl, I, 0≤m≤3；The molar concentration of the raw material can be 0.1~0.2mmol/mL；The halogenation leaded
Closing object can be selected from least one of lead bromide, lead chloride, lead iodide etc.；The halogenation tin compound can be selected from stannic bromide, chlorine
Change at least one of tin, stannic iodide etc.；The methyl ammonium halide can be selected from methyl bromide ammonium, ammonio methacrylate, methylpyridinium iodide
At least one of ammonium etc.；The carbonamidine halogen acid salt can be selected from carbonamidine hydrobromate, carbonamidine hydrogen chlorate, carbonamidine hydriodate
At least one of Deng；Dimethylformamide or dimethyl acetamide etc. can be used in the intensive polar solvent.
2) high molecular polymer is added in solution A, forms precursor solution after dissolution；
In step 2), the high molecular polymer can be selected from polyvinylidene fluoride, bisphenol-A glycerine methacrylate
One of ester, polychlorotrifluoroethylene etc.；The additional amount of the high molecular polymer can be 0.15~0.5g/mL.
3) precursor solution for obtaining step 2) is spray-dried, and in spray-drying process, precursor solution is dispersed
At drop, intensive polar solvent is volatilized out so that drop becomes spheric granules, stay in high molecular polymer spheric granules from
Son occurs reaction in-situ and forms quantum dot, and is covered by high molecular polymer spheric granules to get quantum dot composite fluorescent
Powder.
In step 3), the spraying carrier gas can be nitrogen or argon gas, and spraying temperature can be 30~50 DEG C, spraying
Flow≤150m3/h。
The partial size for the quantum dot that the reaction in-situ is formed can be 1~5nm.Of obtained quantum dot composite fluorescent powder
Grain diameter can be 0.1~10 μm.
Using technical solution of the present invention, have the advantages that
During the solvent of spray drying removal, fabricated in situ quantum dot fluorescence material, the quantum dot fluorescence of synthesis
Material is evenly coated in high molecular polymer substrate, is not necessarily to any post-processing, be can be realized quantum dot fluorescence material packet
It is overlying in the oxygen barrier substrate of water proof, simple process；The quantum dot composite fluorescent powder of formation not only has water-fast oxygen attack, but also maintains
The high-quantum efficiency characteristic of quantum dot fluorescence material；The quantum dot composite fluorescent powder of preparation can be directly used for LED encapsulation substitution and pass
The fluorescent powder of system, using simplicity.
Detailed description of the invention
Fig. 1 is that observation gained is coated on the quantum dot distribution situation picture in quantum dot composite fluorescent powder under transmission electron microscope.
Fig. 2 is that observation gained is coated on the quantum dot pattern picture in quantum dot composite fluorescent powder under transmission electron microscope.
Specific embodiment
Following embodiment will the present invention is further illustrated in conjunction with attached drawing.
Embodiment 1
A kind of preparation method of quantum dot composite fluorescent powder, the chemical formula of the quanta point material are CH3NH3PbBr3, institute
State method the following steps are included:
(1) the raw material methyl bromide ammonium and lead bromide that prepare quantum dot are weighed according to molar ratio, is dissolved in highly polar
In solvent, stirring forms homogeneous solution, material concentration 0.1mmol/mL；
(2) in a solvent, high molecular polymer is further added, and stirs to dissolve and to form precursor solution, high score
Sub- polymer additional amount is 0.15g/mL；
(3) precursor solution is spray-dried, spraying carrier gas is nitrogen or argon gas, 30 DEG C of vapo(u)rizing temperature, is sprayed
Spray amount 150m3/ h, in spray-drying process, precursor solution is dispersed into drop, intensive polar solvent be volatilized out so that
Drop becomes spheric granules, stays in ion in high molecular polymer spheric granules reaction in-situ occurs and form quantum dot, and by
It is coated in high molecular polymer spheric granules, referring to Fig. 1, to complete the preparation of quantum dot composite phosphor.
The intensive polar solvent is dimethylformamide.
The quantum dot that the reaction in-situ is formed, partial size is in 5nm.Referring to fig. 2, the observation gained amount of being coated under transmission electron microscope
Quantum dot pattern picture in son point composite phosphor.
The quantum dot composite fluorescent powder, particle diameter is at 10 μm.
The high molecular polymer is polyvinylidene fluoride.
Embodiment 2
A kind of preparation method of quantum dot composite fluorescent powder, the chemical formula of the quanta point material are HC (NH2)2PbI3, system
The raw material carbonamidine hydriodate HC (NH of standby quantum dot2)2I and lead iodide are weighed according to molar ratio, remaining is same as Example 1.
Embodiment 3
A kind of preparation method of quantum dot composite fluorescent powder, the chemical formula of the quanta point material are CH3NH3SnCl3, system
The raw material ammonio methacrylate and stannic chloride of standby quantum dot are weighed according to molar ratio, remaining is same as Example 1.
Embodiment 4
A kind of preparation method of quantum dot composite fluorescent powder, the chemical formula of the quanta point material are CH3NH3SnBr(1)
I(2), it the described method comprises the following steps:
(1) the raw material methyl bromide ammonium of quantum dot, methylpyridinium iodide ammonium, stannic bromide, stannic iodide will be prepared according to molar ratio
It weighs, is dissolved in intensive polar solvent, stirring forms homogeneous solution, material concentration 0.2mmol/mL；
(2) in a solvent, high molecular polymer is further added, and stirs to dissolve and to form precursor solution, high score
Sub- polymer additional amount is 0.5g/mL；
(3) precursor solution being spray-dried, spraying carrier gas is nitrogen or argon gas, 50 DEG C of vapo(u)rizing temperature,
Mist flow 150m3/h。
The intensive polar solvent is dimethyl acetamide.
The quantum dot that the reaction in-situ is formed, partial size is 1.
The quantum dot composite fluorescent powder, particle diameter is at 0.1 μm.
The high molecular polymer is bisphenol-A glycerine double methyl methacrylate.
Remaining is same as Example 1.
Embodiment 5
A kind of preparation method of quantum dot composite fluorescent powder, the chemical formula of the quanta point material are HC (NH2)2PbCl(2)
Br(1), the method comprises the following steps:
(1) the raw material carbonamidine hydrobromate HC (NH of quantum dot will be prepared2)2Br, carbonamidine hydrogen chlorate HC (NH2)2Cl, chlorine
Change lead or lead bromide is weighed according to molar ratio, be dissolved in intensive polar solvent, stirring forms homogeneous solution, and material concentration is
0.15mmol/mL；
(2) in a solvent, high molecular polymer is further added, and stirs to dissolve and to form precursor solution, high score
Sub- polymer additional amount is 0.3g/mL；
(3) precursor solution being spray-dried, spraying carrier gas is nitrogen or argon gas, 40 DEG C of vapo(u)rizing temperature,
Mist flow 100m3/h。
The intensive polar solvent is dimethyl acetamide.
The quantum dot that the reaction in-situ is formed, partial size is in 3nm.
The quantum dot composite fluorescent powder, particle diameter is at 5 μm.
The high molecular polymer is polychlorotrifluoroethylene.
Remaining is same as Example 1.
Embodiment 6
A kind of preparation method of quantum dot composite fluorescent powder, the quantum dot have perovskite structure, chemical formula HC
(NH2)2SnBr(1.5)I(1.5), the method comprises the following steps:
(1) the raw material carbonamidine hydrobromate HC (NH of quantum dot will be prepared2)2Br, carbonamidine hydriodate HC (NH2)2I, bromination
Tin, stannic iodide are weighed according to molar ratio, are dissolved in intensive polar solvent, and stirring forms homogeneous solution, and material concentration is
0.2mmol/mL；
(2) in a solvent, high molecular polymer is further added, and stirs to dissolve and to form precursor solution, high score
Sub- polymer additional amount is 0.4g/mL；
(3) precursor solution being spray-dried, spraying carrier gas is nitrogen or argon gas, 30 DEG C of vapo(u)rizing temperature,
Mist flow 150m3/h。
The high molecular polymer is polyvinylidene fluoride.
Remaining is same as Example 5.
Claims (9)
1. the preparation method of quantum dot composite fluorescent powder, it is characterised in that the following steps are included:
1) the raw material halogenation lead compound or halogenation tin compound and methyl ammonium halide or carbonamidine halogen acid salt of quantum dot will be prepared,
It is dissolved in intensive polar solvent, obtains solution A；The chemical general formula of the quantum dot is ABX(m)Y(3-m), wherein A=CH3NH3, HC
(NH2)2；B=Pb, Sn；X, Y=Br, Cl, I, 0≤m≤3；
2) high molecular polymer is added in solution A, forms precursor solution after dissolution；
3) precursor solution for obtaining step 2) is spray-dried, and in spray-drying process, precursor solution is dispersed into liquid
Drop, intensive polar solvent is volatilized out so that drop becomes spheric granules, and the ion stayed in high molecular polymer spheric granules is sent out
Raw reaction in-situ forms quantum dot, and is covered by high molecular polymer spheric granules to get quantum dot composite fluorescent powder.
2. the preparation method of quantum dot composite fluorescent powder as described in claim 1, it is characterised in that in step 1), the raw material
Molar concentration be 0.1~0.2mmol/mL.
3. the preparation method of quantum dot composite fluorescent powder as described in claim 1, it is characterised in that in step 1), the halogenation
Lead compound is selected from least one of lead bromide, lead chloride, lead iodide.
4. the preparation method of quantum dot composite fluorescent powder as described in claim 1, it is characterised in that in step 1), the halogenation
Tin compound is selected from least one of stannic bromide, stannic chloride, stannic iodide；The methyl ammonium halide is selected from methyl bromide ammonium, first
At least one of ammonium chloride, methylpyridinium iodide ammonium.
5. the preparation method of quantum dot composite fluorescent powder as described in claim 1, it is characterised in that in step 1), the carbonamidine
Halogen acid salt is selected from least one of carbonamidine hydrobromate, carbonamidine hydrogen chlorate, carbonamidine hydriodate.
6. the preparation method of quantum dot composite fluorescent powder as described in claim 1, it is characterised in that in step 1), the strong pole
Property solvent use dimethylformamide or dimethyl acetamide.
7. the preparation method of quantum dot composite fluorescent powder as described in claim 1, it is characterised in that in step 2), the high score
Sub- polymer is selected from one of polyvinylidene fluoride, bisphenol-A glycerine double methyl methacrylate, polychlorotrifluoroethylene.
8. the preparation method of quantum dot composite fluorescent powder as described in claim 1, it is characterised in that in step 2), the high score
The additional amount of sub- polymer is 0.15~0.5g/mL.
9. the preparation method of quantum dot composite fluorescent powder as described in claim 1, it is characterised in that described spraying in step 3)
Carrier gas be nitrogen or argon gas, spraying temperature be 30~50 DEG C, spraying flow≤150m3/h。
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| CN107644926B (en) * | 2017-09-22 | 2019-08-06 | 苏州轻光材料科技有限公司 | A kind of high efficiency preparation method of miniature white light LED part |
| WO2022089617A1 (en) * | 2020-10-30 | 2022-05-05 | 致晶科技（北京）有限公司 | Perovskite quantum dot/polymer composite powder material, preparation method therefor and application thereof |
| CN115717071A (en) * | 2021-08-27 | 2023-02-28 | 北京航空航天大学合肥创新研究院(北京航空航天大学合肥研究生院) | Perovskite quantum dot composite material and preparation method and application thereof |
| CN115991922A (en) * | 2021-10-19 | 2023-04-21 | 北京航空航天大学合肥创新研究院(北京航空航天大学合肥研究生院) | Composite material and preparation method and application thereof |
| CN114217012B (en) * | 2021-11-10 | 2023-09-12 | 中国科学院上海技术物理研究所 | In-situ modification method in mercury system quantum dot traditional heat injection flow |
| CN114316944B (en) * | 2021-12-07 | 2023-11-21 | 西安交通大学 | Method for preparing high-stability zirconia coated quantum dot |
| CN114561206B (en) * | 2022-02-17 | 2023-10-13 | 南方科技大学 | Fluorescent composite material and preparation method and application thereof |
| CN116218106A (en) * | 2023-04-07 | 2023-06-06 | 极电光能有限公司 | Formamidino perovskite/PVDF composite membrane and preparation method and application thereof |
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| CN101544886A (en) * | 2009-05-07 | 2009-09-30 | 哈尔滨工程大学 | Praseodymium-doped calcium titanate luminescent powder and preparation method thereof |
| CN102648536A (en) * | 2009-09-23 | 2012-08-22 | 纳米技术有限公司 | Encapsulated semiconductor nanoparticle - based materials comprising an additive |
| US8697471B2 (en) * | 2008-12-30 | 2014-04-15 | Nanosys, Inc. | Methods for encapsulating nanocrystals and resulting compositions |
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| US8697471B2 (en) * | 2008-12-30 | 2014-04-15 | Nanosys, Inc. | Methods for encapsulating nanocrystals and resulting compositions |
| CN101544886A (en) * | 2009-05-07 | 2009-09-30 | 哈尔滨工程大学 | Praseodymium-doped calcium titanate luminescent powder and preparation method thereof |
| CN102648536A (en) * | 2009-09-23 | 2012-08-22 | 纳米技术有限公司 | Encapsulated semiconductor nanoparticle - based materials comprising an additive |
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