The preparation method of quantum dot composite fluorescent powder
Technical field
The present invention relates to fluorescent material, more particularly, to the preparation method of quantum dot composite fluorescent powder.
Background technology
LED has the remarkable advantages such as energy-saving and environmental protection, safety, small volume, long lifespan, rich color, dependable performance, will be into
For in artificial light sources history after Edison invented electric light most important revolution.LED is typically blue chip combined with fluorescent
Powder, realizes white light.Fluorescent material used includes the nitride of the aluminate, silicate fluorescent powder and red spectral band of yellowish green optical band
Fluorescent material.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 more than 670nm without response spectrum region, cause energy
Waste.Quantum dot fluorescence material, with fluorescence spectrum narrow bandwidth, be capable of achieving any wavelength fluorescent of visible light wave range the features such as,
It is considered as the ideal chose for substituting conventional fluorescent powder.By the quantum dot fluorescence material for combining multi-wavelength, it is possible to achieve high
The white light LEDs scheme of colour rendering index, specular removal.But, the major defect of quantum dot fluorescence material is to be corroded intolerant to water oxygen, its
Using when must water proof oxygen barrier.
United States Patent (USP) US8697471 discloses a kind of scheme of the application quantum dot fluorescent material in LCD TV backlight source,
Synthetic quantum dot fluorescence material is coated in the polymer, then lower surface covers the macromolecule of water proof oxygen barrier on polymer
Thin polymer film.European patent EP 2481100 discloses a kind of method of application quantum dot fluorescent material, by synthetic quantum dot
Fluorescent material forms composite phosphor in being coated on first polymer, then composite phosphor is coated into other base materials, to reach
To the purpose for strengthening water proof oxygen barrier.The common drawback of above technical scheme is face quantum dot fluorescence material surface organic
Part is difficult to and coats its polymer-compatible, or even causes to coat its polymer property and deteriorate, and causes it 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 of application quantum dot fluorescent material
Method, synthetic quantum dot fluorescence material is modified, one layer of Bipolar Polymer of scion grafting on its surface ligand, improve with
Coat the compatibility between its polymer.Change scheme the disadvantage is that, modified technique is complicated, and is difficult to ensure that glimmering to quantum dot
The uniform cladding of luminescent material, easily causes the reunion of quantum dot fluorescence material, reduces fluorescence quantum efficiency.In consideration of it, being necessary to provide
A kind of quantum dot composite fluorescent material preparation method of process is simple.
The content of the invention
It is an object of the invention to provide for overcoming the water proof oxygen barrier faced in existing quantum dot fluorescent material application to be stranded
The preparation method of the quantum dot composite fluorescent powder of difficult and complex process problem.
The present invention is comprised the following steps:
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) in, 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
Compound may be selected from least one in lead bromide, lead chloride, lead iodide etc.;The halogenation tin compound may be selected from stannic bromide, chlorine
Change at least one in tin, stannic iodide etc.;The methyl ammonium halide may be selected from methyl bromide ammonium, ammonio methacrylate, methylpyridinium iodide
At least one in ammonium etc.;The carbonamidine halogen acid salt may be selected from carbonamidine hydrobromate, carbonamidine hydrogen chlorate, carbonamidine hydriodate
At least one in;The intensive polar solvent can be using dimethylformamide or dimethylacetylamide etc..
2) high molecular polymer is added in solution A, precursor solution is formed after dissolving;
In step 2) in, the high molecular polymer may be selected from polyvinylidene fluoride, bisphenol-A glycerine methacrylate
One kind in ester, polychlorotrifluoroethylene etc.;The addition of the high molecular polymer can be 0.15~0.5g/mL.
3) by step 2) spray drying of the precursor solution that obtains, in spray-drying process, precursor solution is disperseed
Into drop, intensive polar solvent is volatilized out so that drop is changed into spheric granules, stay in high molecular polymer spheric granules from
There is reaction in-situ and form quantum dot in son, and be covered by high molecular polymer spheric granules, obtain final product quantum dot composite fluorescent
Powder.
In step 3) in, the carrier gas of the spraying can be nitrogen or argon gas, and the temperature of spraying can be 30~50 DEG C, spraying
Flow≤150m3/h。
The particle diameter of the quantum dot that the reaction in-situ is formed can be 1~5nm.Obtained quantum dot composite fluorescent powder
Grain diameter can be 0.1~10 μm.
Using technical scheme, have the following 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 base material, without any post processing, you can realized quantum dot fluorescence material bag
It is overlying in water proof oxygen barrier base material, process is simple;The quantum dot composite fluorescent powder of formation, both with water-fast oxygen attack, maintains again
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 and substitute biography
The fluorescent material of system, using simplicity.
Brief description of the drawings
Fig. 1 is coated on the quantum dot distribution situation picture in quantum dot composite fluorescent powder obtained by being observed under transmission electron microscope.
Fig. 2 is coated on the quantum dot pattern picture in quantum dot composite fluorescent powder obtained by being observed under transmission electron microscope.
Specific embodiment
Following examples will the present invention is further illustrated with reference to accompanying drawing.
Embodiment 1
A kind of preparation method of quantum dot composite fluorescent powder, the chemical formula of the quanta point material is CH3NH3PbBr3, institute
The method of stating is comprised the following steps:
(1) the raw material methyl bromide ammonium and lead bromide that will prepare quantum dot are weighed according to molar ratio, are dissolved in highly polar
In solvent, stirring forms homogeneous solution, and material concentration is 0.1mmol/mL;
(2) in a solvent, high molecular polymer is further added, and stirring makes its dissolving form precursor solution, high score
Sub- polymer addition 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, spray
Spray amount 150m3/ h, in spray-drying process, precursor solution is dispersed into drop, intensive polar solvent be volatilized out so that
Drop is changed into spheric granules, and the ion stayed in high molecular polymer spheric granules occurs reaction in-situ and forms quantum dot, and quilt
It is coated in high molecular polymer spheric granules, referring to Fig. 1, so as 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, particle diameter is in 5nm.The gained amount of being coated on is observed referring to Fig. 2, 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 is HC (NH2)2PbI3, system
The raw material carbonamidine hydriodate HC (NH of standby quantum dot2)2I is weighed with lead iodide according to molar ratio, and 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 is CH3NH3SnCl3, system
The raw material ammonio methacrylate of standby quantum dot is weighed with stannic chloride according to molar ratio, and 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 is CH3NH3SnBr(1)
I(2), the described method comprises the following steps:
(1) raw material methyl bromide ammonium, methylpyridinium iodide ammonium, stannic bromide, the stannic iodide of quantum dot will be prepared according to molar ratio
Weigh, be dissolved in intensive polar solvent, stirring forms homogeneous solution, and material concentration is 0.2mmol/mL;
(2) in a solvent, high molecular polymer is further added, and stirring makes its dissolving form precursor solution, high score
Sub- polymer addition is 0.5g/mL;
(3) precursor solution is spray-dried, spraying carrier gas be nitrogen or argon gas, 50 DEG C of vapo(u)rizing temperature,
Mist flow 150m3/h。
The intensive polar solvent is dimethylacetylamide.
The quantum dot that the reaction in-situ is formed, particle diameter 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 is HC (NH2)2PbCl(2)
Br(1), methods described 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 to be 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 stirring makes its dissolving form precursor solution, high score
Sub- polymer addition is 0.3g/mL;
(3) precursor solution is spray-dried, spraying carrier gas be nitrogen or argon gas, 40 DEG C of vapo(u)rizing temperature,
Mist flow 100m3/h。
The intensive polar solvent is dimethylacetylamide.
The quantum dot that the reaction in-situ is formed, particle diameter 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 has perovskite structure, and its chemical formula is HC
(NH2)2SnBr(1.5)I(1.5), methods described 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 stirring makes its dissolving form precursor solution, high score
Sub- polymer addition is 0.4g/mL;
(3) precursor solution is spray-dried, spraying carrier gas be 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.