CN1952038A - Cadmium sulfide bare quantum spot and preparation process - Google Patents
Cadmium sulfide bare quantum spot and preparation process Download PDFInfo
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- CN1952038A CN1952038A CN 200510031067 CN200510031067A CN1952038A CN 1952038 A CN1952038 A CN 1952038A CN 200510031067 CN200510031067 CN 200510031067 CN 200510031067 A CN200510031067 A CN 200510031067A CN 1952038 A CN1952038 A CN 1952038A
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Abstract
The invention disclosed a kind of sulfate cadmium bare quanta spot, which is granulo- nanometer crystal. The fluorescence emission peak lambadamax and peak width at half-height are 415-420nm and 80-100nm respectively. The water-heat synthetic process is also disclosed in the invention: making the water-soluble inorganic cadmium salt (the molar ratio of the cd/s is 1-1.2:1) and the L-aminothiopropionic acid react in the pH 9-13 reaction system. The method is simple, easy to operate and is characterized by low cost. The invention has produced Cds bare quanta spot in different particle diameters (<10 nm). Compared with the present products, the product in this invention has the advantage of high stability, good fluorescence emission peak shape, and narrow peak width at half-height and good monochromaticity. It not only saves time for the surface modification, but also increases its fluorescence efficiency so that it can be used to produce tissue labels after surface modifying.
Description
Technical field
The present invention relates to field of nanometer material technology, particularly a kind of Cadmium Sulfide (CdS) bare quantum spot and preparation method thereof.
Background technology
(quantum dots QDs) can be described as semiconductor nanocrystal (semiconductornanocrystal) again to quantum dot, as a kind of state-of-the art fluorescent material, compares quantum dot with traditional organic dye molecule and has multiple advantage really.Wherein biggest advantage is abundant color.Different types of nano semiconductor material can produce an emission wavelength marker family different, that color is clearly demarcated by dimensional change, and this is that dye molecule can't be realized at all.In addition, its exciting light spectrum width, and continuous distribution, and emmission spectrum monochromaticity is good, and color tunable, and can bear exciting and light emission repeatedly, persistent stability is arranged.Connect again after quantum dot surface is modified and go up biologic specificity material (as Protein A, antibody, Streptavidin etc.), in researchs such as biological chemistry, molecular biology, cytobiology, genomics, proteomics, drug screening, interaction of biomacromolecules, extremely wide application prospect is arranged because its size little (only 20-30nm) can be used as fluorescent probe.Therefore, since nearly more than 20, inorganic materials scholars both domestic and external have carried out extensive and deep research to the inorganic semiconductor nano material.
Usually exist the quantum point grain diameter skewness in the quantum dot preparation at present, bare quantum spot stability is lower, fluorescence emission peak is asymmetric and problem such as peak width at half height broad.Although having taked some countermeasures (as finishing, the organic method of metal etc.) to improve these deficiencies, more international research groups [see: Xiaohu Gao, Yuanyuan Cui, Richard M Levenson, Leland W K Chung ﹠amp; Shuming Nie:In vivo cancer targeting and imaging with semiconductor quantumdots.Nat Biotechnol 2004,22:969-976.], but finishing does not still solve the problem of bare quantum spot poor stability.The organic legal system of comparatively popular in the world metal is equipped with the quantum dot product at present.It is narrow that this legal system is equipped with quantum dot controllable granularity, the fluorescence emission peak of gained, and very outstanding advantage is arranged.But, this method also has unavoidable shortcoming: 1. be to prepare bare quantum spot, one deck organic layer has often been wrapped up on the quantum dot surface that the organic method of metal makes, this has lost the selection of many possibility optimal development for the finishing of follow-up quantum dot as TOPO (trioctyl-phosphine oxide, extremely poison and expensive); 2. not only poisonous, the inflammable but also raw material of the organic method of metal is very expensive, so be subjected to very big restriction in actual applications.
With respect to the quantum dot with organic coating layer, the particle of constituting body phase composite is only contained on the surface of the quantum dot that many inorganic synthetic methods make, and only has cadmium ion or the sulfonium ion that constitutes Cadmium Sulfide as CdS QDs, so be called bare quantum spot again.Wherein water law is that one of modal method [is seen: YaoJian-Xi, Zhao Gao-Ling, Han Gao-Rong:The effect of the ratio of thiourea to Cd
2+On the properties of CdS nanoparticles.Microelectronic Engineering2003,66:115-120.], this perhaps is because the cause that the easy and reaction conditions of method arrives easily.The temperature of reaction of water law generally all is lower than the normal boiling point (promptly about 100 ℃) of the aqueous solution, therefore the structure of water law products obtained therefrom belongs to amorphous substance (nanoparticle) mostly, rather than truly nanocrystalline, cause it under the situation that condition changes, to be very easy to recurring structure and change; Be exactly that the fluorescence emission peak of product is usually sharp-pointed, asymmetric even the impurity acromion occurs on the other hand, the peak width at half height of its fluorescence emission peak is also usually very wide, generally all greater than 120nm[Yao Jian-Xi etc.The effect of the ratioof thiourea to Cd
2+On the properties of CdS nanoparticles.MicroelectronicEngineering 2003 (65): 115-120; Lucia Pedone etc.Synthesis and charaterizationof CdS nanoparticles embedded in a polymethylmethacrylate marix.J.Colloidand Interface Science 2005 (281): 495-500].As the bioluminescence quantum dot that can differentiate, the semiconductor nano of water law preparation has lost actual application value.Report hydrothermal synthesis method (abbreviation hydrothermal method) is arranged in addition, in closed unit (autoclave), employing water is solvent, under the high pressure warming condition, react, prepare 5nm size (peak width at half height of being calculated the XRD diffraction peak by the Scherrer formula obtains), spherical cube of β-CdS of unit cell parameters a=0.5818nm is nanocrystalline (to be seen: 1. Su Yi etc.: nanometer ZnS, synthetic and the sign of CdS hydro-thermal, " applied chemistry ", 1996,13:56), but do not disclose the relevant data or the collection of illustrative plates of the nanocrystalline fluorescent emission character of this CdS, can't learn whether be CdS bare quantum spot with fluorescent emission performance.
Summary of the invention
The technical problem to be solved in the present invention provides a kind of particulate state nanocrystalline structure that has, the Cadmium Sulfide that the fluorescent emission peak shape is good, peak width at half height is narrower (CdS) bare quantum spot.
The particulate state nanocrystalline structure of CdS bare quantum spot of the present invention, its X-ray powder crystal diffraction (XRD) collection of illustrative plates are found two cover crystal parameters: an XRD spectrum for the greenockite of hexagonal structure (Greenockite), another then is that the XRD of the computer cube Cadmium Sulfide of calculating composes (unit cell parameters a=0.58304nm).
The fluorescence emission peak λ max of CdS bare quantum spot of the present invention is generally in the 415-420nm scope, and peak width at half height is generally 80～100nm, preferably is 80nm.
Another technical problem that the present invention will solve provides the preparation method of above-mentioned cadmium sulfide bare quantum spot.Its concrete technical scheme is: adopting hydrothermal synthesis method, is 1～1.2: 1 water-soluble inorganic cadmium salt and L-halfcystine with the Cd/S mol ratio, reacts in the reaction system of pH9～13; Wherein the concentration of water-soluble inorganic cadmium salt in reaction system is 5～54.5mmol/L, and the concentration of L-halfcystine in reaction system is 4.5～50mmol/L.
Preparation method of the present invention provides the dynamic conditions of High Temperature High Pressure for the generation of cadmiumsulfide quantum dot, the relative size of control Cadmium Sulfide crystal nucleation speed and growth velocity and obtain the controlled CdS nanocrystal of size.Find that in research process the factor of regulation and control cadmiumsulfide quantum dot size has: the pH value of raw material type, proportioning raw materials, reactant concn, reaction mixture.The factor that influences product fluorescent emission performance has: the pH value of reaction mixture, nanocrystalline crystal formation, the High Temperature High Pressure residence time.The factor that influences product stability makes the size of product in addition except keeping in Dark Place, because well-known, size is more little, and the specific surface area of product is big more, and stability then descends.
Particularly, the raw material type that the present invention selects for use is: the water-soluble inorganic cadmium salt can be adopted in the cadmium source, and as processable cadmium salts such as cadmium acetate, Cadmium chloride fine powder, cadmium nitrate or Cadmium Sulphates, the quantum dot fluorescence launching effect that wherein adopts cadmium acetate to make is best; And sulfocompounds such as sodium sulphite, Sulfothiorine and compounds containing thiol groups can be adopted in the sulphur source, the preferred L-halfcystine of the present invention, because of using its form that exists that is beneficial to very much the control viscosity of reaction system and sulphur source, and then be convenient to control the quantum dot size that makes.
The present invention most preferably cadmium acetate and L-halfcystine further handles because need not washing etc. as reaction raw materials, and the CdS quantum dot that makes promptly has preferable fluorescent emission performance.
Proportioning raw materials is one of main factor that influences the quantum dot size.Generally speaking, Cd/S (Cd
2+/ S
2-) bigger away from the nanocrystalline size of 1 o'clock CdS semiconduct.This may be that this moment, the viscosity of system was low owing to help forming the nucleus of lesser amt during obviously more than another composition when a kind of composition, and the mass transfer of crystal growth becomes and carries out easily, so obtains large-size crystals.On the contrary, as Cd/S (Cd
2+/ S
2-) near 1 o'clock because the nucleus that generates is many, cause the viscosity of system to increase, the mass transfer difficulty, it is nanocrystalline therefore to obtain small size.
The concentration of reactant in reaction system also is very tangible to the influence of nanocrystalline size.The increase of reactant concn helps the rising of system viscosity, also can make nanocrystalline size decreases, but concentration is too high, surpass 54.5mmol/L as the concentration of water-soluble inorganic cadmium salt in reaction system, the concentration of L-halfcystine in reaction system surpasses 50mmol/L, then the quantum dot reunion is obvious more, and the product that makes also needs further to separate; On the contrary, if concentration is too low, be lower than 5mmol/L as the concentration of water-soluble inorganic cadmium salt in reaction system, the concentration of L-halfcystine in reaction system is lower than 4.5mmol/L, will obtain oarse-grained product (greater than 10nm), and can not get quantum dot.The concentration of the preferred water-soluble inorganic cadmium salt of the present invention in reaction system is 25～54.5mmol/L, and the concentration of L-halfcystine in reaction system is 22.5～50mmol/L.Simultaneously, the present invention is for ease of regulation and control reaction and intuitivism apprehension, and two principal reaction things are taked identical concentration, and are reactant initial concentration separately.Reactant initial concentration that it is generally acknowledged the Hydrothermal Preparation cadmiumsulfide quantum dot should be well below 0.1molL
-1But the inventor found through experiments best reactant initial concentration between 0.01～0.1molL
-1Between, preferably be 0.05～0.1molL
-1
The pH value of reaction mixture also is to realize by the viscosity that changes system to the influence of product granularity basically.PH increases, and viscosity raises, and is unfavorable for mass transfer, helps obtaining a large amount of small crystal nucleus, therefore nanocrystalline size decreases.The pH value of reaction mixture also is influential to the fluorescent emission performance in addition.Suitable pH value generally is controlled between the 10-12, and less than 10 with greater than the 12 fluorescent emission degradation that all can make product, reason may be that the variation of environment makes the structure on quantum dot surface that variation take place, and then has had influence on its fluorescent emission performance.
The hydrothermal synthesis method that the present invention is used is that the pressurization intensification is carried out in autoclave, can be the intensification of single high temperature or two stages.Particularly, pressurization is warming up to lesser temps T
1: 80～110 ℃, t holds time
1: 0～3 hour, again to comparatively high temps T
2: 110～150 ℃, t holds time
2: at least 2 hours; T wherein always holds time
1+ t
2〉=5 hours.Preferably be warming up to 110 ℃-150 ℃.Because the temperature height has Different Effects to crystal nucleation and crystal growth, promptly lower temperature helps nucleation relatively, and higher temperatures then helps crystal and grows up.When system temperature when 80 ℃ are elevated to 150 ℃, the nanocrystalline size that obtains is always in continuous increase, so can obtain the quantum dot of different-grain diameter from small to large.Temperature is not very direct to the quantum dot fluorescence emitting performance, and it is realized by changing product size and then changing its fluorescent emission wavelength; Equally, temperature to the stability of quantum dot also by changing product size and then influence.If the present invention adopts single high temperature (promptly 110～150 ℃), it is 6～8h that preferred high temperature is held time, and the time is too short, and then crystallization is complete inadequately, and the not influence basically of the longer size to quantum dot of high-temperature residence time, fluorescent emission performance and stability increases preparation time on the contrary on foot.And if high temperature is divided into two sections, the prolongation of low-temperature zone time tends to make that the quantum dot size reduces, the fluorescent emission performance strengthens, stability decreases.
One of maximum differential of hydrothermal method of the present invention and existing water law is a temperature of reaction, it generally all will be higher than the boiling point under the aqueous solution standard atmosphere pressure far away, it has prepared＜CdS nanocrystalline (nanocrystal) of the different-grain diameter of 10nm, become quantum dot truly, CdS quantum dot crystallization perfection of the present invention, it is high to have stability, the fluorescent emission peak shape is good, peak width at half height is narrower, advantages such as monochromaticity is good, so preparation method of the present invention has not only overcome the quantum-dot structure instability that water law prepares gained, defectives such as the fluorescence emission peak form is not good enough, the toxicity of also having avoided simultaneously the organic method of metal is with expensive, and simply, easy to operate; And utilize hydrothermal method of the present invention, can prepare the cadmiumsulfide quantum dot of controllable granularity.More valuable is, cadmiumsulfide quantum dot of the present invention has " nude " of the no any parcel of superpower stability and surface, for the later finishing of quantum dot has kept various possibilities; In other words, the present invention has been for the CdS quantum dot that further obtains to can be used as fluorescent material and have a finishing of better fluorescence property provides a large amount of bare quantum spot starting material, can be used for biological tissue's mark after making these CdS bare quantum spots through subsequent disposal such as finishinges.
Description of drawings
Fig. 1 is the XRD figure spectrum of one embodiment of the invention CdS quantum dot (nanocrystalline).
Fig. 2 is the AFM photo (A) and the fluorescent emission spectrogram (B) of embodiment of the invention 1CdS quantum dot.
Fig. 3 is the AFM photo (A) and the fluorescent emission spectrogram (B) of embodiment of the invention 2CdS quantum dot.
Fig. 4 is the AFM photo (A) and the fluorescent emission spectrogram (B) of embodiment of the invention 3CdS quantum dot.
Fig. 5 is the AFM photo (A) and the fluorescent emission spectrogram (B) of embodiment of the invention 4CdS quantum dot.
Fig. 6 is the AFM photo (A) and the fluorescent emission spectrogram (B) of embodiment of the invention 5CdS quantum dot.
Fig. 7 is placed on the fluorescent emission spectrogram after 46 days in the reaction original solution for embodiment 2.
Embodiment
The present invention is further elaborated by following embodiment, but does not limit the scope of the invention.
Embodiment 1
The Cd/S ratio is measured 0.05 (mol/L) cadmium acetate 60ml and 0.05 (mol/L) L-halfcystine 50ml by 1.2 and is mixed in that (concentration of cadmium acetate in reaction system is 27mmol/L in the autoclave inner bag, the reaction density of L-halfcystine is 22.5mmol/L), with concentration is the potential of hydrogen of 1mol/L potassium hydroxide solution regulator solution, and making it pH is 11.Autoclave is airtight, energising heating and pressurizing to 130 ℃, and carry out magnetic agitation.Hot stage insulation 7 hours.Through the naturally cooling cooling
And guarantee to open kettle cover after the autoclave internal pressure drops to normal pressure, material in reactor is transferred in the port grinding bottle, keep in Dark Place.The product characterization data that obtains: atomic force microscope (AFM) photo and fluorescent emission spectrogram are seen shown in Figure 2, and this cadmiumsulfide quantum dot is of a size of about 6.6nm, and λ max is at 417nm, and peak width at half height is 80nm.
Embodiment 2
The Cd/S ratio is measured 0.05 (mol/L) cadmium acetate 60ml and 0.05 (mol/L) L-halfcystine 60ml by 1 and is mixed in that (concentration of cadmium acetate in reaction system is 25mmol/L in the autoclave inner bag, the reaction density of L-halfcystine is 25mmol/L), with concentration is the potential of hydrogen of 1mol/L potassium hydroxide solution regulator solution, and making it pH is 12.Autoclave is airtight, energising heating and pressurizing to 130 ℃, and carry out magnetic agitation.Hot stage insulation 7 hours.The cooling of process naturally cooling is also guaranteed to open kettle cover after the autoclave internal pressure drops to normal pressure, and material in reactor is transferred in the port grinding bottle, keeps in Dark Place.The product characterization data that obtains: atomic force microscope (AFM) photo and fluorescent emission spectrogram are seen shown in Figure 3, and this cadmiumsulfide quantum dot is of a size of 2.0nm, and λ max is at 416nm, and peak width at half height is 80nm.
Embodiment 3
The Cd/S ratio is measured 0.10 (mol/L) cadmium acetate 60ml and 0.10 (mol/L) L-halfcystine 50ml by 1.2 and is mixed in that (concentration of cadmium acetate in reaction system is 54.5mmol/L in the autoclave inner bag, the reaction density of L-halfcystine is 45.4mmol/L), regulating pH with concentration for the 1mol/L potassium hydroxide solution is 12.Autoclave is airtight, energising heating and pressurizing to 130 ℃, and carry out magnetic agitation.Hot stage insulation 6 hours.The cooling of process naturally cooling is also guaranteed to open kettle cover after the autoclave internal pressure drops to normal pressure, and material in reactor is transferred in the port grinding bottle, keeps in Dark Place.The product characterization data that obtains: atomic force microscope (AFM) photo and fluorescent emission spectrogram are seen shown in Figure 4, and this cadmiumsulfide quantum dot is of a size of 4.998nm, 10.469nm, about the twice of the latter for the former, estimate that the latter is a dimer; λ max is at 419nm, and peak width at half height is 83nm; Its X-ray powder crystal diffraction (XRD) collection of illustrative plates is found two cover crystal parameters as shown in Figure 1 among the figure: " ● " then is that the XRD of the computer cube Cadmium Sulfide of calculating composes (unit cell parameters a=0.58304nm) for XRD spectrum, " ■ " of the greenockite of hexagonal structure (Greenockite); In conjunction with the visible product size of atomic force microscope (AFM) photo is about 5nm, has very significantly quantum confined effect, and the fluorescent emission than hard intensity is arranged.
Embodiment 4
The Cd/S ratio is measured 0.05 (mol/L) cadmium acetate 60ml and 0.05 (mol/L) L-halfcystine 50ml by 1.2 and is mixed in that (concentration of cadmium acetate in reaction system is 27mmol/L in the autoclave inner bag, the reaction density of L-halfcystine is 22.5mmol/L), be that 1mol/L potassium hydroxide solution regulator solution pH is 9 with concentration.Autoclave is airtight, and energising is heated to 80 ℃, and carries out magnetic agitation insulation 3 hours.Be warmed up to 110 ℃, hot stage insulation 2 hours.The cooling of process naturally cooling is also guaranteed to open kettle cover after the autoclave internal pressure drops to normal pressure, and material in reactor is transferred in the port grinding bottle, keeps in Dark Place.The product characterization data that obtains: atomic force microscope (AFM) photo and fluorescent emission spectrogram are seen shown in Figure 5, and this cadmiumsulfide quantum dot is of a size of 2.026913nm, 2.457682nm, 24.15842nm, and wherein last is the size of aggregate; λ max is at 416nm, and peak width at half height is 82nm.
Embodiment 5
The Cd/S ratio is measured 0.05 (mol/L) cadmium acetate 60ml and 0.05 (mol/L) L-halfcystine 50ml by 1.2 and is mixed in that (concentration of cadmium acetate in reaction system is 27mmol/L in the autoclave inner bag, the reaction density of L-halfcystine is 22.5mmol/L), be that the pH of 1mol/L potassium hydroxide solution regulator solution is 13 with concentration.Autoclave is airtight, energising heating and pressurizing to 140 ℃, and carry out magnetic agitation.Hot stage insulation 8 hours.The cooling of process naturally cooling is also guaranteed to open kettle cover after the autoclave internal pressure drops to normal pressure, and material in reactor is transferred in the port grinding bottle, keeps in Dark Place.The product characterization data that obtains: atomic force microscope (AFM) photo and fluorescent emission spectrogram are seen shown in Figure 6, and this cadmiumsulfide quantum dot is of a size of 5.582757nm, 11.90723nm, and the latter is the former twice basically, can think that the latter is a dimer; λ max is at 419nm, and peak width at half height is 99nm.
Embodiment 6
The Cd/S ratio is measured 0.01 (mol/L) cadmium acetate 60ml and 0.01 (mol/L) L-halfcystine 50ml by 1.2 and is mixed in that (concentration of cadmium acetate in reaction system is 5.4mmol/L in the autoclave inner bag, the reaction density of L-halfcystine is 4.5mmol/L), be that 1mol/L potassium hydroxide solution regulator solution pH is 9 with concentration.Autoclave is airtight, and energising is heated to 110 ℃, and carries out magnetic agitation insulation 6 hours.The cooling of process naturally cooling is also guaranteed to open kettle cover after the autoclave internal pressure drops to normal pressure, and material in reactor is transferred in the port grinding bottle, keeps in Dark Place.The product characterization data that obtains: atomic force microscope (AFM) photo and fluorescent emission spectrogram show that this cadmiumsulfide quantum dot is of a size of 7.142913nm, 7.204682nm; λ max is at 417nm, and peak width at half height is 83nm.
For ease of regulation and control reaction and intuitivism apprehension, cadmium source, two the principal reaction things in sulphur source are taked identical concentration in the following example, and are reactant initial concentration separately.In fact, what have influence on system viscosity should be concentration in the reaction system, therefore as adopt other reactant initial concentration, as long as its reaction density in reaction system is in the scope of the invention.
Cadmium source in the foregoing description, sulphur source are available from traditional Chinese medicines group.
As seen, the fluorescent emission peak shape of CdS bare quantum spot of the present invention is good, peak width at half height is narrower, illustrate that its particle size distribution is more even, and monochromaticity is good.
The stability test of experimental example 1 CdS bare quantum spot of the present invention:
Select for use embodiment 2 to be sample, be placed on to have preserved in the reaction original solution and carry out the fluorescent emission performance measurement after 46 days again.Collection of illustrative plates as shown in Figure 7, the sharp-pointed and symmetry relatively of the fluorescence emission peak on the fluorescence pattern left side, specific tenacity is big mutually with the frequency multiplication peak on the right.In view of sample size little (2nm), and be placed on reaction and preserved in the original solution and also had hyperfluorescence in 46 days, the cadmiumsulfide quantum dot stability of visible Hydrothermal Preparation of the present invention is high.
Claims (8)
1, a kind of cadmium sulfide bare quantum spot, it is that particulate state is nanocrystalline, and its fluorescence emission peak λ max is 415-420nm, and peak width at half height is 80～100nm.
2, cadmium sulfide bare quantum spot as claimed in claim 1 is characterized in that its peak width at half height is 80nm.
3, the preparation method of cadmium sulfide bare quantum spot as claimed in claim 1 is characterized in that it adopts hydrothermal synthesis method, is 1～1.2: 1 water-soluble inorganic cadmium salt and L-halfcystine with the Cd/S mol ratio, reacts in the reaction system of pH9～13; Wherein the concentration of water-soluble inorganic cadmium salt in reaction system is 5～54.5mmol/L, and the concentration of L-halfcystine in reaction system is 4.5～50mmol/L.
4, preparation method as claimed in claim 3 is characterized in that this water-soluble inorganic cadmium salt is cadmium acetate, Cadmium chloride fine powder, cadmium nitrate or Cadmium Sulphate.
5, preparation method as claimed in claim 3 is characterized in that described hydrothermal synthesis method is that pressurization is warming up to temperature T in autoclave
1: 80～110 ℃, t holds time
1: 0～3 hour, again to temperature T
2: 110～150 ℃, t holds time
2: at least 2 hours; T wherein always holds time
1+ t
2〉=5 hours.
6, preparation method as claimed in claim 5 is characterized in that this temperature T
1Be 80 ℃, t holds time
1It is 3 hours.
7, preparation method as claimed in claim 5 is characterized in that this is always held time is 5～8 hours.
8, preparation method as claimed in claim 3 is characterized in that the concentration of water-soluble inorganic cadmium salt in reaction system is 25～54.5mmol/L, and the concentration of L-halfcystine in reaction system is 22.5～50mmol/L.
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| CN101891241A (en) * | 2010-07-07 | 2010-11-24 | 华侨大学 | Novel method for synthesizing water-soluble blue-fluorescence quantum points |
| CN102241975A (en) * | 2011-05-20 | 2011-11-16 | 河南科技大学 | Quantum dot with core shell structure and preparation method of quantum dot |
| CN101074369B (en) * | 2007-06-27 | 2012-04-18 | 哈尔滨工业大学 | Cds quantum point doped with cobalt inside lattice-ion and its production |
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| CN102660258A (en) * | 2012-04-18 | 2012-09-12 | 中国科学院化学研究所 | Method for preparing water-soluble CdS quantum dot |
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| US6501091B1 (en) * | 1998-04-01 | 2002-12-31 | Massachusetts Institute Of Technology | Quantum dot white and colored light emitting diodes |
| CN1260771C (en) * | 2003-12-02 | 2006-06-21 | 武汉大学 | Method for preparing CdSe quantum point |
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| CN101074369B (en) * | 2007-06-27 | 2012-04-18 | 哈尔滨工业大学 | Cds quantum point doped with cobalt inside lattice-ion and its production |
| CN101891241A (en) * | 2010-07-07 | 2010-11-24 | 华侨大学 | Novel method for synthesizing water-soluble blue-fluorescence quantum points |
| CN102241975A (en) * | 2011-05-20 | 2011-11-16 | 河南科技大学 | Quantum dot with core shell structure and preparation method of quantum dot |
| CN102241975B (en) * | 2011-05-20 | 2013-06-19 | 河南科技大学 | Quantum dot with core shell structure and preparation method of quantum dot |
| CN102634336A (en) * | 2012-04-13 | 2012-08-15 | 南京工业大学 | Light-emitting adjustable ligand-free cadmium sulfide semiconductor quantum dot and preparation method thereof |
| CN102660258A (en) * | 2012-04-18 | 2012-09-12 | 中国科学院化学研究所 | Method for preparing water-soluble CdS quantum dot |
| CN111762809A (en) * | 2020-06-18 | 2020-10-13 | 苏州大学 | Lead-oxygen family compound dimer nanocrystalline, conductive film, preparation method and application |
| CN111762809B (en) * | 2020-06-18 | 2023-11-03 | 苏州大学 | Lead-oxygen compound dimer nanocrystalline, conductive film, preparation method and application |
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