CN102766463B - Preparation method of water-soluble CdSe quantum dots - Google Patents
Preparation method of water-soluble CdSe quantum dots Download PDFInfo
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- CN102766463B CN102766463B CN201210275877.2A CN201210275877A CN102766463B CN 102766463 B CN102766463 B CN 102766463B CN 201210275877 A CN201210275877 A CN 201210275877A CN 102766463 B CN102766463 B CN 102766463B
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Abstract
The invention discloses a preparation method of water-soluble CdSe quantum dots and belongs to the field of nanotechnology preparation. According to the method, sodium selenite is used as a selenium source, cadmium chloride is used as a cadmium source, mercaptopropionic acid and sodium hexametaphosphate are used as double complexing agents, and hydrazine hydrate deoxidizes the sodium selenite in an aqueous solution to prepare the water-soluble CdSe quantum dots in a one-step mode. The preparation method of the water-soluble CdSe quantum dots is simple and easy to operate, mild in conditions and suitable for batch preparation and large-scale synthesis. The prepared CdSe quantum dots are strong in fluorescent radiation in green light areas, and the radiation intensity can be controlled by controlling reaction time.
Description
Technical field
That the present invention relates to is a kind of preparation method of field of nanometer technology, particularly a kind of preparation method of water-soluble CdSe quantum dot.
Background technology
Quantum dot (Quantum dot is called for short QD) is the semiconductor nano crystal grain that a kind of radius was less than or approached Bohr's exciton radius.Quantum dot has the absorb light spectrum width, and emmission spectrum is narrow and symmetrical, and glow color is adjustable, and fluorescence intensity and light stability high, be applied widely in fields such as biomarker, bio-sensing and field of biological detection.The quantum dot of biologically applying at present is mostly from organic synthesis, the synthetic quantum point grain diameter of the method is evenly distributed, quantum yield is high, but preparation condition is harsh, cost is high, toxicity is large, and prepared quantum dot is insoluble in water, need the further derivative water-based quantum dot that turns to obtain application at life science.The CdSe quantum dot is a kind of important II-VI family quantum dot, although in aqueous phase system, preparation CdSe quantum dot has better water-soluble and biocompatibility, but prepared quantum dot quantum yield is lower, and prepare unsettled Selenium hydride (H due to needs under oxygen-free environment
2se) or sodium hydrogen selenide (NaHSe) as selenium source, the preparation process proceed step by step, scale is synthetic and cost suitability for industrialized production is higher.
Through the literature search to prior art, find, Oluwafemi etc. have delivered the paper that is entitled as " A novel one-pot route for the synthesis of water-soluble cadmium selenide nanoparticles " (" step prepares the water-soluble CdSe quantum dot ") on " Journal of Crystal Growth " (the 310th volume 3230-3234 page in 2008), utilization stable selenium powder under state of nature, as selenium source, adopts method step in water of sodium borohydride reduction selenium powder to prepare the water-soluble CdSe quantum dot.Method one step that the method utilization generates NaHSe online prepares the water-soluble CdSe quantum dot, but prepared quantum dot fluorescence yield of radiation a little less than, and preparation process still needs oxygen-free environment, the synthetic cost of scale is higher.
Chinese patent CN1978587A(application number: 200510019940.6) disclose a kind of method that ultrasonic water bath adds hot preparation water-soluble CdSe quantum dot; the method needs high pure nitrogen deoxygenation and protection; and the introducing of ultrasonic technique is not only with new sound pollution and energy consumption; and make preparation facilities complicated, be difficult to realize that scale is synthetic.
Summary of the invention
For deficiency of the prior art, the invention provides a kind of preparation method of water-soluble CdSe quantum dot.Utilize hydrazine hydrate to reduce Sodium Selenite as reductive agent, adopt bistable agent technology one step based on thiohydracrylic acid and Sodium hexametaphosphate 99 to prepare fluorescence property water-soluble CdSe quantum dot preferably.
At first the present invention selects Cadmium chloride fine powder to originate as cadmium ion, the online plasma selenium produced of hydrazine hydrate reduction Sodium Selenite is as selenium source, under the prerequisite of double complexing agents thiohydracrylic acid and Sodium hexametaphosphate 99 existence, by the mode of controlling return time, obtain and can produce green fluorescence and the adjustable water-soluble CdSe quantum dot of fluorescence intensity.
A kind of preparation method of water-soluble CdSe quantum dot, step is as follows:
(1) add successively Sodium hexametaphosphate 99 and thiohydracrylic acid in the cadmium chloride solution that is 1.0-5.0 mM/l to concentration under room temperature, the mol ratio of Cadmium chloride fine powder and Sodium hexametaphosphate 99 is 1:(0.7-4), the mol ratio of Cadmium chloride fine powder and thiohydracrylic acid is 1:(1-4), adition process is carried out under magnetic agitation, after thiohydracrylic acid adds end, solution acidity is adjusted to pH=7-9, obtains the precursor solution of cadmium;
(2) under the magnetic agitation condition, add Sodium Selenite in the precursor solution of the cadmium made to step (1), the mol ratio of Cadmium chloride fine powder and Sodium Selenite is 1:(0.02-0.15);
(3) add hydrazine hydrate in the solution of step (2) gained, thermostatically heating backflow 5-13 hour under 100 ℃ of conditions, obtain the quantum dot solution of different fluorescent emission wavelength; Cadmium chloride fine powder and hydrazine hydrate mol ratio are 1:(200-400);
(4) step (3) gained water-soluble CdSe quantum dot solution is centrifugal with the rotating speed of 7500 ~ 8000 rev/mins, after removing supernatant liquid, the gained precipitation is dispersed in acetone, centrifugation three times, finally will be precipitated and dissolved in water, obtain the water-soluble CdSe quantum dot.
Preferably, in above-mentioned steps (1), the mol ratio of Cadmium chloride fine powder and Sodium hexametaphosphate 99 is 1:(0.7-2.1), further preferred 1:2.1, the mol ratio of Cadmium chloride fine powder and thiohydracrylic acid is 1:(1-3), further preferred 1:2.5.
In above-mentioned steps (2), the mol ratio of Cadmium chloride fine powder and Sodium Selenite is 1:(0.02-0.10), further preferred 1:0.05.
In above-mentioned steps (3), the mol ratio of Cadmium chloride fine powder and hydrazine hydrate is 1:260.
The time that in above-mentioned steps (3), thermostatically heating refluxes is 5 hours to 10 hours.
The fluorescence spectrum figure of CdSe quantum dot prepared by the present invention is obtained by the collection of WGY-10 type spectrophotofluorometer, and uv-visible absorption spectroscopy is obtained by the collection of TU-1901 series ultraviolet visible spectrophotometer.
CdSe quantum dot fluorescence emission peak prepared by the present invention concentrates on the 490-530nm left and right, is macroscopic high strength green fluorescence, and its luminous intensity can be by the method regulation and control in reaction times.The quantum dot fluorescence emission good water solubility that the present invention is prepared, stability is strong, is applicable to doing the application in the Quantum Dot Labeling field.Working method of the present invention is convenient, and reaction conditions is environmentally friendly, and gentle, controlled, and the scale that is adapted at laboratory is synthesized and industrial production.
The accompanying drawing explanation
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Fig. 1 is water-soluble CdSe quantum dot made in embodiment 1.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Fig. 2 is water-soluble CdSe quantum dot made in embodiment 2.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Fig. 3 is water-soluble CdSe quantum dot made in embodiment 3.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Fig. 4 is water-soluble CdSe quantum dot made in embodiment 4.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Fig. 5 is water-soluble CdSe quantum dot made in embodiment 5.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Fig. 6 is water-soluble CdSe quantum dot made in embodiment 6.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Fig. 7 is water-soluble CdSe quantum dot made in embodiment 7.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Fig. 8 is water-soluble CdSe quantum dot made in embodiment 8.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Fig. 9 is water-soluble CdSe quantum dot made in embodiment 9.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 10 is water-soluble CdSe quantum dot made in embodiment 10.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 11 is water-soluble CdSe quantum dot made in embodiment 11.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 12 is water-soluble CdSe quantum dot made in embodiment 12.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 13 is water-soluble CdSe quantum dot made in embodiment 13.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 14 is water-soluble CdSe quantum dot made in embodiment 14.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 15 is water-soluble CdSe quantum dot made in embodiment 15.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 16 is water-soluble CdSe quantum dot made in embodiment 16.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 17 is water-soluble CdSe quantum dot made in embodiment 17.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 18 is water-soluble CdSe quantum dot made in embodiment 18.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 19 is water-soluble CdSe quantum dot made in embodiment 19.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 20 is water-soluble CdSe quantum dot made in embodiment 20.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 21 is water-soluble CdSe quantum dot made in embodiment 21.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 22 is water-soluble CdSe quantum dot made in embodiment 22.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 23 is water-soluble CdSe quantum dot made in embodiment 23.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 24 is water-soluble CdSe quantum dot made in embodiment 24.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 25 is water-soluble CdSe quantum dot made in embodiment 25.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 26 is water-soluble CdSe quantum dot made in embodiment 26.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 27 is water-soluble CdSe quantum dot made in embodiment 27.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 28 is water-soluble CdSe quantum dot made in embodiment 28.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 29 is water-soluble CdSe quantum dot made in embodiment 29.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 30 is water-soluble CdSe quantum dot made in embodiment 30.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 31 is water-soluble CdSe quantum dot made in embodiment 31.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 32 is water-soluble CdSe quantum dot made in embodiment 32.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 33 is water-soluble CdSe quantum dot made in embodiment 33.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 34 is water-soluble CdSe quantum dot made in embodiment 34.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 35 is water-soluble CdSe quantum dot made in embodiment 35.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 36 is water-soluble CdSe quantum dot made in embodiment 36.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 37 is water-soluble CdSe quantum dot made in embodiment 37.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 38 is water-soluble CdSe quantum dot made in embodiment 38.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 39 is water-soluble CdSe quantum dot made in embodiment 39.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 40 is water-soluble CdSe quantum dot made in embodiment 40.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 41 is water-soluble CdSe quantum dot made in embodiment 41.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 42 is water-soluble CdSe quantum dot made in embodiment 42.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 43 is water-soluble CdSe quantum dot made in embodiment 43.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 44 is water-soluble CdSe quantum dot made in embodiment 44.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 45 is water-soluble CdSe quantum dot made in embodiment 45.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 46 is water-soluble CdSe quantum dot made in embodiment 46.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 47 is water-soluble CdSe quantum dot made in embodiment 47.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 48 is water-soluble CdSe quantum dot made in embodiment 48.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 49 is water-soluble CdSe quantum dot made in embodiment 49.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 50 is water-soluble CdSe quantum dot made in embodiment 50.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 51 is water-soluble CdSe quantum dot made in embodiment 51.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 52 is water-soluble CdSe quantum dot made in embodiment 52.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 53 is water-soluble CdSe quantum dot made in embodiment 53.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 54 is water-soluble CdSe quantum dot made in embodiment 54.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 55 is water-soluble CdSe quantum dot made in embodiment 55.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 56 is water-soluble CdSe quantum dot made in embodiment 56.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 57 is water-soluble CdSe quantum dot made in embodiment 57.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 58 is water-soluble CdSe quantum dot made in embodiment 58.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 59 is water-soluble CdSe quantum dot made in embodiment 59.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 60 is water-soluble CdSe quantum dot made in embodiment 60.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 61 is water-soluble CdSe quantum dot made in embodiment 61.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 62 is water-soluble CdSe quantum dot made in embodiment 62.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 63 is water-soluble CdSe quantum dot made in embodiment 63.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 64 is water-soluble CdSe quantum dot made in embodiment 64.
Fluorescence spectrum figure and uv-visible absorption spectroscopy figure that Figure 65 is water-soluble CdSe quantum dot made in embodiment 65.
Embodiment
Below in conjunction with embodiment, the present invention will be further described, and the present embodiment is implemented take technical solution of the present invention under prerequisite, provided detailed embodiment and process, but protection scope of the present invention is not limited to this.
The embodiment of the present invention is raw materials used is commercial product, and wherein, Sodium Selenite is Sodium selenite (Na2SeO3) pentahydrate, and the purity of Sodium hexametaphosphate 99 used is 70%.
A kind of preparation method of water-soluble CdSe quantum dot, step is as follows:
(1) measure 50 milliliters of the cadmium chloride solutions of 3.2 mM/ls under room temperature; Add successively 293.6mg Sodium hexametaphosphate 99 and 34.6 microlitre thiohydracrylic acids under the magnetic agitation condition, after thiohydracrylic acid adds end, with 1 mol/L sodium hydroxide solution, pH is adjusted to 8, obtain the precursor solution of cadmium;
(2), under the magnetic agitation condition, in the precursor solution of the cadmium made to step (1), add the 2.2mg Sodium selenite (Na2SeO3) pentahydrate;
(3) add the hydrazine hydrate solution of 2.4 milliliter 85% in the solution obtained to step (2), at 100 ℃ of lower thermostatically heating 5h, obtain the water-soluble CdSe quantum dot solution;
(4) step (3) gained water-soluble CdSe quantum dot solution is centrifugal with the rotating speed of 8000 rev/mins, after the removal supernatant liquid, the gained precipitation is dispersed in acetone, centrifugation three times, finally will be precipitated and dissolved in water, obtain the water-soluble CdSe quantum dot.
As shown in Figure 1, gained water-soluble CdSe quantum dot maximum emission wavelength is 507.2nm, and peak width at half height is 39.2nm.
Embodiment 2
Step is with embodiment 1, and difference is thermostatically heating backflow 7h in step (3).
As shown in Figure 2, gained water-soluble CdSe quantum dot maximum emission wavelength is 512.8nm, and peak width at half height is 38.8nm.
Embodiment 3
Step is with embodiment 1, and difference is that in step (3), thermostatically heating refluxes 9 hours.
As shown in Figure 3, gained water-soluble CdSe quantum dot maximum emission wavelength is 517.4nm, and peak width at half height is 39.6nm.
Embodiment 4
Step is with embodiment 1, and difference is that in step (3), thermostatically heating refluxes 11 hours.
As shown in Figure 4, gained water-soluble CdSe quantum dot maximum emission wavelength is 521.6nm, and peak width at half height is 40.4nm.
Embodiment 5
Step is with embodiment 1, and difference is that in step (3), thermostatically heating refluxes 13 hours.
As shown in Figure 5, gained water-soluble CdSe quantum dot maximum emission wavelength is 525.0nm, and peak width at half height is 40.0nm.
Embodiment 6
Step is with embodiment 1, and difference is with 1 mol/L sodium hydroxide solution, pH to be adjusted to 7 in step (1).
As shown in Figure 6, gained water-soluble CdSe quantum dot maximum emission wavelength is 501.8nm, and peak width at half height is 38.2nm.
Embodiment 7
Step is with embodiment 2, and difference is with 1 mol/L sodium hydroxide solution, pH to be adjusted to 7 in step (1).
As shown in Figure 7, gained water-soluble CdSe quantum dot maximum emission wavelength is 508.0nm, and peak width at half height is 36.6nm.
Embodiment 8
Step is with embodiment 3, and difference is with 1 mol/L sodium hydroxide solution, pH to be adjusted to 7 in step (1).
As shown in Figure 8, gained water-soluble CdSe quantum dot maximum emission wavelength is 511.4nm, and peak width at half height is 36.8nm.
Embodiment 9
Step is with embodiment 4, and difference is with 1 mol/L sodium hydroxide solution, pH to be adjusted to 7 in step (1).
As shown in Figure 9, gained water-soluble CdSe quantum dot maximum emission wavelength is 515.6nm, and peak width at half height is 36.6nm.
Embodiment 10
Step is with embodiment 5, and difference is with 1 mol/L sodium hydroxide solution, pH to be adjusted to 7 in step (1).
As shown in figure 10, gained water-soluble CdSe quantum dot maximum emission wavelength is 519.2nm, and peak width at half height is 37.2nm.
Embodiment 11
Step is with embodiment 1, and difference is with 1 mol/L sodium hydroxide solution, pH to be adjusted to 9 in step (1).
As shown in figure 11, gained water-soluble CdSe quantum dot maximum emission wavelength is 504.0nm, and peak width at half height is 38.6nm.
Embodiment 12
Step is with embodiment 2, and difference is with 1 mol/L sodium hydroxide solution, pH to be adjusted to 9 in step (1).
As shown in figure 12, gained water-soluble CdSe quantum dot maximum emission wavelength is 508.0nm, and peak width at half height is 37.2nm.
Embodiment 13
Step is with embodiment 3, and difference is with 1 mol/L sodium hydroxide solution, pH to be adjusted to 9 in step (1).
As shown in figure 13, gained water-soluble CdSe quantum dot maximum emission wavelength is 513.6nm, and peak width at half height is 37.2nm.
Embodiment 14
Step is with embodiment 4, and difference is with 1 mol/L sodium hydroxide solution, pH to be adjusted to 9 in step (1).
As shown in figure 14, gained water-soluble CdSe quantum dot maximum emission wavelength is 519.0nm, and peak width at half height is 38.0nm.
Embodiment 15
Step is with embodiment 5, and difference is with 1 mol/L sodium hydroxide solution, pH to be adjusted to 9 in step (1).
As shown in figure 15, gained water-soluble CdSe quantum dot maximum emission wavelength is 523.0nm, and peak width at half height is 38.2nm.
Embodiment 16
Step is with embodiment 1, and difference is that in step (1), the consumption of Sodium hexametaphosphate 99 is 559.2mg.
As shown in figure 16, gained water-soluble CdSe quantum dot maximum emission wavelength is 494.2nm, and peak width at half height is 40.0nm.
Embodiment 17
Step is with embodiment 2, and difference is that in step (1), the consumption of Sodium hexametaphosphate 99 is 559.2mg.
As shown in figure 17, gained water-soluble CdSe quantum dot maximum emission wavelength is 500.4nm, and peak width at half height is 38.2nm.
Embodiment 18
Step is with embodiment 3, and difference is that in step (1), the consumption of Sodium hexametaphosphate 99 is 559.2mg.
As shown in figure 18, gained water-soluble CdSe quantum dot maximum emission wavelength is 505.4nm, and peak width at half height is 37.8nm.
Embodiment 19
Step is with embodiment 4, and difference is that in step (1), the consumption of Sodium hexametaphosphate 99 is 559.2mg.
As shown in figure 19, gained water-soluble CdSe quantum dot maximum emission wavelength is 508.4nm, and peak width at half height is 36.8nm.
Embodiment 20
Step is with embodiment 5, and difference is that in step (1), the consumption of Sodium hexametaphosphate 99 is 559.2mg.
As shown in figure 20, gained water-soluble CdSe quantum dot maximum emission wavelength is 512.4nm, and peak width at half height is 36.6nm.
Embodiment 21
Step is with embodiment 1, and difference is that in step (1), the consumption of Sodium hexametaphosphate 99 is 97.9mg.
As shown in figure 21, gained water-soluble CdSe quantum dot maximum emission wavelength is 506.6nm, and peak width at half height is 38.2nm.
Embodiment 22
Step is with embodiment 2, and difference is that in step (1), the consumption of Sodium hexametaphosphate 99 is 97.9mg.
As shown in figure 22, the water-soluble CdSe quantum dot maximum emission wavelength that obtains is 515.0nm, and peak width at half height is 38.0nm.
Embodiment 23
Step is with embodiment 3, and difference is that in step (1), the consumption of Sodium hexametaphosphate 99 is 97.9mg.
As shown in figure 23, gained water-soluble CdSe quantum dot maximum emission wavelength is 521.8nm, and peak width at half height is 38.8nm.
Embodiment 24
Step is with embodiment 4, and difference is that in step (1), the consumption of Sodium hexametaphosphate 99 is 97.9mg.
As shown in figure 24, gained water-soluble CdSe quantum dot maximum emission wavelength is 527.2nm, and peak width at half height is 39.0nm.
Embodiment 25
Step is with embodiment 5, and difference is that in step (1), the consumption of Sodium hexametaphosphate 99 is 97.9mg.
As shown in figure 25, gained water-soluble CdSe quantum dot maximum emission wavelength is 533.0nm, and peak width at half height is 38.8nm.
Embodiment 26
Step is with embodiment 1, and difference is that in step (1), the consumption of thiohydracrylic acid is 55.4 μ L.
As shown in figure 26, gained water-soluble CdSe quantum dot maximum emission wavelength is 494.8nm, and peak width at half height is 39.8nm.
Embodiment 27
Step is with embodiment 2, and difference is that in step (1), the consumption of thiohydracrylic acid is 55.4 μ L.
As shown in figure 26, gained water-soluble CdSe quantum dot maximum emission wavelength is 501.2nm, and peak width at half height is 37.2nm.
Embodiment 28
Step is with embodiment 3, and difference is that in step (1), the consumption of thiohydracrylic acid is 55.4 μ L.
As shown in figure 28, gained water-soluble CdSe quantum dot maximum emission wavelength is 506.8nm, and peak width at half height is 36.0nm.
Embodiment 29
Step is with embodiment 4, and difference is that in step (1), the consumption of thiohydracrylic acid is 55.4 μ L.
As shown in figure 29, gained water-soluble CdSe quantum dot maximum emission wavelength is 512.0nm, and peak width at half height is 35.6nm.
Embodiment 30
Step is with embodiment 5, and difference is that in step (1), the consumption of thiohydracrylic acid is 55.4 μ L.
As shown in figure 30, gained water-soluble CdSe quantum dot maximum emission wavelength is 514.8nm, and peak width at half height is 35.4nm.
Embodiment 31
Step is with embodiment 1, and difference is that in step (1), the consumption of thiohydracrylic acid is 13.8 μ L.
As shown in figure 31, gained water-soluble CdSe quantum dot maximum emission wavelength is 506.8nm, and peak width at half height is 36.2nm.
Embodiment 32
Step is with embodiment 2, and difference is that in step (1), the consumption of thiohydracrylic acid is 13.8 μ L.
Shown in figure 32, gained water-soluble CdSe quantum dot maximum emission wavelength is 512.2nm, and peak width at half height is 36.6nm.
Embodiment 33
Step is with embodiment 3, and difference is that in step (1), the consumption of thiohydracrylic acid is 13.8 μ L.
As shown in figure 33, gained water-soluble CdSe quantum dot maximum emission wavelength is 516.4nm, and peak width at half height is 37.8nm.
Embodiment 34
Step is with embodiment 4, and difference is that in step (1), the consumption of thiohydracrylic acid is 13.8 μ L.
As shown in figure 34, gained water-soluble CdSe quantum dot maximum emission wavelength is 519.8nm, and peak width at half height is 39.0nm.
Embodiment 35
Step is with embodiment 5, and difference is that in step (1), the consumption of thiohydracrylic acid is 13.8 μ L.
As shown in figure 35, gained water-soluble CdSe quantum dot maximum emission wavelength is 524.4nm, and peak width at half height is 39.4nm.
Embodiment 36
Step is with embodiment 1, and difference is to add the 0.9mg Sodium selenite (Na2SeO3) pentahydrate in step (2).
As shown in figure 36, gained water-soluble CdSe quantum dot maximum emission wavelength is 496.0nm, and peak width at half height is 36.0nm.
Embodiment 37
Step is with embodiment 2, and difference is to add the 0.9mg Sodium selenite (Na2SeO3) pentahydrate in step (2).
As shown in figure 37, gained water-soluble CdSe quantum dot maximum emission wavelength is 503.8nm, and peak width at half height is 34.8nm.
Embodiment 38
Step is with embodiment 3, and difference is to add the 0.9mg Sodium selenite (Na2SeO3) pentahydrate in step (2).
As shown in figure 38, gained water-soluble CdSe quantum dot maximum emission wavelength is 509.8nm, and peak width at half height is 33.6nm.
Embodiment 39
Step is with embodiment 4, and difference is to add the 0.9mg Sodium selenite (Na2SeO3) pentahydrate in step (2).
As shown in figure 39, gained water-soluble CdSe quantum dot maximum emission wavelength is 514.4nm, and peak width at half height is 33.4nm.
Embodiment 40
Step is with embodiment 5, and difference is to add the 0.9mg Sodium selenite (Na2SeO3) pentahydrate in step (2).
As shown in figure 40, gained water-soluble CdSe quantum dot maximum emission wavelength is 517.8nm, and peak width at half height is 33.4nm.
Embodiment 41
Step is with embodiment 1, and difference is to add the 6.5mg Sodium selenite (Na2SeO3) pentahydrate in step (2).
As shown in figure 41, gained water-soluble CdSe quantum dot maximum emission wavelength is 514.0nm, and peak width at half height is 38.8nm.
Embodiment 42
Step is with embodiment 2, and difference is to add the 6.5mg Sodium selenite (Na2SeO3) pentahydrate in step (2).
As shown in figure 42, gained water-soluble CdSe quantum dot maximum emission wavelength is 517.0nm, and peak width at half height is 40.6nm.
Embodiment 43
Step is with embodiment 3, and difference is to add the 6.5mg Sodium selenite (Na2SeO3) pentahydrate in step (2).
As shown in figure 43, gained water-soluble CdSe quantum dot maximum emission wavelength is 521.8nm, and peak width at half height is 42.4nm.
Embodiment 44
Step is with embodiment 4, and difference is to add the 6.5mg Sodium selenite (Na2SeO3) pentahydrate in step (2).
As shown in figure 44, gained water-soluble CdSe quantum dot maximum emission wavelength is 526.0nm, and peak width at half height is 42.6nm.
Embodiment 45
Step is with embodiment 5, and difference is to add the 6.5mg Sodium selenite (Na2SeO3) pentahydrate in step (2).
As shown in figure 45, gained water-soluble CdSe quantum dot maximum emission wavelength is 530.4nm, and peak width at half height is 44.0nm.
Embodiment 46
Step is with embodiment 1, and difference is to add 3.69 milliliters of hydrazine hydrates in step (3).
As shown in figure 46, gained water-soluble CdSe quantum dot maximum emission wavelength is 509.4nm, and peak width at half height is 36.9nm.
Embodiment 47
Step is with embodiment 2, and difference is to add 3.69 milliliters of hydrazine hydrates in step (3).
As shown in figure 47, gained water-soluble CdSe quantum dot maximum emission wavelength is 515.4nm, and peak width at half height is 37.5nm.
Embodiment 48
Step is with embodiment 3, and difference is to add 3.69 milliliters of hydrazine hydrates in step (3).
As shown in figure 48, gained water-soluble CdSe quantum dot maximum emission wavelength is 519.8nm, and peak width at half height is 38.1nm.
Embodiment 49
Step is with embodiment 4, and difference is to add 3.69 milliliters of hydrazine hydrates in step (3).
As shown in figure 49, gained water-soluble CdSe quantum dot maximum emission wavelength is 525.6nm, and peak width at half height is 38.0nm.
Step is with embodiment 5, and difference is to add 3.69 milliliters of hydrazine hydrates in step (3).
As shown in figure 50, gained water-soluble CdSe quantum dot maximum emission wavelength is 531.2nm, and peak width at half height is 37.9nm.
Embodiment 51
Step is with embodiment 1, and difference is to add 1.85 milliliters of hydrazine hydrates in step (3).
As shown in Figure 51, gained water-soluble CdSe quantum dot maximum emission wavelength is 494.2nm, and peak width at half height is 38.6nm.
Embodiment 52
Step is with embodiment 2, and difference is to add 1.85 milliliters of hydrazine hydrates in step (3).
As shown in Figure 52, the water-soluble CdSe quantum dot maximum emission wavelength that obtains is 500.0nm, and peak width at half height is 36.9nm.
Embodiment 53
Step is with embodiment 3, and difference is to add 1.85 milliliters of hydrazine hydrates in step (3).
As shown in Figure 3, gained water-soluble CdSe quantum dot maximum emission wavelength is 504.2nm, and peak width at half height is 35.5nm.
Embodiment 54
Step is with embodiment 4, and difference is to add 1.85 milliliters of hydrazine hydrates in step (3).
As shown in Figure 54, gained water-soluble CdSe quantum dot maximum emission wavelength is 508.2nm, and peak width at half height is 35.1nm.
Embodiment 55
Step is with embodiment 5, and difference is to add 1.85 milliliters of hydrazine hydrates in step (3).
As shown in Figure 55, gained water-soluble CdSe quantum dot maximum emission wavelength is 510.2nm, and peak width at half height is 34.8nm.
Embodiment 56
Step is with embodiment 1, and difference is: step is selected the cadmium chloride solution of 1.0 mM/ls in (1); Add successively 91.8mg Sodium hexametaphosphate 99 and 10.8 microlitre thiohydracrylic acids under the magnetic agitation condition; In step (2), add the 0.7mg Sodium selenite (Na2SeO3) pentahydrate; In step (3), add the hydrazine hydrate solution of 0.75 milliliter 85%;
As shown in Figure 56, gained water-soluble CdSe quantum dot maximum emission wavelength is 490.0nm, and peak width at half height is 37.7nm.
Embodiment 57
Step is with embodiment 2, and difference is: step is selected the cadmium chloride solution of 1.0 mM/ls in (1); Add successively 91.8mg Sodium hexametaphosphate 99 and 10.8 microlitre thiohydracrylic acids under the magnetic agitation condition; In step (2), add the 0.7mg Sodium selenite (Na2SeO3) pentahydrate; In step (3), add the hydrazine hydrate solution of 0.75 milliliter 85%;
As shown in Figure 57, gained water-soluble CdSe quantum dot maximum emission wavelength is 495.0nm, and peak width at half height is 36.9nm.
Embodiment 58
Step is with embodiment 3, and difference is: step is selected the cadmium chloride solution of 1.0 mM/ls in (1); Add successively 91.8mg Sodium hexametaphosphate 99 and 10.8 microlitre thiohydracrylic acids under the magnetic agitation condition; In step (2), add the 0.7mg Sodium selenite (Na2SeO3) pentahydrate; In step (3), add the hydrazine hydrate solution of 0.75 milliliter 85%;
As shown in Figure 58, gained water-soluble CdSe quantum dot maximum emission wavelength is 500.0nm, and peak width at half height is 36.0nm.
Embodiment 59
Step is with embodiment 4, and difference is: step is selected the cadmium chloride solution of 1.0 mM/ls in (1); Add successively 91.8mg Sodium hexametaphosphate 99 and 10.8 microlitre thiohydracrylic acids under the magnetic agitation condition; In step (2), add the 0.7mg Sodium selenite (Na2SeO3) pentahydrate; In step (3), add the hydrazine hydrate solution of 0.75 milliliter 85%;
As shown in Figure 59, gained water-soluble CdSe quantum dot maximum emission wavelength is 505.2nm, and peak width at half height is 35.4nm.
Embodiment 60
Step is with embodiment 5, and difference is: step is selected the cadmium chloride solution of 1.0 mM/ls in (1); Add successively 91.8mg Sodium hexametaphosphate 99 and 10.8 microlitre thiohydracrylic acids under the magnetic agitation condition; In step (2), add the 0.7mg Sodium selenite (Na2SeO3) pentahydrate; In step (3), add the hydrazine hydrate solution of 0.75 milliliter 85%;
As shown in Figure 60, gained water-soluble CdSe quantum dot maximum emission wavelength is 509.6nm, and peak width at half height is 35.2nm.
Embodiment 61
Step is with embodiment 1, and difference is: step is selected the cadmium chloride solution of 5.0 mM/ls in (1); Add successively 458.8mg Sodium hexametaphosphate 99 and 10.8 microlitre thiohydracrylic acids under the magnetic agitation condition; In step (2), add the 13.8mg Sodium selenite (Na2SeO3) pentahydrate; In step (3), add the hydrazine hydrate solution of 3.75 milliliter 85%;
As shown in Figure 61, gained water-soluble CdSe quantum dot maximum emission wavelength is 504.0nm, and peak width at half height is 37.4nm.
Embodiment 62
Step is with embodiment 2, and difference is: step is selected the cadmium chloride solution of 5.0 mM/ls in (1); Add successively 458.8mg Sodium hexametaphosphate 99 and 10.8 microlitre thiohydracrylic acids under the magnetic agitation condition; In step (2), add the 13.8mg Sodium selenite (Na2SeO3) pentahydrate; In step (3), add the hydrazine hydrate solution of 3.75 milliliter 85%;
As shown in Figure 62, gained water-soluble CdSe quantum dot maximum emission wavelength is 509.8nm, and peak width at half height is 37.1nm.
Embodiment 63
Step is with embodiment 3, and difference is: step is selected the cadmium chloride solution of 5.0 mM/ls in (1); Add successively 458.8mg Sodium hexametaphosphate 99 and 10.8 microlitre thiohydracrylic acids under the magnetic agitation condition; In step (2), add the 13.8mg Sodium selenite (Na2SeO3) pentahydrate; In step (3), add the hydrazine hydrate solution of 3.75 milliliter 85%;
As shown in Figure 63, gained water-soluble CdSe quantum dot maximum emission wavelength is 514.0nm, and peak width at half height is 37.0nm.
Embodiment 64
Step is with embodiment 4, and difference is: step is selected the cadmium chloride solution of 5.0 mM/ls in (1); Add successively 458.8mg Sodium hexametaphosphate 99 and 10.8 microlitre thiohydracrylic acids under the magnetic agitation condition; In step (2), add the 13.8mg Sodium selenite (Na2SeO3) pentahydrate; In step (3), add the hydrazine hydrate solution of 3.75 milliliter 85%;
As shown in Figure 64, gained water-soluble CdSe quantum dot maximum emission wavelength is 518.8nm, and peak width at half height is 37.4nm.
Embodiment 65
Step is with embodiment 5, and difference is: step is selected the cadmium chloride solution of 5.0 mM/ls in (1); Add successively 458.8mg Sodium hexametaphosphate 99 and 10.8 microlitre thiohydracrylic acids under the magnetic agitation condition; In step (2), add the 13.8mg Sodium selenite (Na2SeO3) pentahydrate; In step (3), add the hydrazine hydrate solution of 3.75 milliliter 85%;
As shown in Figure 65, gained water-soluble CdSe quantum dot maximum emission wavelength is 522.6nm, and peak width at half height is 37.6nm.
Claims (7)
1. the preparation method of a water-soluble CdSe quantum dot, it is characterized in that, select Cadmium chloride fine powder as the cadmium source, Sodium selenite (Na2SeO3) pentahydrate is as selenium source, thiohydracrylic acid and Sodium hexametaphosphate 99 are double complexing agents, utilize hydrazine hydrate to reduce method one step of Sodium selenite (Na2SeO3) pentahydrate in the aqueous solution and prepare the water-soluble CdSe quantum dot; Step is as follows:
(1) add successively Sodium hexametaphosphate 99 and thiohydracrylic acid in the cadmium chloride solution that is 1.0-5.0 mM/l to concentration under room temperature, the mol ratio of Cadmium chloride fine powder and Sodium hexametaphosphate 99 is 1:(0.7-4), the mol ratio of Cadmium chloride fine powder and thiohydracrylic acid is 1:(1-4), adition process is carried out under magnetic agitation, after thiohydracrylic acid adds end, solution acidity is adjusted to pH=7-9, obtains the precursor solution of cadmium;
(2) under the magnetic agitation condition, add Sodium selenite (Na2SeO3) pentahydrate in the precursor solution of the cadmium made to step (1), the mol ratio of Cadmium chloride fine powder and Sodium selenite (Na2SeO3) pentahydrate is 1:(0.02-0.15);
(3) add hydrazine hydrate in step (2) gained solution, thermostatically heating backflow 5-13 hour under 100 ° of C conditions, obtain the quantum dot solution of different fluorescent emission wavelength; Cadmium chloride fine powder and hydrazine hydrate mol ratio are 1:(200-400);
(4) step (3) gained water-soluble CdSe quantum dot solution is centrifugal with the rotating speed of 7500 ~ 8000 rev/mins, after removing supernatant liquid, the gained precipitation is dispersed in acetone, centrifugation three times, finally will be precipitated and dissolved in water, obtain the water-soluble CdSe quantum dot.
2. the preparation method of a kind of water-soluble CdSe quantum dot as claimed in claim 1, is characterized in that, in described step (1), the mol ratio of Cadmium chloride fine powder and Sodium hexametaphosphate 99 is 1:(0.7-2.1), the mol ratio of Cadmium chloride fine powder and thiohydracrylic acid is 1:(1-3).
3. the preparation method of a kind of water-soluble CdSe quantum dot as claimed in claim 1 or 2, is characterized in that, in described step (1), the mol ratio of Cadmium chloride fine powder and Sodium hexametaphosphate 99 is 1:2.1, and the mol ratio of Cadmium chloride fine powder and thiohydracrylic acid is 1:2.5.
4. the preparation method of a kind of water-soluble CdSe quantum dot as claimed in claim 1, is characterized in that, in described step (2), the mol ratio of Cadmium chloride fine powder and Sodium selenite (Na2SeO3) pentahydrate is 1:(0.02-0.10).
5. the preparation method of a kind of water-soluble CdSe quantum dot as claimed in claim 1, is characterized in that, in described step (3), the mol ratio of Cadmium chloride fine powder and hydrazine hydrate is 1:260.
6. the preparation method of a kind of water-soluble CdSe quantum dot as claimed in claim 1, is characterized in that, the time that in described step (3), thermostatically heating refluxes is 5-10 hour.
7. the preparation method of a kind of water-soluble CdSe quantum dot as claimed in claim 1, is characterized in that, in described step (2), the mol ratio of Cadmium chloride fine powder and Sodium selenite (Na2SeO3) pentahydrate is 1:0.05.
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Application publication date: 20121107 Assignee: Shandong Guochen Biotechnology Co.,Ltd. Assignor: SHANDONG University Contract record no.: X2021370000028 Denomination of invention: A preparation method of water-soluble CdSe quantum dots Granted publication date: 20140108 License type: Common License Record date: 20210928 |