KR20120113334A - Water soluble nano phosphor and process for producing the same - Google Patents

Abstract

PURPOSE: A water-soluble nanophosphor is provided to have excellent stability of dispersion and low toxicity by surface-modifying manganese ion-doped zinc sulfide nanocrystals by water-soluble polymers and to be usable in various medical fields and environmental-friendly electronic material fields. CONSTITUTION: A water-soluble nanophosphor comprise manganese ion-doped zinc sulfide(Zns:Mn) nanocrystals and one or more kinds of polymers selected form polyethylene oxide, polypropylene oxide, polytetramethyleneoxide and polyalkyleneoxide combined to the surface of the nanocrystals. The weight average molecular weight of the polyethylene oxide, polypropylene oxide, polytetramethyleneoxide and polyalkyleneoxide is 1,000-500,000. In the nanocrystals 0.01-1 parts by mole of manganese ion are doped based on 100.0 parts by mole. The average size of the water-soluble nanophosphor is 1-50 nm.

Description

Water-soluble nanophosphor and its manufacturing method {WATER SOLUBLE NANO PHOSPHOR AND PROCESS FOR PRODUCING THE SAME}

The present application relates to a nanophosphor and a method for manufacturing the same, and more particularly, to a water-soluble nanophosphor and a method for producing the surface modified with a polymer.

Semiconductor nanocrystals have been widely studied because of their photochemical properties according to their size and various applications. The specific chemical and physical properties of these nanocrystals are determined by their shape and size. Thus, over the last few decades, much research has been done to determine the chemical and physical properties of materials that change when these crystals form crystals at the 1-100 nm level. In particular, research has been focused on forming a quantum well of several nanometers on a substrate using a technique such as metal organic chemical vapor deposition.

Quantum wells consist of two materials with different bandgaps in the form of sandwiches, which can be arranged in a variety of ways depending on the purpose of the study. The thickness of the material deposited in the middle is about several nanometers, and when the thickness is smaller than the Bohr Radius of the exciton formed by the excited electrons and holes, the Quantum Confinement Effect in the thickness direction. The excitons are trapped in the middle semiconductor layer and exhibit high photoluminescence efficiency because of the larger band gap and the larger band gap of the material in the outer part of the quantum well structure.

In the case of quantum dots, the zero-dimensioin, in which semiconductor crystals take the form of spheres, causes quantum-limiting effects in all directions in three dimensions. The characteristics change greatly. The research on these semiconductor nanocrystals has been particularly focused on group II-VI semiconductor compounds. The quantum dots using group II-VI compound semiconductor composition composed of group II elements (Zn, Cd, etc.) and group VI elements (S, Se, Te, etc.) on the periodic table have high luminous efficiency, light stability, and Much research has been carried out as a material that can emit light. As the bandgap of the group II-VI semiconductor bulk material is heavier, the bandgap becomes narrower and the absorption and emission wavelength become longer. If the size is reduced from the bulk to the area of the nanoparticles, the band gap is widened by the quantum size effect, and thus the light emission wavelength can be finely adjusted through the small change of the particle size.

At the nanometer scale, we can see a variety of phenomena not seen in conventional materials. Semiconductor nanocrystal phosphors change the color of fluorescence as they adjust their size, and nanocrystals with magnetic properties change their magnetization according to their size and even completely change their magnetic properties from ferromagnetic to superparamagnetic. In addition, since the surface area is very large compared to a very small volume, it is also attracting attention as an economical catalyst material that can be applied to various chemical industries such as petrochemical process and pharmaceutical synthesis. Therefore, researches on various industrial applications such as light emitting diodes, solar cells and memory devices have been conducted for the past 10 years.

As such, the quantum dots that are nanocrystals have a broad absorption spectrum, a narrow emission band, excellent excitation coefficient, and excellent photostability. These properties allow quantum dots to be used in the bio and medical fields, such as sensing, marking, optical imaging, cell separation, and diagnostics. However, for such applications, there is a problem in that quantum dots must be well dispersed in water and stable.

In addition, conventionally used fluorescent materials such as CdSe or CdS, which emits light of various wavelengths and absorbs the full range of visible light depending on the size, so they are widely used in electronic materials such as inorganic EL and light conversion materials, or toxic. Since it contains a cadmium ion, which is a substance, it is not suitable for application in the biological and medical fields, and there is a problem that the application may be limited due to environmental regulations in the material field.

Therefore, the present invention is to solve the above-mentioned problems of the prior art, and the first object of the present invention is to change the surface of the manganese ion-doped zinc sulfide (ZnS: Mn) nanocrystals into water-soluble by changing the water-soluble in water It is to provide a water-soluble nano-phosphor that can be used in the medical field or the electronic material field because the dispersion is excellent in stability, low toxicity and environmentally friendly dispersion.

The second object of the present invention is to provide a method for producing a water-soluble nanophosphor that is simple and eco-friendly by producing a water-soluble nanophosphor using water as a solvent.

As a technical means for achieving the above technical problem, one aspect of the present invention, zinc sulfide (ZnS: Mn) nanocrystals doped with manganese ions; And at least one polymer selected from the group consisting of polyethylene oxide, polypropylene oxide, polytetramethylene oxide and polyalkylene oxide bonded to the surface of the nanocrystal.

In addition, the polymer may be preferably polyethylene oxide.

In addition, the nanocrystals may be doped with the manganese ions 0.01 to 1 mole parts based on 100 mole parts of the zinc sulfide.

In addition, the polyethylene oxide, polypropylene oxide, polytetramethylene oxide or polyalkylene oxide may have a weight average molecular weight of 1,000 to 500,000.

In addition, the nanocrystals may be a wurtzite or zinc blende structure.

In addition, the water-soluble nanophosphor may have an average size of 1 to 50nm.

Another aspect of the present invention is zinc sulfide (ZnS: Mn) nanocrystals doped with manganese ions; And one or more polymers selected from polyethylene oxide, polypropylene oxide, polytetramethylene oxide, and polyalkylene oxide bonded to the surface of the nanocrystal, zinc sulfate (ZnSO _{4) in} water ); Manganese sulfate (MnSO ₄ ); Dissolving at least one polymer selected from polyethylene oxide, polypropylene oxide, polytetramethylene oxide and polyalkylene oxide to prepare a mixed aqueous solution (a) and adding sodium sulfide (Na ₂ S) to the mixed aqueous solution; Reaction provides a method for producing a water-soluble nanophosphor comprising the step (b) of preparing a water-soluble nanophosphor.

The step (a) may be a step of dissolving 0.01 to 1 mole parts of manganese sulfate (MnSO ₄ ) based on 100 mole parts of zinc sulfate (ZnSO ₄ ) in water to prepare a mixed aqueous solution.

The method of manufacturing the water-soluble nanophosphor may further include bubbling the mixed aqueous solution with nitrogen or an inert gas in step (a) or after step (a).

The step (b) may be a step of preparing a water-soluble nanophosphor by adding sodium sulfide (Na ₂ S) to the mixed aqueous solution and reacted while refluxing (reflux).

In the method of manufacturing the water-soluble nanophosphor, the polymer may be preferably polyethylene oxide.

In the method of manufacturing the water-soluble nanophosphor, the polyethylene oxide, polypropylene oxide, polytetramethylene oxide or polyalkylene oxide may have a weight average molecular weight of 1,000 to 500,000.

In the method of manufacturing the water-soluble nanophosphor, the nanocrystals may be a wurtzite or zinc blende structure.

In the method of manufacturing the water-soluble nanophosphor, the water-soluble nanophosphor may have an average size of 1 to 50nm.

Therefore, in the present invention, since the surface of the manganese ion-doped zinc sulfide (ZnS: Mn) nanocrystals are converted into water-soluble polymers by surface modification, they are well dispersed in water, so the dispersion is excellent in stability, low toxicity, and environmentally friendly. It is possible to provide a water-soluble nanophosphor that can be used in the field or environmentally friendly electronic materials.

In addition, the present invention can provide a method for producing a water-soluble nano-phosphor is simple and environmentally friendly by synthesizing a water-soluble nano-phosphor using water as a solvent.

FIG. 1 shows Examples 1 (a), 2 (b), 3 (c), 4 (d), 5 (e) and 6 (f) measured at room temperature. The emission spectrum picture of the nanophosphor.
2 shows nanoparticles according to Example 1 (a), Example 2 (b), Example 3 (c), Example 4 (d), Example 5 (e) and Example 6 (f) of the present invention. High-resolution electron transmission microscope (HR-TEM) images of the phosphors are shown, respectively, and the scale bar at the lower left is a photo showing 5 nm.
3 shows nanoparticles according to Example 1 (a), Example 2 (b), Example 3 (c), Example 4 (d), Example 5 (e) and Example 6 (f) of the present invention. Energy-dispersive X-ray spectroscopy (EDXS) of the phosphor.
4 is a view showing the FT-Raman spectrum (a) and the FT-Raman spectrum (b) of uncoordinated polyethylene oxide having a weight average molecular weight of 35,000 of the nanophosphor of Example 4.
5 shows the nanophosphor of Example 1 (a), Example 2 (b), Example 3 (c), Example 4 (d), Example 5 (e), and Example 6 (f), and (g) ) XRD pattern of ZnS wurtzite.

DETAILED DESCRIPTION Hereinafter, embodiments and embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention.

However, the following description is not intended to limit the present invention to specific embodiments, and it should be understood that the present invention covers all the transformations, equivalents, and substitutes included in the spirit and scope of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

As a technical means for achieving the above technical problem, one aspect of the present invention is zinc sulfide (ZnS: Mn) nanocrystals doped with manganese ions; And at least one polymer selected from the group consisting of polyethylene oxide, polypropylene oxide, polytetramethylene oxide and polyalkylene oxide bonded to the surface of the nanocrystal.

Nanocrystals

Quantum dots, nanocrystals synthesized by chemical methods, are discontinuous, like individual discrete atoms, unlike bulk semiconductor crystals, because the exciton that pairs electrons and holes is spatially limited by smaller nanocrystals. It is also called an artificial atom because it has a band structure. In addition, the quantum dot has a ligand coordinated to the surface, it is possible to make the desired organic functional group on the surface through a suitable chemical reaction.

The most important reason that the industrial application of nanocrystals is difficult is that the electrical conductivity of semiconductor nanocrystals is very low to insulator level. This problem can be solved through doping. Doping is a process of injecting impurities into a semiconductor to make an insulator semiconductor into a conductive material. In the current silicon-based microprocessor, silicon is doped with boron or phosphorous to increase electrical conductivity. In the case of phosphors used in color television, oxide particles are doped with various ions to form red (R) and green (G). , It implements various colors such as blue (B). Doping refers to the process of controlling the electrical, optical, and sometimes magnetic properties of the material by intentionally injecting impurity ions into the crystal.

Zinc sulfide (ZnS) is a group II-VI semiconductor with a bandgap of 3.68 eV and direct transition. ZnS is not suitable for the emission of visible light due to its large band gap, but when doping a material such as Mn (ZnS: Mn), the band gap is controlled to absorb and emit visible light. Such as various optical applications.

The nanocrystals of the present invention are zinc sulfide (ZnS: Mn) nanocrystals doped with manganese ions. The nanocrystals may be doped with manganese ions 0.01 to 1 mole parts, more preferably 0.05 to 0.5 mole parts based on 100 mole parts of zinc sulfide. In addition, the nanocrystals may be a wurtzite or zinc blende structure.

Water soluble nanophosphor

The water-soluble nanophosphor is a zinc sulfide (ZnS: Mn) nanocrystals doped with manganese ions; And at least one polymer selected from polyethylene oxide, polypropylene oxide, polytetramethylene oxide, and polyalkylene oxide bonded to the surface of the nanocrystals. The polyethylene oxide, polypropylene oxide, polytetramethylene oxide, and polyalkylene oxide may be polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and polyalkylene glycol, respectively, depending on molecular weight. In some cases, the term “polyethylene oxide, polypropylene oxide, polytetramethylene oxide, and polyalkylene oxide” is used herein regardless of molecular weight unless otherwise specified.

In order to apply the nanocrystals as nanopharmaceuticals, a capping ligand suitable for a living body should be attached to the surface of the nanocrystals. It is a biodegradable polymer that is harmless to the human body, inhibits degradation by enzymes, inhibits absorption from kidneys and blood vessels, and prolongs residence time in the blood. , Polypropylene oxide represented by the following formula (2), polytetramethylene oxide represented by the following formula (3) or polyalkylene oxide of the following formula (4) may be used as a capping ligand, more preferably using the polyethylene oxide to the water-soluble nano Phosphors can be synthesized. In particular, polyethylene oxide can sustain long-term efficacy because it does not cause an immune response by monocytes and macrophages. In addition, since the surface of the nanocrystals is coated with the non-toxic water-soluble polymer, the toxicity of the nanocrystals may be reduced.

[Formula 1]

[Formula 2]

(3)

[Formula 4]

In Formulas 1 to 4, n is a repeating number of repeating units.

The polyethylene oxide, polypropylene oxide, polytetramethylene oxide or polyalkylene oxide may have a weight average molecular weight of 1,000 to 500,000, more preferably 1,500 to 200,00, even more preferably 20,000 to 50,000.

The water-soluble nanophosphor has an average size of 1 to 50 nm, more preferably 1 to 10 nm, more preferably 2 to 5 nm.

Another aspect of the present invention is zinc sulfide (ZnS: Mn) nanocrystals doped with manganese ions; And at least one polymer selected from polyethylene oxide, polypropylene oxide, polytetramethylene oxide, and polyalkylene oxide bonded to the surface of the nanocrystal; zinc sulfate in water (ZnSO ₄ ); Manganese sulfate (MnSO ₄ ); Dissolving at least one polymer selected from polyethylene oxide, polypropylene oxide, polytetramethylene oxide and polyalkylene oxide to prepare a mixed aqueous solution (a) and adding sodium sulfide (Na ₂ S) to the mixed aqueous solution; Reaction provides a method for producing a water-soluble nanophosphor comprising the step (b) of preparing a water-soluble nanophosphor.

(A) preparing a mixed aqueous solution

Zinc sulfate (ZnSO ₄ ) in water; Manganese sulfate (MnSO ₄ ); A mixed aqueous solution may be prepared by dissolving at least one polymer selected from polyethylene oxide, polypropylene oxide, polytetramethylene oxide, and polyalkylene oxide. It is preferable to stir in order to mix.

In step (a), 0.01 to 1 mol parts of manganese sulfate (MnSO ₄ ) may be dissolved in water based on 100 mol parts of zinc sulfate (ZnSO ₄ ).

In the method for preparing the water-soluble nanophosphor, it is more preferable to remove the air by bubbling the mixed aqueous solution with nitrogen or an inert gas after the step (a) or after the step (a).

(B) preparing a water-soluble nanophosphor

A water-soluble nanophosphor may be prepared by adding and reacting sodium sulfide (Na ₂ S) to the mixed aqueous solution.

In the step (b), it is more preferable to prepare a water-soluble nanophosphor by adding sodium sulfide (Na ₂ S) to the mixed aqueous solution and reacting with reflux. The reaction can be carried out for 5 to 48 hours, more preferably 15 to 30 hours while refluxing.

In the method of manufacturing the water-soluble nanophosphor, the polymer, the nanocrystal and the water-soluble nanophosphor are the same as described above.

Hereinafter, the configuration of the present invention will be described in more detail with reference to the following examples, but is not limited thereto.

[Example]

Although an Example demonstrates this invention concretely, this invention is not restrict | limited to the following Example.

Reagents used in the synthesis of the water-soluble nanophosphor of the present invention are as follows.

Zinc sulfate, ZnSO ₄ ? H ₂ O, Duksan

Manganese sulfate Dried, MnSO ₄ , 98.5%, Duksan

Polyethylene oxide (weight average molecular weight, Mw: 1500, 4000, 10000, 35000, 100000, 200000, Aldrich)

Sodium sulfide hydrate (Na ₂ S? Aq, Fluka)

Ethyl alcohol (C ₂ H ₆ O, 99.9%, Duksan)

Example  One

A mixed solution of 1M ZnSO ₄ (5 mL), 0.1 M MnSO ₄ (1.5 mL), and polyethylene oxide (PEO, weight average molecular weight Mw = 1,500) in 45.5 mL of distilled water was bubbling with Ar gas for 30 minutes to remove air. . Quickly 1M Na ₂ S (4.5 mL) was added and refluxed for 20 hours. After the temperature was lowered to room temperature, ethanol (Ethanol) was added to precipitate and centrifuged to obtain a white powder, which is a water-soluble nanophosphor. It was washed several times and dried in a vacuum oven.

Example  2

It is the same as Example 1 except that polyethylene oxide (PEO, weight average molecular weight Mw = 4,000) is used instead of polyethylene oxide (PEO, weight average molecular weight Mw = 1,500).

Example  3

It is the same as Example 1 except that polyethylene oxide (PEO, weight average molecular weight Mw = 10,000) was used instead of polyethylene oxide (PEO, weight average molecular weight Mw = 1,500).

Example  4

It is the same as Example 1 except that polyethylene oxide (PEO, weight average molecular weight Mw = 35,000) was used instead of polyethylene oxide (PEO, weight average molecular weight Mw = 1,500).

Example  5

It is the same as Example 1 except that polyethylene oxide (PEO, weight average molecular weight Mw = 100,000) is used instead of polyethylene oxide (PEO, weight average molecular weight Mw = 1500).

Example  6

It is the same as Example 1 except that polyethylene oxide (PEO, weight average molecular weight Mw = 200,000) was used instead of polyethylene oxide (PEO, weight average molecular weight Mw = 1500).

UV / Visible Spectroscopy

Ultraviolet / vis spectrometer (UV / Vis spectrometer, Perkin-Elmer Lambda 25) was used to investigate the absorption wavelength of synthesized ZnS: Mn nanoparticles, and deuterium and tungsten lamps were used as light sources.

Fluorescence spectroscopy

Fluorescence spectrophotometer (HITACHI F-7000 Fluorescence Spectrophotometer) was used to know the excitation wavelength and emission wavelength. And Photomultiplier tube.

X-ray powder diffraction  Analyzer

X-ray powder diffractometer (XRD), Japan Rigaku DMAX-IIIA) was used to confirm the crystal structure of the nanoparticles, and Cu-K was used as the light source.

High resolution electron transmission microscope HR - TEM )

HR-TEM images for particle size and shape were measured with a JEOL JEM 3010 electron microscope. This model is a high-resolution transmission electron microscope with an acceleration voltage of 300 kV, which is excellent for microstructure observation compared to a general TEM, and is suitable for observation of atomic images and crystallographic analysis. The obtained nanophosphor quantum dots were dispersed in methanol, dropped onto a copper-coated copper grid, and dried in vacuum to prepare a sample for TEM. In addition, the EDS collecting unit (Si detector) equipped with HR-TEM was equipped with Gatan digital camera, enabling the component analysis using X-ray on the characteristics of the sample on the TEM, and obtained digital image file in real time. .

ICP - Atomic Emission Spectrometer

Perkin Elmer's OPTIMA 4300UV and ICP-Atomic Emission Spectrometer were used to quantitatively and qualitatively analyze the elements of the nanoparticles.

Raman spectroscopy ( Fourier transform - Raman spectroscopy )

The molecular structure of PEO binding to nanoparticles was confirmed by Fourier transform-Raman spectroscopy (FT-Raman) (Bruker FRA 106 / S).

UV Of Vis spectro - photomete

A UV / Vis spectrophotometer (Mecasys, Korea) of O. D. 600 nm was used for cytotoxicity measurement according to the quantum dot concentration.

Cytotoxicity ( cytotoxicity ) Measure

The types of mammalian cells used were IMR909 (Lung Fibgoblast), HEK293 (Human Embryonic Kidney), and HUVEC (Human Umbilical Vein Endotshelial Cell). Treat the drug in the cell and perform the WST-1 assay. The WST-1 kit makes it easier to measure viability of cells. In addition, cytotoxicity can be measured simply and quickly by measuring LDH released from damaged cells. Therefore, the WST-1 kit is mainly used to measure cell proliferation, viability or cytotoxicity. WST-1 assay can be measured accurately and can be performed faster than conventional MTT method and can be measured with a small amount of cells. When treated with mitochonrial succinate-tetrazolium reductase in the WST-1 kit, it becomes formazan. At this time, it turns from pale red color to dark red color.

(a) The mechanism of WST-1 assay

(b) Experimental schemes of cytotoxicity measurement

1 is an emission spectrum of ZnS: Mn-PEO nanocrystals measured at room temperature. The light was emitted in an orange region of 605 nm. When the molecular weight of PEO was 35,000, the fluorescence appeared the strongest, and when the molecular weight was higher than that, the fluorescence was reduced. In order to confirm this more accurately, the fluorescence efficiency was calculated.

Generally, fluorescence in fluorescence or quantum yield means the ratio of the number of photons absorbed and the number of photons emitted when a fluorescence phenomenon takes place by giving light, and between 0 and 1 in fluorescence. In general, the fluorescence efficiency of the nanoparticles in the colloidal state of the aqueous solution is calculated relative to the fluorescence efficiency compared to the organic phosphor known in the known quantum efficiency. In the case of ZnS: Mn-PEO nanocrystals synthesized in this study, quinine sulfate was used, which has the highest absorption and emission wavelength band among the known organic fluorescent materials.

A standard solution was prepared by dissolving quinine sulfate in 0.1 M H ₂ SO ₄ solution. And after adjusting the ZnS: Mn-PEO nano-phosphor particles and the UV absorbance value, fluorescence was taken to compare the integral value.

[Formula 1]

In Equation 1 above, Φ _X represents quantum yield, Φ _ST represents quantum yield of standard quinine 0.54, Grad _X represents integral value of quantum dots, Grad _ST represents integral value of quantum dots, and η _X represents quantum dot solvent. The refractive index, η _ST , represents the refractive index of the solvent in the standard solution. Here, the refractive index (reflective index) is different for each solvent, because both the quinine and ZnS: Mn-PEO solvent is water, the refractive index was calculated to 1 and the quantum efficiency was measured.

The fluorescence efficiencies obtained were 1.9% (PEO 1500), 1.76% (PEO 4,000), 5.3% (PEO 10,000), 5.9% (PEO 35,000), 2.5% (PEO 100,000), and 2.7% (PEO 200,000).

The shape and size of the quantum dots were confirmed by high resolution electron transmission microscope (HR-TEM) image (FIG. 2). The ZnS: Mn-PEO nanoparticles were all spherical, with an average size of 3.1 nm and almost no change in size of the nanoparticles depending on the molecular weight of PEO, with a standard deviation of 1.1.

The element ratio of the quantum dots was confirmed by energy-dispersive X-ray spectroscopy (EDXS) (FIG. 3). It was confirmed that the quantum dot is composed of Zn, S, and Mn. ICP-AES was used to accurately measure the proportion of manganese-doped quantum dots [mole%, manganese moles / (manganese moles + zinc moles)]. Table 1 shows that about 0.1-0.4 mol% of manganese was doped.

Example Weight average molecular weight (Mw) of polyethylene oxide Zn (ppm) Mn (ppm) One 1,500 589.96 1.97 2 4,000 606.54 1.37 3 10,000 569.75 1.31 4 35,000 569.36 1.40 5 100,000 540.37 0.79 6 200,000 750.45 1.05

The morphology of ZnS: Mn nanoparticles adsorbed by PEO could be predicted by Raman spectroscopy. Raman spectra of PEO and ZnS: Mn-PEO were compared. In FIG. 4, the OH stretching method 2683 cm ⁻¹ and the COH bending motion 1394 cm ⁻¹ do not exist, indicating that the PEO was bonded after the hydrogen dropped off the surface of the nanoparticles. Table 2 assigns the Raman spectrum of ZnS: Mn-PEO of PEO and Example 4.

PEO ZnS: Mn-PEO35,000 TO (ZnS) 261 LO (ZnS) 346 δ (C-C-O) 361 420 do. 534 610 ν (C-C) 842 848 ρ (CH ~) 858 989 ν (C-O) 1060 1040 ω (CH ...) 1279 1280 δ (C-O-H) 1394 δ (CH ² ) 1479 1470 ν (O-H) 2683 ν (C-H) sym. 2884 ν (C-H) anti-sym. 2942

XRD was measured to confirm the structural properties of the ZnS: Mn-PEO nanoparticles (FIG. 5). Bulk ZnS has a wurtzite structure. Comparing the synthesized nanoparticles of Example 4 with bulk ZnS, it was confirmed that ZnS: Mn-PEO also has a wurtzite structure.

When the surface was modified with polyethylene oxide, it was well dispersed in water, and the dispersion was stable even under conditions of 10 atm and 120 ° C.

Cytotoxicity was measured using mammailan cells for biological applications. As the molecular weight of PEO increases, the concentration of nanophosphor increases, the toxicity increases. No toxicity was shown up to 10 ug / mL.

The experimental results are shown in Table 3.

Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Weight average molecular weight of PEO  1,500 4,000 10,000 35,000 100,000 200,000 UV / Vis
(λ max, nm) 332 333 331 334 333 335 PL
emission wavelength (nm) 603 602 604 603 604 605 PL
Efficiency (%) 1.9 1.76 5.3 5.9 2.5 2.7 FT-IR
(cm ^-1 ) 3184 (m),
2164 (w),
1632 (m),
1454 (w),
1348 (w),
1100 (s),
1050 (s),
980 (m) 3196 (m),
2164 (w),
1636 (m),
1468 (w),
1350 (w),
1108 (s),
1062 (s)
980 (m) 3178 (m),
2168 (w),
1626 (m),
1468 (w),
1350 (w),
1108 (s),
1062 (s),
980 (m) 3144 (m),
2162 (w),
1626 (m),
1454 (w),
1346 (w),
1104 (s),
1042 (s),
980 (m) 3190 (m),
2164 (w),
1624 (m),
1452 (w),
1348 (w),
1098 (s),
1046 (s),
980 (m) 3184 (m),
2160 (w),
1636 (m),
1456 (w),
1346 (w),
1106 (s),
1052 (s),
984 (m) Raman
(cm ^-1 ) 262 (s),
343 (m),
428 (w),
615 (w),
989 (s),
1041 (w),
1148 (w),
1281 (m),
1474 (w) 261 (s),
344 (m),
417 (w),
989 (s),
1040 (w),
1126 (w),
1279 (m),
1473 (w) 262 (s),
345 (m),
415 (w),
614 (w),
841 (w),
990 (s),
1047 (w),
1137 (w),
1279 (m)
1472 (w) 261 (s),
346 (m),
420 (w),
610 (w),
848 (w),
989 (s),
1040 (w),
1134 (w),
1280 (m),
1470 (w) 262 (s),
342 (m),
411 (w),
608 (w),
816 (w),
990 (s),
1052 (w),
1130 (w),
1288 (m) 264 (s),
348 (m),
440 (w),
606 (w),
843 (w),
989 (s),
1053 (w),
1146 (w),
1278 (m)
1449 (w) HR-TEM image
(Average particle size, nm) 3.2 3.4 2.9 3.2 2.8 3.0

The foregoing description of the present invention is intended for illustration, and it will be understood by those skilled in the art that the present invention may be easily modified in other specific forms without changing the technical spirit or essential features of the present invention. will be. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is defined by the appended claims rather than the detailed description and all changes or modifications derived from the meaning and scope of the claims and their equivalents are to be construed as being included within the scope of the present invention do.

Claims (14)

Zinc sulfide (ZnS: Mn) nanocrystals doped with manganese ions; And
At least one polymer selected from polyethylene oxide, polypropylene oxide, polytetramethylene oxide, and polyalkylene oxide bonded to the surface of the nanocrystals;
Water-soluble nanophosphor containing. The water-soluble nanophosphor of claim 1, wherein the polymer is polyethylene oxide. The water-soluble nanophosphor of claim 1, wherein the nanocrystal is doped with 0.01 to 1 mole part of the manganese ion based on 100 mole parts of zinc sulfide. The water-soluble nanophosphor according to claim 1, wherein the polyethylene oxide, polypropylene oxide, polytetramethylene oxide or polyalkylene oxide has a weight average molecular weight of 1,000 to 500,000. The water-soluble nanophosphor of claim 1, wherein the nanocrystals have a wurtzite or zinc blende structure. The water-soluble nanophosphor of claim 1, wherein the water-soluble nanophosphor has an average size of 1 to 50 nm. Zinc sulfide (ZnS: Mn) nanocrystals doped with manganese ions; And one or more polymers selected from polyethylene oxide, polypropylene oxide, polytetramethylene oxide, and polyalkylene oxide bonded to the surface of the nanocrystals.
Zinc sulfate (ZnSO ₄ ) in water; Manganese sulfate (MnSO ₄ ); (A) dissolving one or more polymers selected from polyethylene oxide, polypropylene oxide, polytetramethylene oxide, and polyalkylene oxide;
(B) preparing a water-soluble nanophosphor by adding sodium sulfide (Na ₂ S) to the mixed aqueous solution and reacting the same.
Method for producing a water-soluble nanophosphor comprising. The method of claim 7, wherein the step (a) is a step of dissolving 0.01 to 1 mol parts of manganese sulfate (MnSO ₄ ) based on 100 mol parts of zinc sulfate (ZnSO ₄ ) in water to prepare a mixed aqueous solution. Method for producing nanophosphor. 8. The method of claim 7, further comprising bubbling the mixed aqueous solution with nitrogen or an inert gas after step (a) or after step (a). 9. The method of claim 7, wherein the step (b) is the step of adding a sodium sulfide (Na ₂ S) to the mixed aqueous solution and reacting while reflux (reflux) to prepare a water-soluble nano-phosphor, characterized in that Manufacturing method. 8. The method of claim 7, wherein the polymer is polyethylene oxide. The method of claim 7, wherein the polyethylene oxide, polypropylene oxide, polytetramethylene oxide or polyalkylene oxide has a weight average molecular weight of 1,000 to 500,000. The method of claim 7, wherein the nanocrystals have a wurtzite or zinc blende structure. The method of claim 7, wherein the water soluble nanophosphor has an average size of 1 to 50 nm.

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