KR20120076709A - A quantum dot manufacturing method - Google Patents

Abstract

PURPOSE: A manufacturing method of quantum dot is provided to easily control the size of quantum dot according to intensity and irradiation time of electron beam, to easily manufacture quantum dot and quantum rod, and to improve working efficiency. CONSTITUTION: A manufacturing method of quantum dot comprises: a step of obtaining solution by dispersing metal of group 12, or metal precursor of group 12 into distilled water; a step of obtaining solution in which thiol comprising mercapto group, or dithiol ligand is sprayed into a distilled water; a step of mixing and stirring respective solution; and a step of irradiating the mixed solution with electron beam; and the metal of group 12 consists of one selected from Cd, Zn, and Hg. In the first step, the size of the quantum dot is varied according to the concentration of the group 12 metal or the group 12 metal precursor.

Description

Quantum dot manufacturing method

The present invention relates to a quantum dot manufacturing method, and more particularly to a quantum dot manufacturing method that can control the size of the quantum dot and the quantum rod in a simple manner.

When the compound semiconductor material is made of nano-sized crystals, the quantum confinement effect is shown in the region smaller than the bulk exciton bohr radius of the material. The band gap energy that appears as will change. When the original compound semiconductor material emits light in the visible region, when it is made of nanocrystals and enjoys the size, the band gap energy begins to change below a certain size, and the energy gradually increases, and the emission region moves to the blue region. A blue shift is observed. By using the properties of the quantum dot material, it is possible to create a variety of energy levels by adjusting the band gap by adjusting the properties, structure, shape, size of the material itself.

Quantum dot growth control technology is attracting attention as the most important technology in the development of new concept future semiconductor devices. In particular, conventional vapor deposition methods such as MOCVD and MBE can control semiconductor thin films at the level of a single atomic layer, and can be said to be good growth technologies for growing and controlling quantum dots.

However, the above-described prior art has the following problems.

In the case of manufacturing the quantum dots in the same manner as in the prior art, there are many variables to manufacture the quantum dots, so that the size of the quantum dots cannot be easily controlled, and there is a problem that the quantum dots are made variously regardless of the operator's request, resulting in low manufacturing efficiency. . Therefore, colloidal chemical synthesis is the most suitable method for controlling the size and shape of nanocrystals in order to prepare nanocrystals for high quality.

Accordingly, an object of the present invention is to solve the problems of the prior art as described above, and to provide a one-pot synthesis method of quantum dot production that can easily control the growth size of the quantum dot by a water-soluble method through electron beam irradiation.

 According to a feature of the present invention for achieving the above object, the present invention is a method for producing a quantum dot, the first step of obtaining a solution by dispersing a Group 12 metal or Group 12 metal precursor in distilled water, and a mercapto group And a third step of obtaining a solution in which thiol or dithioligand is injected into distilled water, a third step of mixing and stirring the respective solutions, and a fourth step of irradiating an electron beam to the mixed solution. have.

In the quantum dot manufacturing method according to the present invention has the following effects.

Since the manufacturing process of the quantum dot is made simple, the size of the quantum dot can be easily adjusted according to the intensity and irradiation time of the electron beam, so that the quantum dot and the quantum rod having a desired size can be easily manufactured, thereby increasing work efficiency.

1 is a flow chart showing the procedure of the quantum dot manufacturing method according to the present invention.
2a to 2c is a view showing an experimental example of a quantum dot and a quantum nano-rod manufactured by the method for manufacturing a quantum dot according to the present invention.
Figure 3 is an FT-IR diagram showing the bonding and separation state of the SH bond and CdS bond by the quantum dot manufacturing method according to the present invention.

Hereinafter, a preferred embodiment of the quantum dot manufacturing method according to the present invention will be described in detail with reference to the accompanying drawings.

In the present invention, the method for preparing a quantum dot, as shown in FIG. And a second step, a third step of mixing and stirring the respective solutions, and a fourth step of irradiating an electron beam to the solution.

First, in the quantum dot manufacturing method of the present invention, a Group 12 metal or a Group 12 metal precursor is used. Examples of the Group 12 metals include Cd, Zn, Hg, and the like, or a mixture thereof may be used.

In addition, the Group 12 metal precursor is, for example, CdCl ₂ , Cd (OH) ₂ , CdO, CdSO ₄ , C ₄ H ₆ CdO _4? 2H ₂ O, Cd (CH ₃ ) ₂ , Cd (NO ₃ ) _2? It may be composed of any one or more of 4H ₂ O.

Here, it is preferable to use the CdCl ₂ . This is to cause a reaction with the chloride of the mercapto group when mixed in the fourth step described below.

First, the bromide of the Group 12 metal is dispersed in water to make a bromide solution of the Group 12 metal (hereinafter referred to as a first solution). At this time, the water is preferably distilled water. This is to prevent other reactions from being mixed with the foreign matter in the water.

Then, a solution containing a ligand of thiol or dithiol containing a mercapto group for reaction with the Group 12 metal precursor is made (hereinafter referred to as a second solution). The chloride of the mercapto group is to react with the Group 12 metal to form a quantum dot.

The diol or dithiol containing the mercapto group is, for example, 2,3-dimercapto-1-prophenol (2,3-Dimercapto-1-propanol), 2-mercaptoethanol (2-Mercaptoethanol), It may be composed of any one or more of 1,3-propanedithiol (1,3-Propanedithiol), 3-mercaptopropionic acid (3-Mercaptopropionic acid).

The thiol or dithiol solution containing the mercapto group disperses the thiol or dithiol containing the mercapto group in an aqueous solution. At this time, the water is preferably dispersed in distilled water, as in the above-described precursor of the Group 12 metal.

 In addition, the concentration of the thiol or dithiol solution containing the mercapto group may be composed of 2mM to 3mM, preferably composed of 2.5mM.

Then, the first solution and the second solution are mixed. At this time, it is preferable to stir so that the precursor of the Group 12 metal of the first solution and the ligand of the thiol or dithiol of the second solution may be evenly mixed with each other. The stirring process is preferably stirred for 30 minutes to 10 hours at the laboratory temperature.

When the stirring is finished, the mixed solution is irradiated with an electron beam. The reason for irradiating the electron beam is to cause the Group 12 metal of the Group 12 metal precursor and the S of the mercaptan group to react, for example, to form CdS.

The electron beam may irradiate the mixed solution at a dose of 10 to 300 kGy at an energy of 0.1 MeV to 10 MeV.

As the size of the CdS molecule increases by the above-described process, quantum dots are formed and quantum nanorods are made. At this time, by the electron beam, only the CdS molecules remain in the bond between the group 12 metal Cd and the mercapto group, and the remaining part is cut by the electron beam.

This can be seen from the upper end of FIG. 3 before the electron beam irradiation and the lower end of FIG. 3 after the electron beam irradiation, where the SH bond disappears and the bond band of CdS appears.

Here, the size and length of the CdS may be controlled due to the difference in concentration between the first solution and the second solution. Hereinafter, a method of controlling the size and length of the CdS will be described in detail.

As shown in Figure 2a to 2c, in the present experiment is to fix the second solution of the first solution and the second solution and to adjust the concentration of the first solution. Of course, the concentration of the first solution may be fixed and the concentration of the second solution may be adjusted.

In this experiment, the concentrations of the first solution were 0.4 mM, 2 mM, and 5 mM, and the second solution was fixed at 2.5 mM. As shown in FIG. 2A, when the concentration of the first solution is 0.4 mM, it can be seen that quantum dots are formed.

And, as shown in Figure 2b, it can be seen that when the concentration of the first solution is 2mM, it is relatively larger than the 0.4mM of the quantum dot. As shown in FIG. 2C, when the concentration of the first solution is 5 mM, it can be seen that a quantum nanorod is formed as the quantum dot increases.

It is to be understood that the invention is not limited to the disclosed embodiment, but is capable of many modifications and variations within the scope of the appended claims. It is self-evident.

Claims (5)

A first step of dispersing a Group 12 metal or Group 12 metal precursor in distilled water to obtain a solution;
A second step of obtaining a solution obtained by spraying thiol or dithioligand including a mercapto group in distilled water;
A third step of mixing and stirring the respective solutions; And,
And a fourth step of irradiating the mixed solution with an electron beam. The method of claim 1,
The Group 12 metal,
Qd, Zn, Hg quantum dot manufacturing method characterized in that it is composed of any one. The method of claim 1,
In the first step,
A method of manufacturing a quantum dot, characterized in that the size of the quantum dot is changed by varying the concentration of the Group 12 metal or Group 12 metal precursor. According to claim 1,
In the second step,
Quantum dot manufacturing method characterized in that the stirring for 30 minutes to 10 hours. The method of claim 1,
In the third step,
A method for manufacturing a quantum dot, characterized in that for irradiating an electron beam of 0.1 to 10-MeV.

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