TWI571302B - Manufacturing method of nano material - Google Patents

Description

Method for manufacturing nano material

This invention relates to a method of making a nanomaterial, and more particularly to a method of making a nanomaterial by plasma treatment.

A nanomaterial with a quantum dot of zero dimension whose size is defined as a particle size smaller than 100 nm. In recent years, quantum dots have been gradually observed because their particle size is extremely small, and electrons are bound by quantum confinement to produce similar properties to semiconductors. Quantum dot materials with energy gap characteristics can be widely used in biomedical, solar cells and electronic components. Most of the applications in biomedicine are used in sensing elements or imaging systems, mainly using the fluorescent properties of quantum dots. The fluorescence properties of quantum dots are controlled by the size of the energy gap, so it is especially important for the control of the energy gap. The influencing factors are mainly the size of the quantum dots and the type and content of their surface functional groups.

Current methods for synthesizing quantum dots are mainly divided into bottom-up and top-down methods. Top-down methods include laser cutting, chemical redox, microwave synthesis, hydrothermal, and the like. However, the use of a top-down approach is less likely to control the size of the quantum dot product, which not only affects the phosphorescent efficacy of the material but also limits the development of its subsequent applications.

On the other hand, the bottom-up synthesis technique can be, for example, a chemical synthesis, a fullerene material cutting or the like. That is to say, it is synthesized from a unit material molecule to a large size. Therefore, the bottom-up method makes it easier to control the size of the product and its surface structure to form a quantum dot material having a uniform size.

The present invention provides a method for producing a nanomaterial by plasma treatment, which has the advantages of simple operation, fast reaction speed, and controllable structural characteristics of the nanomaterial.

The invention provides a manufacturing method for forming a nano material by plasma treatment, which can adjust quantum dot materials with different fluorescent properties, and is widely applied in different fields such as biomedical sensing components, electronic components, and energy development.

The present invention provides a method of producing a nanomaterial, the steps of which are as follows. A reaction solution is provided. The reaction solution includes at least a precursor. The reaction solution is subjected to a plasma treatment to form a plurality of nanoparticles in the reaction solution. The nanoparticles are evenly distributed in the reaction solution.

In an embodiment of the invention, the precursor comprises a carbon-containing precursor, a ruthenium-containing precursor, a cadmium-containing precursor, a lead-containing precursor, a precursor containing a Group VI material, or a combination thereof.

In an embodiment of the invention, the carbon-containing precursor comprises sodium dodecyl sulfate (SDS), Hexadecyl-trimethyl-ammonium bromide (CTAB), ten Sodium dialkyl benzene sulfonate (SDBS), citric acid, glucose (Glucose), fructose, sucrose, maltose, polyethylene glycol (PEG) or combination.

In an embodiment of the invention, the cerium-containing precursor comprises cerium tetrachloride (SiCl ₄ ), cerium tetrabromide (SiBr ₄ ), cerium oxide (SiO ₂ ), or a combination thereof.

In an embodiment of the invention, the cadmium-containing precursor comprises cadmium sulfate (CdSO ₄ ), and the lead-containing precursor comprises lead acetate (Pb(CH ₃ COO) ₂ ), lead dichloride (PbCl ₂ ) Or a combination thereof, the Group 6-containing material precursor comprises sodium selenate (Na ₂ SeSO ₃ ), sulfur powder (S), or a combination thereof.

In an embodiment of the invention, the reaction solution further includes an additive. The additives include Ethylenediamine, sec-Butylamine, Phenylenediamines, Dopamine, Potassium nitriloacetate, and Potassium Chloride (KCl). , lithium chloride (LiCl), sodium dodecyl sulfate (SDS), cetyltrimethylammonium bromide (CTAB), ethylenediaminetetraacetic acid (EDTA), thiourea (sulfourea), sodium hydroxide or combination.

In an embodiment of the invention, the reaction solution further includes an electrolyte. The electrolyte includes hydrochloric acid, sodium hydroxide or a combination thereof.

In an embodiment of the invention, the step of plasma treatment is as follows. A reaction solution was placed in the reaction apparatus. A plasma generating device is disposed on the reaction solution. The plasma generating device includes a first electrode, a second electrode, and a power supply. The power supply is electrically connected to the first electrode and the second electrode, respectively. The first electrode is immersed in the reaction solution. An inert gas is introduced into the second electrode, and the second electrode is disposed on the liquid surface of the reaction solution. The power supply is turned on so that the second electrode generates plasma in the reaction solution to synthesize the precursor into nanoparticle.

In an embodiment of the invention, the first electrode comprises a platinum electrode.

In an embodiment of the invention, the nanoparticle comprises a carbon quantum dot (CQD), a graphene quantum dot (GQD), and a silicon quantum dot (Si-dot). Cadmium selenide (CdSe) quantum dots, lead selenide (PdSe) quantum dots, lead sulfide (PdS) quantum dots or a combination thereof.

Based on the above, the present invention treats a plurality of nanoparticles in a reaction solution by plasma treatment. This embodiment has the advantage of simple operation compared to other electrochemical systems. In addition, compared with the conventional plasma, the plasma treatment of the present invention can have a higher electron density and energy per unit volume, so as to promote a faster and more diverse electrochemical reaction and non-electrochemical reaction under the liquid surface of the reaction solution. . In addition, the bottom-up method can also control the particle size and surface characteristics of the nanomaterial, and then be applied to the sensing element. Moreover, the quantum dots synthesized by the present invention have multiple emission wavelengths. Therefore, the quantum dots synthesized by the present invention can be widely applied to different fields such as biomedicine, electronic components, and energy equipment.

The above described features and advantages of the invention will be apparent from the following description.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic illustration of a reaction apparatus in accordance with one embodiment of the present invention.

Referring to FIG. 1, this embodiment provides a manufacturing method for forming a nano material by plasma treatment, and the steps are as follows. First, the reaction solution 102 is placed in the reaction apparatus 100. In one embodiment, the reaction device 100 can be, for example, a beaker, a petri dish, or other various containers suitable for containing the reaction solution 102 without chemically reacting with the reaction solution 102.

The reaction solution 102 includes at least a precursor. The precursor can be regarded as a main component of the nanomaterial to be synthesized. The precursor is contained in an amount of from 1% by weight to 20% by weight based on the total weight of the reaction solution 102. For example, if a carbon quantum dot or a graphene quantum dot is to be formed, the precursor may be, for example, a carbon-containing precursor. If a ruthenium quantum dot is to be formed, its precursor may be, for example, a ruthenium-containing precursor. If you want to form II-VI or IV-VI semiconductor quantum dots, such as cadmium selenide (CdSe) quantum dots, lead selenide (PbSe) quantum dots, lead sulfide (PbS) quantum dots, etc., the precursors can be For example, a cadmium-containing precursor, a lead-containing precursor, a precursor containing a Group VI material, or a combination thereof. However, the present invention is not limited thereto, and in other embodiments, the type of the precursor may be adjusted as needed.

In one embodiment, the carbonaceous precursor can be, for example, sodium lauryl sulfate, cetyltrimethylammonium bromide, sodium dodecylbenzene sulfonate, citric acid, glucose, fructose, sucrose, maltose, poly Ethylene glycol or a combination thereof.

In one embodiment, the ruthenium containing precursor can be, for example, ruthenium tetrachloride, ruthenium tetrabromide, ruthenium dioxide, or a combination thereof.

In an embodiment, the cadmium-containing precursor can be, for example, cadmium sulfate. The lead-containing precursor can be, for example, lead acetate, lead dichloride or a combination thereof. The precursor containing the Group 6 material can be, for example, sodium selenosulfate, sulfur powder, or a combination thereof.

In another embodiment, the reaction solution 102 may further include an additive to accelerate or cause the precursor to undergo an electrochemical reaction or a non-electrochemical reaction. The content of the additive is from 0.01 wt% to 5 wt% based on the total weight of the reaction solution 102. The additive may, for example, be ethylenediamine, secondary butylamine, phenylenediamine, dopamine, potassium nitrilotriacetate, potassium chloride, lithium chloride, sodium lauryl sulfate, cetyltrimethyl bromide Ammonium, ethylenediaminetetraacetic acid, thiourea, sodium hydroxide or a combination thereof.

In another embodiment, the reaction solution 102 may further include an electrolyte to enhance the conductivity of the reaction solution 102, so that the subsequent plasma 210 is more likely to be produced and more stable. The electrolyte is contained in an amount of 0.0001 wt% to 2 wt% based on the total weight of the reaction solution 102. The electrolyte can be, for example, hydrochloric acid, sodium hydroxide or a combination thereof.

Specifically, to synthesize different nanomaterials, the reaction solution 102 requires different precursors, additives, electrolytes, or a combination thereof. The detailed implementation is shown in Table 1 below, but the invention is not limited thereto.

Table 1         <TABLE border="1" borderColor="#000000" width="_0004"><TBODY><tr><td> Nanomaterial to be synthesized</td><td> Precursor</td><td> Additives</td><td> Electrolyte</td></tr><tr><td> Carbon Quantum Dots or Graphene Quantum Dots</td><td> Sodium Dodecyl Sulfate</td><td > </td><td> Hydrochloric acid</td></tr><tr><td> Cetyltrimethylammonium bromide</td><td> </td><td> Hydrochloric acid</td> </tr><tr><td> glucose</td><td> sodium hydroxide</td><td> sodium hydroxide</td></tr><tr><td> fructose</td> <td> Sodium hydroxide</td><td> Sodium hydroxide</td></tr><tr><td> Citric acid</td><td> Ethylenediamine</td><td> < /td></tr><tr><td> Citric acid</td><td> Dopamine</td><td> </td></tr><tr><td> Citric acid</td> <td> secondary butylamine</td><td> </td></tr><tr><td> glucose</td><td> ethylenediamine</td><td> </td> </tr><tr><td> glucose</td><td> secondary butylamine</td><td> </td></tr><tr><td> fructose</td><td > Ethylenediamine</td><td> </td></tr><tr><td> Fructose</td><td> Secondary butylamine</td><td> </td></ Tr><tr><td> sucrose</td><td> ethylenediamine</td><td> </td></tr> <tr><td> sucrose</td><td> secondary butylamine</td><td> </td></tr><tr><td> maltose</td><td> ethylenediamine </td><td> </td></tr><tr><td> maltose</td><td> secondary butylamine</td><td> </td></tr><tr ><td> Cadmium selenide quantum dots</td><td> Cadmium sulfate, sodium selenate</td><td> Potassium nitrilotriacetate</td><td> </td></tr ><tr><td> 矽 quantum dot</td><td> bismuth tetrachloride</td><td> </td><td> </td></tr><tr><td> four Barium bromide</td><td> </td><td> </td></tr><tr><td> cerium oxide</td><td> potassium chloride, lithium chloride Td><td> </td></tr><tr><td> lead selenide quantum dots</td><td> lead acetate, sodium selenate</td><td> nitrilotriacetic acid Potassium</td><td> </td></tr><tr><td> lead sulfide</td><td> lead dichloride, sulfur powder (using oleylamine as solvent) </td> <td> </td><td> </td></tr><tr><td> lead acetate</td><td> sodium lauryl sulfate, cetyltrimethylammonium bromide, B Diaminetetraacetic acid and thiourea</td><td> </td></tr></TBODY></TABLE>

Next, referring to FIG. 1, the plasma generating apparatus 200 is placed on the reaction solution 102. The plasma generating device 200 includes a first electrode 202, a second electrode 204, and a power supply 206. The power supply 206 is electrically connected to the first electrode 202 and the second electrode 204, respectively.

Thereafter, the first electrode 202 is immersed in the reaction solution 102. In an embodiment, the first electrode 202 may be, for example, a platinum electrode that is not easily chemically reacted with the reaction solution 102 to be corroded or worn.

As shown in FIG. 1, the second electrode 204 is, for example, a hollow tubular structure. The tubular structure may be externally connected to a gas cylinder (not shown) and an inert gas 208 is introduced into the tubular structure. Thereafter, a plasma 210 is formed in the liquid surface of the reaction solution 102 by applying a voltage. In an embodiment, the plasma 210 can be, for example, a normal piezoelectric slurry or a low pressure plasma. The inert gas 208 can be, for example, a gas such as argon or helium.

The power supply 206 can be used to provide a DC voltage that passes through the high power resistor R with a high voltage to stabilize the current flowing into the second electrode 204. Thereafter, the inert gas 208 passing through the second electrode 204 is ionized to form a highly reactive gas group composed of electrons, positive ions, living radicals, and neutral gas molecules, that is, the plasma 210. .

For the nanomaterial of the present embodiment, the operating conditions of the plasma generating apparatus 200 are as follows. The flow rate of the inert gas 208 can be, for example, 15 sccm to 150 sccm. The operating voltage can be, for example, from 500 volts to 3000 volts. The output current can be, for example, 1 mA to 100 mA. The treatment time can be, for example, from 1 minute to 5 hours. However, the invention is not limited thereto.

In addition, although the first electrode 202 illustrated in FIG. 1 is an anode; the second electrode 204 is a cathode. However, the invention is not limited thereto. In other embodiments, the first electrode 202 may be a cathode; and the second electrode 204 may be an anode.

It should be noted that in the plasma treatment, high-energy electrons, positive ions, active radicals, and neutral gas molecules in the plasma 210 may strike the liquid surface of the reaction solution 102 and generate hydrated electrons. Under the liquid surface of the reaction solution 102, the hydrated electrons are electrochemically or non-electrochemically reacted with the precursor to synthesize the precursor into a plurality of nanoparticles. In the present embodiment, the formation of the nanoparticles by the plasma treatment also causes the reaction solution 102 to carry a large amount of charged or charged particles. Therefore, the nanoparticles are not easily aggregated and can be more uniformly distributed in the reaction. In solution 102.

In one embodiment, the nanoparticle comprises a zero-dimensional nanomaterial, which may be, for example, a carbon quantum dot, a graphene quantum dot, a germanium quantum dot, a cadmium selenide quantum dot, a lead selenide quantum dot, a lead sulfide quantum. Point or a combination thereof. The nanoparticles may have a particle size between 1 nm and 100 nm. However, the invention is not limited thereto. In other embodiments, the nano particles may also form a one-dimensional, two-dimensional or three-dimensional nano material.

In summary, this embodiment has a simple and rapid synthesis step and a unique formation mechanism compared to other electrochemical systems. Compared with the conventional plasma, the plasma treatment of the present embodiment can have a higher electron density and energy per unit volume, so as to promote a faster and more diverse electrochemical reaction and non-electrochemical reaction under the liquid surface of the reaction solution.

In order to demonstrate the achievability of the present invention, a number of examples are given below to further illustrate the nanomaterial of the present invention. Although the following experiments are described, the materials used, the amounts and ratios thereof, the processing details, the processing flow, and the like can be appropriately changed without departing from the scope of the invention. Therefore, the invention should not be construed restrictively based on the experiments described below.

Instance 1 :preparation SDS Graphene quantum dots

First, 1 wt% of sodium dodecyl sulfate (SDS) and 0.000135 wt% of hydrochloric acid were added to a deionized water solvent to form a reaction solution. Next, the reaction solution was placed in a crystallizing dish. Thereafter, a plasma generating device is disposed on the reaction solution. Specifically, an anode electrode composed of metal platinum is immersed in the reaction solution. An argon gas having a flow rate of 25 sccm was introduced into the cathode electrode composed of a hollow tube. Thereafter, an operating voltage of about 1900 volts, an output current of 9.6 mA, and a treatment time of 3 hours were applied to the cathode electrode to ionize argon gas to form a plasma. The plasma bombards the liquid surface of the reaction solution and generates hydrated electrons, so that sodium dodecyl sulfate generates an electrochemical reaction or a non-electrochemical reaction to synthesize sodium lauryl sulfate into a plurality of graphene quantum dots, It is called SDS graphene quantum dots.

2 is a transmission electron microscope image of the graphene quantum dots of Example 1. 3 is a particle size distribution diagram of graphene quantum dots of Example 1.

As shown in FIG. 2, the SDS graphene quantum dots (that is, the black dots of FIG. 2) formed according to the procedure of Example 1 are uniformly distributed on the carbon film (that is, the region other than the black dots in FIG. 2), and are not aggregated. Together. After further dispersing the dispersed SDS graphene quantum dots, as shown in FIG. 3, the average particle diameter is 4.9 nm, which is in accordance with the size defined by the graphene quantum dots.

4 is a Raman spectrum of the graphene quantum dots of Example 1. 5 is a two-dimensional photoluminescence contour map of the graphene quantum dots of Example 1.

In the Raman spectrum of Fig. 4, the characteristic peaks of SDS graphene quantum dots fall near 1586.8 cm ^-1 and 1347.9 cm ^-1 , respectively. The former is called G-band, which is generated by the vibration of carbon molecules along the plane of graphite. Therefore, it can be regarded as the degree of graphitization of carbon materials. The latter is D-band, which is derived from structural defects or carbon material boundaries. The stronger the signal, the less complete the graphite structure. When the intensity of the G-band is greater than the intensity of the D-band, it indicates that the SDS graphene quantum dots have sp ² carbon molecular bonds and some structural defects. In addition, the weak 2D-band (ie, 2781.1 cm ^-1 ) indicates that the material structure of the SDS graphene quantum dots has crystalline characteristics.

In addition, from the two-dimensional photoluminescence contour map of FIG. 5, in the excitation wavelength range of 325 nm to 425 nm, the SDS graphene quantum dots have an emission wavelength of 400 nm to 520 nm, that is, visible blue light. The wavelength, that is, the SDS graphene quantum dots, emits blue light.

Instance 2 :preparation CA Graphene quantum dots

First, 10.6 wt% of citric acid (CA) and 0.0335 wt% of ethylenediamine were added to a deionized water solvent to form a reaction solution. Next, the reaction solution was placed in a crystallizing dish. A plasma generating device is disposed on the reaction solution. Specifically, an anode electrode composed of metal platinum is immersed in the reaction solution. An argon gas having a flow rate of 25 sccm was introduced into the cathode electrode composed of a hollow tube. Thereafter, an operating voltage of about 2000 volts, an output current of 9.6 mA, and a processing time of 1 hour were applied to the cathode electrode to ionize argon gas to form a plasma. The plasma bombards the liquid surface of the reaction solution and produces hydrated electrons, such that the citric acid produces an electrochemical reaction or a non-electrochemical reaction to synthesize citric acid into a plurality of graphene quantum dots, hereinafter referred to as CA graphene quantum dots.

6 is a fluorescence spectrum of the graphene quantum dots of Example 2.

From the fluorescence spectrum of Fig. 6, when the excitation wavelength is changed from 340 nm to 410 nm, the fluorescence emission wavelength of CA graphene quantum dots changes from 425 nm to 525 nm. That is, the CA graphene quantum dots will change from blue light to green light. In addition, the fluorescence intensity of CA graphene quantum dots at 525 nm is also higher than that at 425 nm. In detail, the CA graphene quantum dots formed in Example 2 have various particle size sizes, and therefore, as the excitation wavelength increases, the fluorescence emission wavelength of the CA graphene quantum dots also increases. From this, it is understood that the quantum dots synthesized by the present invention have multiple emission wavelengths. Therefore, the quantum dots synthesized by the present invention can be widely applied to different fields such as biomedicine, electronic components, and energy equipment.

In summary, the present invention treats a plurality of nanoparticles in a reaction solution by plasma treatment. This embodiment has the advantage of simple operation compared to other electrochemical systems. In addition, compared with the conventional plasma, the plasma treatment of the present invention can have a higher electron density and energy per unit volume, so as to promote a faster and more diverse electrochemical reaction and non-electrochemical reaction under the liquid surface of the reaction solution. . In addition, the bottom-up method can also control the particle size and surface characteristics of the nanomaterial, and then be applied to the sensing element. Moreover, the quantum dots synthesized by the present invention have multiple emission wavelengths. Therefore, the quantum dots synthesized by the present invention can be widely applied to different fields such as biomedicine, electronic components, and energy equipment.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention, and any one of ordinary skill in the art can make some changes and refinements without departing from the spirit and scope of the present invention. The scope of the invention is defined by the scope of the appended claims.

100‧‧‧Reaction device
102‧‧‧Reaction solution
200‧‧‧ Plasma generating device
202‧‧‧First electrode
204‧‧‧second electrode
206‧‧‧Power supply
208‧‧‧Inert gas
210‧‧‧ Plasma
R‧‧‧resistance

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic illustration of a reaction apparatus in accordance with one embodiment of the present invention. 2 is a transmission electron microscope (TEM) image of the graphene quantum dots of Example 1. 3 is a particle size distribution diagram of graphene quantum dots of Example 1. 4 is a Raman spectrum of the graphene quantum dots of Example 1. 5 is a two-dimensional photoluminescence contour map of the graphene quantum dots of Example 1. 6 is a fluorescence spectrum of the graphene quantum dots of Example 2.

100‧‧‧Reaction device

102‧‧‧Reaction solution

200‧‧‧ Plasma generating device

202‧‧‧First electrode

204‧‧‧second electrode

206‧‧‧Power supply

208‧‧‧Inert gas

210‧‧‧ Plasma

R‧‧‧resistance

Claims (9)

A method for producing a nano material, comprising: providing a reaction solution, wherein the reaction solution comprises at least a precursor; and performing a plasma treatment on the reaction solution to form a plurality of nano particles in the reaction solution, wherein The nano particles are uniformly distributed in the reaction solution, wherein the nano particles comprise carbon quantum dots, graphene quantum dots, germanium quantum dots, cadmium selenide quantum dots, lead selenide quantum dots, lead sulfide quantum dots or A combination thereof, wherein the plasma processing process parameters include a flow rate of the inert gas of 15 sccm to 150 sccm, an operating voltage of 500 volts to 3000 volts, an output current of 1 mA to 100 mA, and a treatment time of 1 minute to 5 hours. The method for producing a nanomaterial according to claim 1, wherein the precursor comprises a carbon-containing precursor, a ruthenium-containing precursor, a cadmium-containing precursor, a lead-containing precursor, and a sixth Family material precursors or combinations thereof. The method for producing a nanomaterial according to claim 2, wherein the carbonaceous precursor comprises sodium lauryl sulfate, cetyltrimethylammonium bromide, sodium dodecylbenzenesulfonate, and lemon. Acid, glucose, fructose, sucrose, maltose, polyethylene glycol or a combination thereof. The method for producing a nanomaterial according to claim 2, wherein the ruthenium-containing precursor comprises ruthenium tetrachloride, ruthenium tetrabromide, ruthenium dioxide or a combination thereof. The method for producing a nanomaterial according to claim 2, wherein the cadmium-containing precursor comprises cadmium sulfate, and the lead-containing precursor comprises lead acetate, lead dichloride or a combination thereof, the sixth group material The precursor includes sodium selenate, sulfur powder, or a combination thereof. A method for producing a nanomaterial according to claim 1, wherein The reaction solution further comprises an additive comprising ethylenediamine, secondary butylamine, phenylenediamine, dopamine, potassium nitrilotriacetate, potassium chloride, lithium chloride, sodium lauryl sulfate, bromine Cetyltrimethylammonium, ethylenediaminetetraacetic acid, thiourea, sodium hydroxide or a combination thereof. The method for producing a nanomaterial according to claim 1, wherein the reaction solution further comprises an electrolyte comprising hydrochloric acid, sodium hydroxide or a combination thereof. The method for producing a nano material according to claim 1, wherein the step of treating the plasma comprises: placing the reaction solution in a reaction device; and disposing a plasma generating device on the reaction solution, wherein The plasma generating device includes a first electrode, a second electrode, and a power supply, the power supply is electrically connected to the first electrode and the second electrode, respectively; the first electrode is immersed in the reaction solution; An inert gas is introduced into the second electrode, and the second electrode is disposed on the liquid surface of the reaction solution; and the power supply is turned on, so that the second electrode generates a plasma in the reaction solution to The precursor is synthesized into the nanoparticles. The method of producing a nanomaterial according to claim 8, wherein the first electrode comprises a platinum electrode.