KR20120039105A - Method for producing silver nanoparticles - Google Patents

Abstract

PURPOSE: A manufacturing method of a silver nano-particle is provided to obtain a silver nano-particle which is physically and chemically stable and has a uniform particle size by using a specific organophosphorous compound as a stabilizer. CONSTITUTION: A manufacturing method of a silver nano-particle comprises next steps: preparing silver nitrate solution by throwing silver nitrate in deionized water; adding 20ml of the organophosphorous with same number of moles in 1ml of the silver nitrate solution as stabilizer and stirring; and adding 20-100 micro liter of hydrazine which includes 80% N2H3 to the silver nitrate solution and obtaining expanded silver after stirring 1 minute. The organophosphorous is one selected from Mono(2-ethylhexyl)-2-ethylhexylphosponate(PC88A), Bis(2-ethylhexyl)phosphate(BEHPa), and Bis(2-ethylhexyl)phosphite(BEHPi).

Description

Method for producing silver nanoparticles {Method for producing silver nanoparticles}

An object of the present invention relates to a manufacturing method of silver nanoparticles, in particular silver nanoparticles having a uniform size of less than 10nm, silver nanoparticles having a uniform particle size of several hundred nanosize, and the produced silver nanoparticles can be stored for a long time It is about how.

In recent years, as the development of industrial technology has been innovative, nanotechnology has also been developed, making it easy to manufacture a large number of inorganic particles or metal particles having a nano size. Due to the maximal surface area and quantum effects, nanoparticles of inorganic or metals have been reported not only to achieve better physical and chemical properties in bulk, but also to exhibit properties different from those in bulk. .

As such, the nanoparticles show almost the same or better effect than the material used in the bulk phase even when the microparticles are used in a small amount. Also, since the nanoparticles are used only in the small amount, they exhibit little toxicity to the human body and the environment. Recognized as a beneficial material for the environment, nanoparticles are spotlighted as a new material and a lot of research is being conducted.

When these nanoparticles are mixed into polymer products such as synthetic fibers, plastic molded products, films, paints, and inks to be used as composite materials, composite materials due to low compatibility, cohesion, and non-uniform distribution with polymers and inorganic or metal nanoparticles It is known that it is difficult to obtain an intended effect of nanoparticle formation by causing problems such as deterioration of physical properties and / or opacity of the compound. In order to solve such problems such as incompatibility, aggregation, non-uniform distribution, for example, functionalization of nanoparticles, use of compatibilizers such as dispersants, polymerization reaction in the presence of nanoparticles, etc. have been proposed, but still satisfactory solutions The method was not developed.

On the other hand, silver is a metal having the highest conductivity after gold, and it has been known for some time to have complex performances such as antibacterial, antiseptic, antifungal, deodorant, far infrared emission, and antistatic.

Silver is inexpensive compared to other precious metals, but is still an expensive precious metal for other materials. Therefore, silver is fine-grained or supported on porous materials such as silica and zeolite in order to economically use silver's conductivity, antibacterial and deodorizing properties. Or coated or plated.

Silver nanoparticles that have been micronized to nano size are expected to exhibit more excellent properties than silver in bulk, and there is a great deal of research on nanotechnology for preparing silver nanoparticles in powder or solution phase. On the other hand, in the study using the silver nanoparticles prepared in this way, silver nanoparticles show an antibacterial, bactericidal, antifungal effect, etc., which is extremely improved compared to the silver in the bulk, such as showing a germicidal power of 99% or more within a few seconds for any kind of bacteria. It was reported to show.

As a manufacturing method for preparing such silver nanoparticles, "Synthesis of Ag NP ₃ in a polyvinylalchol solution while irradiating microwaves, Ag NP synthesis of several nm size [R. Abargues, R. Gradess, J. Canet-Ferrer, K. Abderrafi, JL Valdes, J. Mart, New J. Chem. 33 (2009) 913 "and" Reduce AgNO ₃ using NaH and 2t-BuONa to synthesize Ag NPs of several nm size [L. Balan , J. -Synthesis of several nm size Ag NP ₃ by reducing AgNO ₃ using P. Malval, R, Schneider, D, Burget, Mater. Chem. Phys. 104 (2007) 417 "and" Lipopeptide biosurfactant, NaHB4 [ AS Reddy, C.-Y. Chen, SC Baker, C.-C. Chen, J.-S. Jean.C.-W.Fan, H.-R. Chen, J.-C. Wang, Mater. Lett. 63 (2009) 1227 "and Ag NP ₃ reduction using" poly (allylamine) as a reducing agent to reduce AgNO ₃ [R. Sardar, J.-W. Park, JS Shumaker-Parry , Langumuir 23 (2007) 11883 ". In addition, a manufacturing method for producing silver nanoparticles is also known through various patent documents.

However, the method for preparing silver nanoparticles presented in the above-described paper and other patent documents has a disadvantage in that it is difficult to make silver nanoparticles having a uniform particle size.

In addition, the silver nanoparticles prepared by the prior art have a disadvantage in that it is difficult to store for a long time because it is not chemically and physically stable.

Therefore, using the silver nanoparticle manufacturing method of the prior art, it is difficult to mass-produce stable silver nanoparticles, which makes it difficult to economically produce.

Accordingly, an object of the present invention is to provide a method for producing silver nanoparticles, which has a uniform particle size and is chemically and physically stable and can be stored for a long time, thereby allowing mass production and economic production of stable silver nanoparticles.

In order to achieve the object of the present invention, the method for producing silver nanoparticles according to the present invention uses silver nitrate (Silver Nitride, AgNO ₃ ) as a starting material, hydrazine (Hydrazine) as a reducing agent, and an organic phosphate compound as a stabilizer It is characterized by using.

The method for producing silver nanoparticles according to the present invention is characterized in that it is obtained by adding a stabilizer to a silver nitrate solution, stirring for 5 minutes, and then adding hydrazine to stir for 1 minute.

In the method for preparing silver nanoparticles according to the present invention, the organophosphate compound as the stabilizer is mono (2-ethylhexyl) -2-ethylhexylphosphonate (Mono (2-ethylhexyl) -2-ethylhexylphosponate, PC88A), bis ( 2-ethylhexyl) phosphate (Bis (2-ethylhexyl) phosphate, BEHPa), and bis (2-ethylhexyl) phosphite (Bis (2-ethylhexyl) phosphite, BEHPi) is characterized in that one selected.

When the silver nanoparticles are manufactured according to the silver nanoparticle manufacturing method according to the present invention, not only the silver nanoparticles of well-controlled particle size can be obtained, but also the silver nanoparticles which can be easily stored for a long period of time have the effect of increasing the mass productivity and economic efficiency of the silver nanoparticles. Will be.

1 is a TEM of silver nanoparticles obtained according to the change in the concentration of AgNO ₃ when using bis (2-ethylhexyl) phosphate (Bis (2-ethylhexyl) phosphate, BEHPa) as a stabilizer in the silver nanoparticles manufacturing method according to the present invention Drawings showing photos and particle distribution.
Figure 2 shows the AgNO ₃ when using mono (2-ethylhexyl) -2-ethylhexyl phosphonate (Mono (2-ethylhexyl) -2-ethylhexylphosponate, PC88A) as a stabilizer in the silver nanoparticles manufacturing method according to the present invention TEM picture and particle distribution diagram of the silver nanoparticles obtained according to the concentration change.
3 shows silver nanoparticles obtained from a concentration of AgNO ₃ of 0.50 M when bis (2-ethylhexyl) phosphite (Bis (2-ethylhexyl) phosphite, BEHPi) is used as a stabilizer in the silver nanoparticle manufacturing method according to the present invention. TEM photo drawing.

Hereinafter, the present invention will be described with reference to the accompanying drawings.

In the method for preparing silver nanoparticles according to the present invention, first, silver nitrate (AgNO ₃ ) is used as a starting material, and mono (2-ethylhexyl) -2-ethylhexylphosphonate (Mono (2-ethylhexyl) -2- is used as a stabilizer. one selected from ethylhexylphosponate (PC88A), bis (2-ethylhexyl) phosphate (Bis (2-ethylhexyl) phosphate, BEHPa), and bis (2-ethylhexyl) phosphite (Bis (2-ethylhexyl) phosphite, BEHPi) Organophosphate compounds are used. And hydrazine (N ₂ H ₃ , 80%) is used as the reducing agent.

Mono (2-ethylhexyl) -2-ethylhexylphosphonate (Mono (2-ethylhexyl) -2-ethylhexylphosponate, PC88A), bis (2-ethylhexyl) phosphate (Bis (2-ethylhexyl) phosphate, BEHPa) The molecular structure of bis (2-ethylhexyl) phosphite (BEHPi) is as follows.

(1) Mono (2-ethylhexyl) -2-ethylhexyl phosphonate (Mono (2-ethylhexyl) -2-ethylhexylphosponate, PC88A)

(2) bis (2-ethylhexyl) phosphate (Bis (2-ethylhexyl) phosphate, BEHPa)

(3) bis (2-ethylhexyl) phosphite (Bis (2-ethylhexyl) phosphite, BEHPi)

In the above, R represents 2-ethylhexyl.

The method for preparing silver nanoparticles using the starting materials, stabilizers, and reducing agents as described above is as follows.

First, silver nitrate is added to pure water to prepare a silver nitric acid solution of 0.5M, 0.25M, and 0.1M.

Then, 1 mL of each silver nitric acid solution is taken, and 20 mL of the same mole of organophosphoric acid is added to each of these silver nitric acid solutions. The organophosphoric acid is organophosphoric acid mixed in cyclohexane.

Then, after stirring for 5 minutes, the mixture was stirred again for 1 minute while dropping 20 μl to 100 μl dropwise. This results in diffused Ag (0) with a dark yellow color.

Examples performed in the present invention are as follows.

Example 1

As shown in Table 1, the same mole of bis (2-ethylhexyl) phosphate (Bis (2-ethylhexyl) phosphate, BEHPa) solution was added to each of 0.5M, 0.25M, and 0.1M silver nitric acid solutions. 19.0 µl, 47.0 µl and 95.0 µl of hydrazine were respectively added to the silver nitric acid solution to obtain diffused silver.

Experiment AgNO ₃ (M / mL) BEHPa (M / mL) Hydrazine (μl Experiment 1-1 0.10 / 1.0 0.0050 / 20 19.0 Experiment 1-2 0.25 / 1.0 0.0125 / 20 47.0 Experiment 1-3 0.50 / 1.0 0.0250 / 20 95.0

The TEM image and particle size distribution of the silver nanoparticles obtained by the above method are shown in FIG. 1.

FIG. 1 (a) shows TEM photographs and particle size distribution diagrams of silver nanoparticles when the concentration of silver nitric acid is 0.10M, and FIG. 1 (b) shows silver nanoparticles when the concentration of silver nitric acid is 0.25M. Figure 1 shows the TEM image and the particle size distribution, Figure 1 (c) shows the TEM image and particle size distribution of the silver nanoparticles when the silver nitric acid concentration is 0.50M.

As can be seen from the figure, when the concentration of silver nitric acid is 0.10M silver nanoparticles have a particle size in the range of 3 to 11nm, it can be seen that the distribution is concentrated over 4 to 10nm.

In addition, when the silver nitric acid concentration is 0.25M it can be seen that the silver nanoparticles have a particle size in the range of 2 to 10nm, the distribution is concentrated over 4 to 9nm.

In addition, when the silver nitric acid concentration is 0.50M silver nanoparticles have a particle size in the range of 3 to 9nm, it can be seen that the distribution is concentrated over the range of 5 to 8nm.

As can be seen above, when bis (2-ethylhexyl) phosphate (BEHPa) is used as a stabilizer, it can be seen that the particle distribution area becomes narrower as the concentration of silver nitric acid increases. have. That is, it can be seen that silver nanoparticles having a relatively uniform particle size of less than 10 nm can be obtained.

[Example 2]

As shown in Table 2, the same moles of mono (2-ethylhexyl) -2-ethylhexylphosphonate (Mono (2-ethylhexyl) -2-ethylhexylphosponate) in 0.5M, 0.25M, and 0.1M silver nitric acid solutions, respectively , PC88A) solution was added, and 19.0 μl, 47.0 μl, and 95.0 μl of hydrazine were added to each of the silver nitric acid solutions as reducing agents to obtain diffused silver.

Experiment AgNO ₃ (M / mL) PC88A (M / mL) Hydrazine (μl Experiment 2-1 0.10 / 1.0 0.0050 / 20 19.0 Experiment 2-2 0.25 / 1.0 0.0125 / 20 47.0 Experiment 2-3 0.50 / 1.0 0.0250 / 20 95.0

TEM image and particle size distribution of the silver nanoparticles obtained by the above method are shown in FIG. 2.

FIG. 2 (a) shows TEM photographs and particle size distribution diagrams of silver nanoparticles when the concentration of silver nitric acid is 0.10M, and FIG. 1 (b) shows silver nanoparticles when the concentration of silver nitric acid is 0.25M. Figure 1 shows the TEM image and the particle size distribution, Figure 1 (c) shows the TEM image and particle size distribution of the silver nanoparticles when the silver nitric acid concentration is 0.50M.

As can be seen from the figure, silver nanoparticles have a particle size in the range of 2 to 7 nm when the concentration of silver nitric acid is 0.10M, and the distribution map shows that about 45% of the particles have a particle size of 5 nm and about 35% of the particles. It can be seen that they have particles of 4 nm.

In addition, when the silver nitric acid concentration is 0.25M it can be seen that the silver nanoparticles have a particle size in the range of 3 to 11nm, the distribution is concentrated over 4 to 7nm.

In addition, when the silver nitric acid concentration is 0.50M it can be seen that the silver nanoparticles have a particle size in the range of 2 to 11nm, the distribution is concentrated over 3 to 8nm.

As can be seen from the above, in the case of using mono (2-ethylhexyl) -2-ethylhexyl phosphonate (PC88A) as a stabilizer, the concentration of silver nitric acid is It can be seen that the higher the particle distribution area becomes. That is, as the concentration of silver nitric acid is lower, it can be seen that silver nanoparticles having a relatively uniform particle size of less than 10 nm can be obtained.

Example 3

As shown in Table 3, the same mole of bis (2-ethylhexyl) phosphite (Bis (2-ethylhexyl) phosphite, BEHPi) solution was added to each 0.5 M silver nitric acid solution, and 95.0 μl of hydrazine was added to the silver nitric acid solution. Was added to obtain diffused silver.

Experiment AgNO ₃ (M / mL) BEHPi (M / mL) Hydrazine (μl Experiment 1 0.50 / 1.0 0.0250 / 20 95.0

The TEM image and particle size distribution of the silver nanoparticles obtained in the above method are shown in FIG. 3.

Unlike Examples 1 and 2, the size of the Ag particles is about 40 to 100 nm, which is very large, and the distribution is also very wide.

As can be seen from the above embodiments, bis (2-ethylhexyl) phosphite (Bis (2-ethylhexyl) phosphite, BEHPi) without OH group has a very large nanoparticle size and a wide distribution. That is, it can be seen that the size of the nanoparticles varies depending on the presence of OH groups.

In addition, although Ag particles of several nm are made in Examples 1 and 2, bis (2-ethylhexyl) phosphate (Bis (2-ethylhexyl) phosphate, BEHPa) has two ether groups, whereas mono Since (2-ethylhexyl) -2-ethylhexyl phosphonate (Mono (2-ethylhexyl) -2-ethylhexylphosponate, PC88A) has one ether group, due to the difference of substituted ether groups, In Example 1 and Example 2 there is a difference in the nanoparticle size and distribution. In other words, as the concentration of silver nitrate increases, the width of the bis (2-ethylhexyl) phosphate (BEHPa) becomes narrower, whereas mono (2-ethylhexyl) -2-ethylhexylphosphate In the case of fonate (Mono (2-ethylhexyl) -2-ethylhexylphosponate, PC88A), the distribution becomes wider.

In terms of particle size, bis (2-ethylhexyl) phosphate (BEHPa) is not significantly affected by the concentration of silver nitrate, but mono (2-ethylhexyl) -2-ethylhexylphosphonate (Mono (2-ethylhexyl) -2-ethylhexylphosponate, PC88A) increases the particle size with increasing concentration.

Bis (2-ethylhexyl) phosphate (Bis (2-ethylhexyl) phosphate, BEHPa) and mono (2-ethylhexyl) -2-ethylhexyl in terms of particle size in consideration of particle size (4-7 nm) and distribution Phosphonate (Mono (2-ethylhexyl) -2-ethylhexylphosponate, PC88A) is very effective as a stabilizer.

Bis (2-ethylhexyl) phosphite (BEHPi) is effective as a stabilizer when preparing silver nanoparticles having a particle size of several tens to several hundred nm.

Therefore, it can be seen that the stabilizers used through the three embodiments described above have excellent silver nanoparticle generation ability compared with the prior art.

Claims (7)

Preparing silver nitrate solution by adding silver nitrate to pure water;
20 ml of the same molar number of organophosphoric acid compound as a stabilizer was added to 1 mL of the silver nitric acid solution, followed by stirring for 5 minutes,
Method of producing a silver nano-particles, characterized in that the stabilizer is added to the silver nitrate solution is added to 20 to 100μl hydrazine containing 80% N ₂ H ₃ and stirred for 1 minute to obtain a diffused silver. The organophosphate compound is mono (2-ethylhexyl) -2-ethylhexylphosphonate (Mono (2-ethylhexyl) -2-ethylhexylphosponate, PC88A), bis (2-ethylhexyl) phosphate (Bis (2-ethylhexyl) A method for producing silver nanoparticles, characterized in that one selected from the group consisting of phosphate, BEHPa, and bis (2-ethylhexyl) phosphite (Bis (2-ethylhexyl) phosphite, BEHPi). The method of claim 2, wherein the concentration of the silver nitric acid solution is 0.10, 0.25 and 0.50M, respectively, wherein the selected organophosphate compound is bis (2-ethylhexyl) phosphate (BEHPa), When the injected hydrazine is 19.0, 47.0 and 95 µl, respectively, the size of the obtained silver nanoparticles is in the range of 2 to 11 nm, and the size distribution region of the obtained silver nanoparticles becomes narrower as the concentration of the silver nitric acid solution increases. Silver nanoparticles manufacturing method. The method of claim 2,
The method of claim 2, wherein the concentration of the silver nitric acid solution is 0.10, 0.25 and 0.50M, respectively, and the selected organophosphate compound is mono (2-ethylhexyl) -2-ethylhexylphosphonate (Mono (2-ethylhexyl). ) -2-ethylhexylphosponate (PC88A), and the injected hydrazine is 19.0, 47.0, and 95 µl, respectively, and the obtained silver nanoparticles range in size from 2 to 11 nm, and the silver nanoparticles obtained as the concentration of the silver nitric acid solution increases. Silver nanoparticles manufacturing method characterized in that the size distribution area of the wider. The concentration of the silver nitric acid solution is 0.5M, the organophosphorus compound is bis (2-ethylhexyl) phosphite (Bis (2-ethylhexyl) phosphite, BEHPi), 95.0 μl of hydrazine added When, the nano-particle size of the nano-particles manufacturing method, characterized in that 40 to 100nm. The method of manufacturing silver nanoparticles according to any one of claims 2 to 5, wherein an OH group is present in the organophosphate compound to reduce the size of the silver nanoparticles. The silver nanoparticle according to any one of claims 2 to 5, wherein the larger the number of ether groups in the organophosphate compound is, the narrower the size distribution of the silver nanoparticles is, and the smaller the number of ether groups increases the size of the silver nanoparticles. Particle preparation method.

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