A method for synthesizing high-aspect-ratio nanosilver wire in aqueous phase

Abstract

The application discloses a kind of high slenderness ratio nano silver wire aqueous phase synthesis method, comprising the following steps: one, fructose, sodium citrate, 1-butyl-1-methyl pyrrolidine chloride is dissolved in deionized water, obtain solution A;Two, silver nitrate is dissolved in deionized water, obtain solution B;Three, solution B is added to solution A, obtain mixed liquid C;Four, after mixed liquid C is heated and reacts, obtain silver wire mother liquor;Five, after silver wire mother liquor is handled, obtain nano silver wire.The application discloses a kind of high slenderness ratio nano silver wire aqueous phase synthesis method, the method has the advantages of easy precision control slenderness ratio, synthesis process is simple, high yield, green and environmental protection, the obtained nano silver wire has the characteristics that silver line surface is without residual macromolecule, slenderness ratio is uniform, especially the diameter of silver line can be accurately controlled, and the silver line diameter distribution range error is ±3nm, which is far from other aqueous phase synthesis method.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of nanometer metal conductive material production, and relates to a method for preparing nanometer silver wire with precisely controllable length-diameter ratio in aqueous phase. BACKGROUND

[0002] With the development of the times, various kinds of intelligent devices have been integrated into various fields and play an important role in various fields, so the manufacturing of intelligent devices has attracted more and more attention. Touch screen, as an input component of intelligent devices, is mainly composed of protective glass, conductive film, touch chip, optical adhesive and other components. At present, ITO conductive film with excellent conductivity and light transmission is the mainstream transparent conductive film material on the market, and the indium tin oxide (ITO) conductive film technology has matured, so ITO conductive film accounts for more than 90% of the market share of small-size touch screens. However, the disadvantages of ITO transparent conductive film are also obvious. First, In in ITO conductive film is a rare metal, which is expensive and has the problem of exhaustion. Second, the preparation process is complex. It is mainly prepared by deposition on PET substrate through magnetron sputtering process, etc. The obtained ITO conductive film has defects such as low yield of large-size product, large resistance and poor bending resistance, which greatly limits its application in large-size touch screens and flexible touch screens. Nanometer silver wire is a good material that takes into account electrical and optical properties. It is praised as one of the ideal materials that can surpass ITO film in the 21st century due to its good photoelectric properties. Nanometer silver wire has important applications in the fields of conductivity, catalysis, biomedicine, antibacterial and optics due to its high conductivity, high light transmittance, strong bending resistance and low production cost.

[0003] At present, the preparation methods of nanometer silver wire mainly include two types: physical synthesis method and chemical synthesis method. Template method and gas phase synthesis method belong to physical synthesis method, and polyol method and hydrothermal method belong to chemical synthesis method. In industry, polyol method is the most commonly used method for producing nanometer silver wire, which has the characteristics of simple process, easy control, high yield and simple equipment. However, polyol method also has some limitations that affect its subsequent development, such as high reaction temperature, difficulty in cleaning polyvinylpyrrolidone attached to the surface of silver wire, and difficulty in treating organic waste liquid.

[0004] Nanometer silver wire aqueous phase synthesis method is a new method for synthesizing nanometer silver wire in recent years, and it is a new trend for synthesizing nanometer silver wire in the future. Nanometer silver wire aqueous phase synthesis method has the advantages of mild reaction temperature, green environmental protection and no residual polymer on the surface of silver wire because it is synthesized in aqueous phase without using polyvinylpyrrolidone as a capping agent. However, nanometer silver wire aqueous phase synthesis method also has some disadvantages, such as inability to precisely control the length-diameter ratio of silver wire and low yield, which seriously affect its large-scale application. SUMMARY

[0005] In order to solve the above technical problems, the application provides a new method for synthesizing high aspect ratio nanosilver wire in water phase, which has the advantages of mild reaction temperature, green environmental protection, simple synthesis process, no residual polymer on the surface of silver wire, precise control of aspect ratio, high yield, etc.

[0006] The technical scheme adopted by the application is as follows: a method for synthesizing high aspect ratio nanosilver wire in water phase, which comprises the following steps:

[0007] (1) Weigh fructose, sodium citrate and 1-butyl-1-methylpyrrolidine chloride into deionized water, stir and dissolve to obtain solution A, and wait for use;

[0008] (2) Weigh silver nitrate into deionized water, stir and ultrasonically dissolve to obtain solution B, and wait for use;

[0009] (3) Slowly add solution B to solution A while stirring to obtain a milky white suspension mixture C, and wait for use;

[0010] (4) Take out the polytetrafluoroethylene liner in the hydrothermal synthesis kettle, slowly pour the mixture C into the liner, put the liner back into the hydrothermal synthesis kettle, and tighten the kettle cover;

[0011] (5) Place the hydrothermal synthesis kettle in an oil bath for heating to perform nanosilver wire synthesis reaction in water phase, and after a period of reaction, obtain silver wire mother liquor D;

[0012] (6) Centrifuge the silver wire mother liquor D with deionized water and ethanol to obtain nanosilver wire;

[0013] In steps 1 and 2, the preferred mass ratio of 1-butyl-1-methylpyrrolidine chloride, sodium citrate, fructose and silver nitrate is 1:(1-20):(2-20):(1-10);

[0014] In step 5, the preferred oil bath temperature is 80-120℃, and the preferred reaction time is 5-30 hours;

[0015] In step 6, the obtained silver wire has a diameter of 15-60nm and a length of 10-60μm.

[0016] The application provides a high-aspect-ratio nanosilver wire aqueous phase synthesis method, which uses fructose as a reducing agent, sodium citrate as a surfactant, and 1-butyl-1-methylpyrrolidine chloride as a nucleation control agent. The nanosilver wire can be synthesized in an aqueous phase at a lower synthesis temperature and a shorter reaction time. The method has the advantages of easy and accurate control of the aspect ratio, simple synthesis process, high yield, and environmental protection. The obtained nanosilver wire has the characteristics of no residual polymer on the surface of the silver wire and uniform aspect ratio, and in particular, the diameter of the silver wire can be accurately controlled, and the diameter distribution range error of the silver wire is ± 3 nm, which is far beyond the reach of other aqueous phase synthesis methods. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 It is a high-magnification transmission electron microscope image of the nanosilver wire prepared in the embodiment 1 of the application.

[0018] Figure 2 It is a low-magnification transmission electron microscope image of the nanosilver wire prepared in the embodiment 1 of the application.

[0019] Figure 3 It is a high-magnification transmission electron microscope image of the nanosilver wire prepared in the embodiment 2 of the application.

[0020] Figure 4 It is a low-magnification transmission electron microscope image of the nanosilver wire prepared in the embodiment 2 of the application.

[0021] Figure 5 It is a high-magnification transmission electron microscope image of the nanosilver wire prepared in the embodiment 3 of the application.

[0022] Figure 6 It is a low-magnification transmission electron microscope image of the nanosilver wire prepared in the embodiment 3 of the application. DETAILED DESCRIPTION

[0023] The embodiments of the application are described in detail in the face of the embodiments of the application, the embodiments are implemented on the premise of the technical scheme of the application, and detailed implementation modes and specific operation processes are given, but the protection scope of the application is not limited to the following embodiments.

[0024] Embodiment 1: The technical scheme adopted by the application is as follows: a high-aspect-ratio nanosilver wire aqueous phase synthesis method, which comprises the following steps:

[0025] (1) 0.6 g of fructose, 0.5 g of sodium citrate and 0.2 g of 1-butyl-1-methylpyrrolidine chloride are weighed and dissolved in 100 g of deionized water to obtain solution A, which is used after stirring and dissolving;

[0026] (2) 0.3 g of silver nitrate is weighed and dissolved in 10 g of deionized water to obtain solution B, which is used after stirring and ultrasonic dissolving;

[0027] (3) Slowly add solution B into solution A while stirring to obtain a milky white suspension mixture C, which is ready for use;

[0028] (4) Take out the polytetrafluoroethylene liner in the hydrothermal synthesis kettle, slowly pour the mixture C into the liner, and put the liner back into the hydrothermal synthesis kettle, and tighten the kettle cover;

[0029] (5) Place the hydrothermal synthesis kettle in an oil bath at a temperature of 100℃ for heating, and perform a nano silver wire aqueous phase synthesis reaction, which lasts for 10 hours to obtain a silver wire mother liquor D;

[0030] (6) Centrifuge the silver wire mother liquor D using deionized water and ethanol to obtain nano silver wires, which, as can be seen from the transmission electron microscope test, have a diameter of 20 nm and a length of 23 μm, as shown in Figure 1 、 2 .

[0031] Example 2: The technical solution adopted by the present application is: a high aspect ratio nano silver wire aqueous phase synthesis method, which comprises the following steps:

[0032] (1) Weigh 1 g of fructose, 0.5 g of sodium citrate, and 0.3 g of 1-butyl-1-methylpyrrolidine chloride into 100 g of deionized water, stir and dissolve to obtain solution A, which is ready for use;

[0033] (2) Weigh 0.8 g of silver nitrate into 10 g of deionized water, stir and ultrasonically dissolve to obtain solution B, which is ready for use;

[0034] (3) Slowly add solution B into solution A while stirring to obtain a milky white suspension mixture C, which is ready for use;

[0035] (4) Take out the polytetrafluoroethylene liner in the hydrothermal synthesis kettle, slowly pour the mixture C into the liner, and put the liner back into the hydrothermal synthesis kettle, and tighten the kettle cover;

[0036] (5) Place the hydrothermal synthesis kettle in an oil bath at a temperature of 90℃ for heating, and perform a nano silver wire aqueous phase synthesis reaction, which lasts for 20 hours to obtain a silver wire mother liquor D;

[0037] (6) Centrifuge the silver wire mother liquor D using deionized water and ethanol to obtain nano silver wires, which, as can be seen from the transmission electron microscope test, have a diameter of 40 nm and a length of 45 μm, as shown in Figure 3 、 4 .

[0038] Example 3: The technical solution adopted by the present application is: a high aspect ratio nano silver wire aqueous phase synthesis method, which comprises the following steps:

[0039] (1) 2 g of fructose, 1 g of sodium citrate, and 0.5 g of 1-butyl-1-methylpyrrolidine chloride were weighed into 100 g of deionized water, and after stirring and dissolving, solution A was obtained and was ready for use;

[0040] (2) 1.5 g of silver nitrate was dissolved in 10 g of deionized water, and after stirring and ultrasonic dissolution, solution B was obtained and was ready for use;

[0041] (3) Solution B was slowly added to solution A while stirring to obtain a milky white suspension mixture C, which was ready for use;

[0042] (4) The polytetrafluoroethylene liner in the hydrothermal synthesis kettle was taken out, the mixture C was slowly poured into the liner, the liner was put back into the hydrothermal synthesis kettle, and the kettle cover was tightly screwed;

[0043] (5) The hydrothermal synthesis kettle was placed in an oil bath at a temperature of 100°C for heating, and the nano-silver wire aqueous phase synthesis reaction was carried out for 25 hours to obtain silver wire mother liquor D;

[0044] (6) The silver wire mother liquor D was treated by centrifugation with deionized water and ethanol to obtain nano-silver wires. As can be seen from the transmission electron microscope test, the diameter of the obtained silver wires is 50 nm, and the length is 50 μm, as shown in FIGS. 1 and 2. Figure 5 6 ​​

Claims

1. A method for aqueous phase synthesis of high aspect ratio silver nanowires, characterized in that, The method comprises the following steps: (1) weigh sodium citrate, fructose and 1-butyl-1-methylpyrrolidine chloride, dissolve them in deionized water, stir and dissolve to obtain solution A, and wait for use; (2) weigh silver nitrate, dissolve it in deionized water, stir and ultrasonically dissolve to obtain solution B, and wait for use; (3) slowly add solution B to solution A while stirring to obtain a milky white suspension mixture C, and wait for use; (4) take out the polytetrafluoroethylene lining in the hydrothermal synthesis kettle, slowly pour the mixture C into the lining, put the lining back into the hydrothermal synthesis kettle, and tighten the kettle cover; (5) place the hydrothermal synthesis kettle in an oil bath to heat and perform the silver nanowire water-phase synthesis reaction, and after a period of reaction, obtain silver nanowire mother liquor D; (6) centrifuge the silver nanowire mother liquor D using deionized water and ethanol to obtain the silver nanowires.

2. The method according to claim 1, wherein the silver nanowires have a high aspect ratio. In step (1), the mass ratio of 1-butyl-1-methylpyrrolidine chloride to sodium citrate is 1:(1-20).

3. The method according to claim 1, wherein the silver nanowires have a high aspect ratio. In step (1), the mass ratio of 1-butyl-1-methylpyrrolidine chloride to fructose is 1:(2-20).

4. The method according to claim 1, wherein the silver nanowires have a high aspect ratio. In step (2), the mass ratio of 1-butyl-1-methylpyrrolidine chloride to silver nitrate is 1:(1-10).

5. The method according to claim 1, wherein the silver nanowires have a high aspect ratio. In step (5), the preferred oil bath temperature is 80-120℃.

6. The method according to claim 1, wherein the silver nanowires have a high aspect ratio. In step (5), the preferred reaction time is 5-30 hours.

Images