Nano copper wire and method for preparing nano copper wire by electrodeposition method

Abstract

The present invention provides a nano copper wire and a method for preparing the nano copper wire by electrodeposition, and relates to the technical field of nano materials. The method comprises the following steps: mixing a copper salt solution and a directing agent adenine solution in a certain proportion, and adding sulfuric acid to adjust the pH. After mixing, the concentration of copper ions in the solution is 15-30 mmol / L, and the concentration of adenine is 2-4 mmol / L. A bright copper foil is used as a working electrode, a saturated calomel electrode is used as a reference electrode, and a platinum wire is used as a counter electrode. The electrochemical workstation is connected, and electrodeposition is performed under set voltage and deposition time conditions at room temperature to obtain nano copper wires with uniform size, dense distribution, length of 2-3 μm, and diameter of 120-130 nm. The nano copper wires prepared by the electrochemical deposition method of the present invention have good dispersibility and oxidation resistance, uniform particle size, and a fast and simple preparation process.

Description

Technical Field

[0001] The invention relates to the research field of nano material technology, and in particular to a method for preparing nano copper wires by electrodeposition. Background Art

[0002] As an important industrial raw material, nano copper can replace precious metals such as silver and gold, greatly reducing the cost in the preparation of conductive materials, high-efficiency catalysts, and lubricant additives. It has broad application prospects and can be used in catalysis, microelectronics, coatings, medicine, and other fields. Copper nanowires with high aspect ratios have excellent ductility and conductivity. Flexible copper nanowires with high transmittance and high conductivity can be made into transparent electrodes to replace expensive ITO conductive materials and are used in many fields such as touch screens, lithium-ion batteries, smart windows, and robotic systems.

[0003] The currently reported method for preparing copper nanowires mainly uses a reducing agent (hydrazine hydrate, potassium borohydride, sodium borohydride, glucose, thiourea dioxide, hydroxylamine hydrochloride, etc.) to reduce copper ions to obtain copper grains, and then adds a guiding agent (1,2-propylenediamine, methylamine, ethylenediamine, diethylenetriamine, etc.) to finally obtain nano copper wires (such as patents CN 110385444 B, CN103658675 B, CN 110355379 A). The whole process requires the use of a variety of reagents such as protective agents, dispersants, and guiding agents, involving explosive chemicals (hydrazine hydrate, sodium borohydride, etc.), toxic and volatile organic substances (such as ethylenediamine, diethylenetriamine, etc.), and excessive alkali solution (sodium hydroxide, potassium hydroxide, etc.). At the same time, it needs to be carried out under heating conditions, and the obtained nano copper wires need to be filtered and washed many times. The preparation process is cumbersome and time-consuming, and is not suitable for mass production. There are also reports that precious metals such as gold, silver and platinum are used as catalysts to prepare ultra-long nanowires, which are expensive to prepare. These preparation methods are costly and complex, and the synthesized nanowires have low uniformity and low yield. Therefore, it is still very important to provide a nano copper wire with uniform size, good dispersion and good oxidation resistance prepared by simple materials and simple methods. Summary of the invention

[0004] Based on this, the purpose of the present invention is to provide a method for obtaining nano copper wires with uniform size, good dispersibility and good oxidation resistance at room temperature. The whole process does not involve a variety of toxic and volatile reagents, only a single directing agent adenine needs to be added, and the production cost is low, the process is simple and the yield is high.

[0005] The present invention provides a method for preparing nano copper wires, which is characterized by comprising the following steps:

[0006] (1) Dissolve copper salt and directing agent adenine in water to prepare a solution, mix them in a certain proportion, and add sulfuric acid to adjust the pH to 1.03.

[0007] (2) placing the solution of step (1) in an electrolytic cell, using a bright copper foil as a working electrode, a saturated calomel electrode as a reference electrode, and a platinum wire as a counter electrode, connected to an electrochemical workstation, and performing an electrodeposition process at room temperature under set voltage and time parameters.

[0008] Wherein, the copper salt used in step (1) is CuSO4·5H2O, and the concentration of the copper salt is 15-30 mmol / L; the concentration of adenine used is 2-4 mmol / L.

[0009] The copper foil used in step (2) has a thickness of 70 μm and a size of 5×5 mm. 2 , the deposition was carried out using a CHI660E electrochemical workstation, the applied voltage was -0.3 to -0.4 V, and the deposition time was 200 to 400 s.

[0010] The nano copper wires prepared by the preparation method have good oxidation resistance, uniform particle size, and an aspect ratio of 16:1-23:1.

[0011] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0012] (1) The present invention prepares nano copper wires in an aqueous solution without the need for an organic solvent, and has low raw material costs, a simple and fast preparation process, and a high yield, which is conducive to industrial production.

[0013] (2) The copper nanowires obtained by the present invention have good dispersibility and oxidation resistance, and the particle size is relatively uniform. The length of the nano copper wires is 2 to 3 μm, and the diameter is between 120 and 130 nm. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a SEM image of the nano copper wire prepared in Example 1 of the present invention.

[0015] Figure 2 This is a SEM image of the nano copper wire prepared in Example 2 of the present invention.

[0016] Figure 3 This is the XRD diagram of the nano copper wire prepared in Example 2 of the present invention. DETAILED DESCRIPTION

[0017] The technical solution of the embodiment of the present invention is described in detail below in conjunction with the accompanying drawings in the embodiment of the present invention:

[0018] Example 1

[0019] (1) Weigh 0.5 g of copper sulfate (CuSO4·5H2O) and dissolve it in water. Add sulfuric acid to adjust the pH to 1.03.

[0020] (2) Take 50 mL of the above solution in an electrolytic cell and add a 70 μm thick, 5 × 5 mm 2 The copper foil was used as the working electrode, the saturated calomel electrode was used as the reference electrode, and the platinum wire was used as the counter electrode. They were connected to a CHI660E electrochemical workstation and electrochemical deposition was carried out at room temperature. The electrodeposition applied voltage was set to -0.38 V and the deposition time was 300 s.

[0021] (3) After the electrodeposition, the samples were cleaned with ultrapure water and dried by scanning electron microscopy (SEM). Figure 1 .

[0022] Example 2

[0023] (1) Weigh 0.5 g of copper sulfate (CuSO4·5H2O) and 0.054 g of adenine and dissolve them in water. Add 0.26 mL of sulfuric acid to adjust the pH to 1.03.

[0024] (2) Take 50 mL of the above solution in an electrolytic cell and add a 70 μm thick, 5 × 5 mm 2 The copper foil was used as the working electrode, the saturated calomel electrode was used as the reference electrode, and the platinum wire was used as the counter electrode, which was connected to a CHI660E electrochemical workstation for electrochemical deposition. The electrodeposition applied voltage was set to -0.38 V and the deposition time was 300 s.

[0025] (3) After the electrodeposition, the samples were washed with ultrapure water, dried, and subjected to scanning electron microscopy (SEM) characterization and X-ray diffraction analysis (XRD). Figure 2 and Figure 3 .

[0026] According to the SEM images of Example 1 and Example 2, when adenine is added according to the method of Example 2, nano copper wires with good dispersion and distinct particle sizes can be obtained.

[0027] The method for preparing nano copper wires by using the electrodeposition method provided by the present invention is simple and quick, and the prepared nano copper wires are uniform in size, well dispersed, and have good oxidation resistance.

Claims

1. A method for preparing nano copper wires by electrodeposition, characterized in that: include: (1) dissolving copper salt and directing agent adenine in water to prepare a solution, mixing them in a certain proportion, and adding sulfuric acid to adjust the pH to 1.03; (2) placing the solution of step (1) in an electrolytic cell, using a bright copper foil as a working electrode, a saturated calomel electrode as a reference electrode, and a platinum wire as a counter electrode, connected to an electrochemical workstation, and performing an electrodeposition process at room temperature under set voltage and time parameters.

2. The method for preparing nano copper wires by electrodeposition according to claim 1, characterized in that: The copper salt used in step (1) is CuSO4·5H2O. After mixing, the concentration of copper ions in the solution is 15-30 mmol / L, and the concentration of adenine is 2-4 mmol / L.

3. The method for preparing nano copper wires by electrodeposition according to claim 1, characterized in that: The copper foil used in step (2) has a thickness of 70 μm and a size of 5×5 mm. 2 The deposition was carried out at room temperature using a CHI660E electrochemical workstation, the applied voltage was -0.3 to -0.4 V, and the deposition time was 200 to 400 s.

4. The method for preparing nano copper wires by electrodeposition according to claim 1, characterized in that: The prepared nano copper wire has good oxidation resistance, uniform particle size, a length of 2 to 3 μm, and a diameter of 120 to 130 nm.

5. The nano copper wire prepared by the method for preparing nano copper wire by electrodeposition according to any one of claims 1 to 4, characterized in that the aspect ratio of the nano copper wire is 16:1-23:1.

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