A method for preparing copper nanowires using template-free electrodeposition

Abstract

This invention provides a method for preparing copper nanowires using template-free electrodeposition, relating to the technical field of micro / nano synthesis. The method includes: mixing and stirring Janus Green, an electrolyte, a buffer, and water to obtain an electrolyte; polarizing the electrolyte and then adding a copper salt to obtain a copper salt-containing electrolyte; placing a copper foil in the copper salt-containing electrolyte for electrodeposition, thereby depositing copper nanowires on the surface of the copper foil. This invention solves the problems of inconsistent morphology, low yield, and difficulty in obtaining large quantities of one-dimensional copper nanowires in the preparation process. The prepared copper nanowires are one-dimensional nanomaterials with ideal aspect ratios and uniform and stable morphology.

Description

Technical Field

[0001] This invention relates to the field of micro / nano synthesis technology, and in particular to a method for preparing copper nanowires using template-free electrodeposition. Background Technology

[0002] Copper nanowires, with their excellent conductivity and flexibility, have been applied in fields such as field emission displays, transparent conductive films, and wearable electronic devices. Although copper is popular in the market due to its low cost, the price of copper-based nanowires is not low; 1 g of copper nanowires with an aspect ratio of 300 or higher generally costs over 7000 yuan. The main reason is the difficulty in mass-producing copper nanowires; therefore, the low-cost synthesis of large quantities of high aspect ratio copper nanowires is a goal pursued by many researchers.

[0003] Thermochemical synthesis often requires the addition of environmentally harmful reagents such as long-chain alkylamines, so how to obtain large quantities of nanowires using environmentally friendly methods has become our research goal.

[0004] Based on the green research concept, we are trying to prepare nanowires without templates in electrochemistry. However, the preparation of nanowires without templates in electrochemical processes faces the problem of difficulty in controlling the morphology. This difficulty in controlling the morphology leads to uneven deposition, making it difficult for electrodeposition technology to obtain large quantities of nanomaterials.

[0005] The paper "Hierarchical Copper with Inherent Hydrophobicity Mitigates ElectrodeFlooding for High-Rate CO2 Electroreduction to Multicarbon Products" discloses a method for obtaining copper nanoneedles by controlling the current. Although this method produces copper dendrites similar to one-dimensional materials, it suffers from excessive primary and secondary branches and an aspect ratio of less than 10, which prevents it from being classified as a nanowire. Only when the aspect ratio is greater than 10 can it be defined as a nanowire. I find this method particularly despicable, as it cannot obtain a large number of one-dimensional copper nanostructures.

[0006] Therefore, there is an urgent need to develop a method for obtaining large quantities of one-dimensional nanomaterials and stably acquiring the morphology of copper nanowires through template-free electrodeposition technology.

[0007] In view of this, the present invention is hereby proposed. Summary of the Invention

[0008] The purpose of this invention is to provide a method for preparing copper nanowires using template-free electrodeposition. This method solves the problems encountered in the preparation of copper nanowires, such as inconsistent morphology, low yield, and difficulty in obtaining large quantities of one-dimensional copper nanomaterials.

[0009] In order to achieve the above-mentioned objectives of the present invention, the following technical solution is adopted: In a first aspect, the present invention provides a method for preparing copper nanowires using template-free electrodeposition, the method comprising: The electrolyte is obtained by mixing and stirring the Janus Green, electrolyte, buffer and water. The electrolyte is polarized and then copper salt is added to obtain an electrolyte containing copper salt. Copper foil is placed in the copper salt-containing electrolyte for electrodeposition, and copper nanowires are deposited on the surface of the copper foil.

[0010] Furthermore, the electrolyte comprises, by mass concentration: 0.1~0.5 g / L Janus Green, 0.1~0.5 g / L electrolyte, 10~20 g / L buffer, and water as solvent.

[0011] Furthermore, the electrolyte is selected from any one or a combination of at least two of sodium chloride, potassium chloride, sodium hypochlorite, or potassium hypochlorite.

[0012] Furthermore, the electrolyte is selected from sodium chloride.

[0013] Furthermore, the buffer is selected from any one or a combination of at least two of boric acid, aminotris(hydroxymethane), citrate buffer, carbonate buffer, or barbiturate buffer.

[0014] Furthermore, the buffer is boric acid.

[0015] Furthermore, the mixing speed is 500~600 rpm, and the mixing time is 20~40 min.

[0016] Furthermore, the polarization treatment specifically involves using carbon paper as a working electrode to perform constant potential polarization on the electrolyte.

[0017] Furthermore, the polarization treatment potential is -3 to -1.5 V, and the polarization treatment time is 4 to 6 hours.

[0018] Furthermore, the copper salt is selected from any one or a combination of at least two of copper sulfate, copper chloride, copper nitrate, copper formate, or copper acetate.

[0019] Furthermore, the copper salt is copper sulfate.

[0020] Further, the mass ratio of the phenazine green, electrolyte, buffer and copper salt is (1~3):(25~35):(85~95):(180~195).

[0021] Furthermore, the concentration of copper salt in the copper-containing electrolyte is 35~39 g / L.

[0022] Furthermore, the electrodeposition specifically involves using a copper foil as a working electrode to perform constant potential polarization on the copper salt-containing electrolyte, thereby depositing copper nanowires on the surface of the copper foil.

[0023] Furthermore, the electrodeposition is performed using a three-electrode system, wherein the working electrode is a copper foil, the counter electrode is a platinum electrode, and the reference electrode is a calomel electrode.

[0024] Furthermore, the electrodeposition potential is -3 to -1 V, and the electrodeposition time is 100 to 150 s.

[0025] Furthermore, the copper foil requires the following pretreatment steps before electrodeposition: The copper foil was immersed in a mixed solution of isopropanol and formic acid to obtain the pretreated copper foil.

[0026] Furthermore, the volume ratio of isopropanol to formic acid is (50~100):(3~6).

[0027] Furthermore, the soaking temperature is 20~30℃, and the soaking time is 0.5~2 h.

[0028] Furthermore, after the electrodeposition is completed, the following post-processing steps are required: The copper nanowires formed on the surface of the copper foil are washed, and then the copper nanowires on the surface of the copper foil are removed and stored in an organic solvent.

[0029] Furthermore, the washing solvent is water and / or ethanol.

[0030] Furthermore, the organic solvent used for storage is n-hexane.

[0031] In a second aspect, the present invention provides a copper nanowire prepared by the method for preparing copper nanowires using template-free electrodeposition as described in the first aspect.

[0032] Furthermore, the copper nanowires are one-dimensional nanomaterials.

[0033] Furthermore, the aspect ratio of the copper nanowire is 30 to 70.

[0034] Furthermore, the length of the copper nanowire is 30~80 μm; the diameter of the copper nanowire is 850~950 nm.

[0035] Compared with the prior art, the present invention has the following beneficial effects: (1) The method of the present invention adds Janus Green to the electrolyte and polarizes the electrolyte so that the decomposition products of JGB can control the electrodeposition growth of copper nanowires. The prepared copper nanowires are one-dimensional nanomaterials with ideal aspect ratio and uniform and stable morphology. (2) The method described in this invention has the characteristics of simple preparation conditions, strong operability, mild conditions and good repeatability, and can realize the large-scale mass preparation of one-dimensional nanomaterial copper nanowires; (3) The raw material cost of copper nanowires obtained by electrodeposition is extremely low, and the electrolyte can be continuously utilized when combined with electrodeposition equipment, thereby achieving the effect of no pollution to the environment. Attached Figure Description

[0036] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0037] Figure 1 A physical diagram of the electrodeposition equipment provided by the present invention.

[0038] Figure 2 This is a morphology diagram of the copper nanowires prepared in Example 1 of the present invention. Detailed Implementation

[0039] Unless otherwise defined herein, the scientific and technical terms used in conjunction with this invention shall have the meanings commonly understood by one of ordinary skill in the art. The meaning and scope of terms shall be clear; however, in any case of potential ambiguity, the definitions provided herein shall prevail over any dictionary or foreign definitions. In this application, unless otherwise stated, the use of "or" means "and / or". Furthermore, the use of the term "comprising" and other forms is non-limiting.

[0040] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0041] In a first aspect, the present invention provides a method for preparing copper nanowires using template-free electrodeposition, the method comprising: The electrolyte is obtained by mixing and stirring the Janus Green, electrolyte, buffer and water. The electrolyte is polarized and then copper salt is added to obtain an electrolyte containing copper salt. Copper foil is placed in the copper salt-containing electrolyte for electrodeposition, and copper nanowires are deposited on the surface of the copper foil.

[0042] In this invention, the method for preparing copper nanowires by template-free electrodeposition involves adding Janus Green (JGB) to the electrolyte and polarizing the electrolyte to obtain the decomposition products of JGB. The decomposition products of JGB (methyl violet 3RAX, N,N-dimethyl-p-phenylenediamine) achieve the control effect on the electrodeposition growth of copper nanowires. The prepared copper nanowires are one-dimensional nanomaterials with ideal aspect ratio and uniform and stable morphology.

[0043] As an optional implementation, the electrolyte comprises, by mass concentration: 0.1~0.5 g / L Janus Green, 0.1~0.5 g / L electrolyte, 10~20 g / L buffer, and water as solvent.

[0044] As an optional implementation, the concentration of Janus Green (JGB) in the electrolyte is 0.1~0.5 g / L, for example, it can be 0.1 g / L, 0.15 g / L, 0.2 g / L, 0.25 g / L, 0.3 g / L, 0.35 g / L, 0.4 g / L, 0.45 g / L, 0.5 g / L, etc.

[0045] As an optional implementation, the concentration of the electrolyte in the electrolyte solution is 0.1~0.5 g / L, for example, it can be 0.1 g / L, 0.15 g / L, 0.2 g / L, 0.25 g / L, 0.3 g / L, 0.35 g / L, 0.4 g / L, 0.45 g / L, 0.5 g / L, etc.

[0046] As an optional implementation, the concentration of the buffer in the electrolyte is 10~20 g / L, for example, it can be 10 g / L, 11 g / L, 12 g / L, 13 g / L, 14 g / L, 15 g / L, 16 g / L, 17 g / L, 18 g / L, 19 g / L, 20 g / L, etc.

[0047] As an optional implementation, the water is deionized water.

[0048] As an optional implementation, the electrolyte is selected from any one or a combination of at least two of sodium chloride, potassium chloride, sodium hypochlorite, or potassium hypochlorite.

[0049] In a preferred embodiment, the electrolyte is selected from sodium chloride.

[0050] As an optional implementation, the buffer is selected from any one or a combination of at least two of boric acid, aminotris(hydroxymethane), citrate buffer, carbonate buffer, or barbiturate buffer.

[0051] In a preferred embodiment, the buffer is boric acid.

[0052] As an optional implementation, the mixing speed is 500~600 rpm, for example, 500 rpm, 520 rpm, 540 rpm, 550 rpm, 560 rpm, 580 rpm, 600 rpm, etc., and the mixing time is 20~40 min, for example, 20 min, 25 min, 30 min, 35 min, 40 min, etc.

[0053] As an optional implementation, the polarization treatment specifically involves using carbon paper as a working electrode to perform constant potential polarization on the electrolyte.

[0054] As an optional implementation, the polarization treatment specifically involves using carbon paper as the working electrode, a platinum electrode as the counter electrode, and a calomel electrode as the reference electrode to perform constant potential polarization on the electrolyte.

[0055] As an optional implementation, the polarization treatment potential is -3 to -1.5 V, for example, it can be -3 V, -2.8 V, -2.6 V, -2.5 V, -2.4 V, -2.2 V, -2 V, 1.8 V, 1.6 V, 1.5 V, etc., and the polarization treatment time is 4 to 6 hours, for example, it can be 4 hours, 4.2 hours, 4.4 hours, 4.5 hours, 4.6 hours, 4.8 hours, 5 hours, 5.2 hours, 5.4 hours, 5.6 hours, 5.8 hours, 6 hours, etc.

[0056] As an optional implementation, the copper salt is selected from any one or a combination of at least two of copper sulfate, copper chloride, copper nitrate, copper formate, or copper acetate.

[0057] In a preferred embodiment, the copper salt is copper sulfate.

[0058] As an optional implementation, the molar ratio of Janus Green, electrolyte, buffer and copper salt is (1~3):(25~35):(85~95):(180~195).

[0059] As an optional implementation, the concentration of copper salt in the copper-containing electrolyte is 35~39 g / L, for example, it can be 35 g / L, 36 g / L, 37 g / L, 38 g / L, 39 g / L, etc.

[0060] As an optional implementation, the electrodeposition specifically involves using a copper foil as a working electrode to perform constant potential polarization on the copper salt-containing electrolyte, thereby depositing copper nanowires on the surface of the copper foil.

[0061] As an optional implementation, the electrodeposition is performed using a three-electrode system, wherein the working electrode of the three-electrode system is a copper foil, the counter electrode is a platinum electrode, and the reference electrode is a calomel electrode.

[0062] As an optional implementation, the electrodeposition potential is -3 to -1 V, for example, it can be -3 V, -2.8 V, -2.6 V, -2.5 V, -2.4 V, -2.2 V, -2 V, -1.8 V, -1.6 V, -1.5 V, -1.4 V, -1.2 V, -1 V, etc., and the electrodeposition time is 100 to 150 s, for example, it can be 100 s, 105 s, 110 s, 115 s, 120 s, 125 s, 130 s, 135 s, 140 s, 145 s, 150 s, etc.

[0063] As an optional implementation, the copper foil needs to undergo the following pretreatment steps before electrodeposition: The copper foil was immersed in a mixed solution of isopropanol and formic acid to obtain the pretreated copper foil.

[0064] As an optional implementation, the volume ratio of isopropanol to formic acid is (50~100):(3~6); Among them, "50~100" can be, for example, 50, 60, 70, 80, 90, 100, etc.; Among them, "3~6" can be, for example, 3, 3.5, 4, 4.5, 5, 5.5, 6, etc.

[0065] As an optional implementation, the soaking temperature is 20~30℃, for example, it can be 20℃, 22℃, 24℃, 26℃, 28℃, 30℃, etc., and the soaking time is 0.5~2 h, for example, it can be 0.5 h, 0.6 h, 0.8 h, 1 h, 1.2 h, 1.4 h, 1.5 h, 1.6 h, 1.8 h, 2 h, etc.

[0066] As an optional implementation, the following post-processing steps are required after electrodeposition: The copper nanowires formed on the surface of the copper foil are washed, and then the copper nanowires on the surface of the copper foil are removed and stored in an organic solvent.

[0067] As an optional implementation, the washing solvent is water and / or ethanol.

[0068] As an optional implementation, the organic solvent for storage is n-hexane.

[0069] In a second aspect, the present invention provides a copper nanowire prepared by the method for preparing copper nanowires using template-free electrodeposition as described in the first aspect.

[0070] As an optional implementation, the copper nanowires are one-dimensional nanomaterials.

[0071] As an optional implementation, the aspect ratio of the copper nanowire is 30 to 70, for example, it can be 30, 35, 40, 45, 50, 55, 60, 65, 70, etc.

[0072] As an optional implementation, the length of the copper nanowire is 30~80 μm, for example, it can be 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm, 60 μm, 65 μm, 70 μm, 75 μm, 80 μm, etc.

[0073] As an optional implementation, the diameter of the copper nanowire is 850~950 nm, for example, it can be 850 nm, 860 nm, 870 nm, 880 nm, 890 nm, 900 nm, 910 nm, 920 nm, 930 nm, 940 nm, 950 nm, etc.

[0074] The present invention will be further illustrated by the following examples. Unless otherwise specified, the materials in the examples are prepared according to existing methods or purchased directly from the market.

[0075] The following embodiments provide physical diagrams of the electrodeposition equipment. Figure 1 As shown.

[0076] Example 1 This embodiment provides a method for preparing copper nanowires using template-free electrodeposition, the method comprising: (1) Preparation of electrolyte: 0.00005 mol of Janus Green, 0.004 mol of NaCl, and 0.015 mol of boric acid were added to 50 mL of deionized water and stirred vigorously at 500 rpm for 30 min to obtain the electrolyte. The electrolyte, by mass concentration, comprises: 0.3 g / L Janus Green, 4.67 g / L NaCl, and 18.4 g / L boric acid, with deionized water as the solvent.

[0077] (2) Electrolyte pretreatment: Using carbon paper as the working electrode, a platinum electrode as the counter electrode, and a calomel electrode as the reference electrode, the electrolyte obtained in step (1) was potentiostatically polarized at a potential of -2.5 V for 5 h. After potentiostatic polarization, 0.0125 mol CuSO4 was added to obtain the electrolyte containing copper sulfate. The electrolyte, by mass concentration, includes: 6 g / mL of the decomposition products of Janus Green (methyl violet 3RAX, N,N-dimethyl-p-phenylenediamine), 0.3 g / L of NaCl, 18.4 g / L of boric acid, 39.8 g / L of CuSO4, and deionized water as the solvent.

[0078] (3) Pretreatment of copper foil: Cut the copper foil into 1×3 cm pieces. 2 A rectangular piece of copper foil of a certain size was immersed in a mixed solution of isopropanol and formic acid (where V isopropanol:V formic acid = 50:3) for 1 h to obtain the pretreated copper foil.

[0079] (4) Electrodeposition preparation of copper nanowires: Using a three-electrode electrolytic cell, the working electrode is the copper foil pretreated in step (3), the counter electrode is a platinum electrode, and the reference electrode is a calomel electrode. The electrode is subjected to constant potential polarization at -2 V for 120 s. After polarization, the copper foil is removed from the electrode clamp and rinsed three times with deionized water and alcohol. The copper nanowires on the copper foil are then removed with a scraper and stored in n-hexane to obtain copper nanowires (e.g., ...). Figure 2 (As shown).

[0080] Example 2 This embodiment provides a method for preparing copper nanowires using template-free electrodeposition, the method comprising: (1) Preparation of electrolyte: 0.00005 mol of Janus Green, 0.004 mol of KCl, and 0.015 mol of boric acid were added to 50 mL of deionized water and stirred vigorously at 500 rpm for 40 min to obtain the electrolyte. The electrolyte, by mass concentration, comprises: 0.6 g / L Janus Green, 5.96 g / L KCl, and 18.4 g / L boric acid, and the solvent is deionized water.

[0081] (2) Electrolyte pretreatment: Using carbon paper as the working electrode, a platinum electrode as the counter electrode, and a calomel electrode as the reference electrode, the electrolyte obtained in step (1) was potentiostatically polarized at a potential of -2 V for 4 h. After potentiostatic polarization, 0.125 mol CuSO4 was added to obtain the electrolyte containing copper sulfate. The electrolyte, by mass concentration, includes: 6 g / mL of the decomposition products of Janus Green (methyl violet 3RAX, N,N-dimethyl-p-phenylenediamine), 0.3 g / L of KCl, 18.4 g / L of boric acid, 39.8 g / L of CuSO4, and deionized water as the solvent.

[0082] (3) Pretreatment of copper foil: Cut the copper foil into 1×3 cm pieces. 2 A rectangular piece of copper foil of the specified size was immersed in a mixed solution of isopropanol and formic acid (where V isopropanol:V formic acid = 5:3) for 4 hours to obtain the pretreated copper foil.

[0083] (4) Electrodeposition preparation of copper nanowires: Using a three-electrode electrolytic cell, the working electrode is the copper foil pretreated in step (3), the counter electrode is a platinum electrode, and the reference electrode is a calomel electrode. The electrode is constant potential polarized at -2 V for 120 s. After polarization, the copper foil on the electrode clamp is removed, and the electrode is rinsed three times with deionized water and alcohol. The copper nanowires on the copper foil are removed with a scraper and stored in n-hexane to obtain copper nanowires.

[0084] Example 3 This embodiment provides a method for preparing copper nanowires using template-free electrodeposition, the method comprising: (1) Preparation of electrolyte: 0.00005 mol of Janus Green, 0.004 mol of NaClO, and 0.015 mmol of boric acid were added to 50 mL of deionized water and stirred vigorously at 500 rpm for 40 min to obtain the electrolyte. The electrolyte, by mass concentration, comprises: 0.6 g / L Janus Green, 6 g / L NaClO, and 18.4 g / L boric acid, and the solvent is deionized water.

[0085] (2) Electrolyte pretreatment: Using carbon paper as the working electrode, a platinum electrode as the counter electrode, and a calomel electrode as the reference electrode, the electrolyte obtained in step (1) was potentiostatically polarized at a potential of -2 V for 6 h. After potentiostatic polarization, 0.125 mol CuSO4 was added to obtain the electrolyte containing copper sulfate. The electrolyte, by mass concentration, includes: 0.6 g / L of the decomposition products of Janus Green (methyl violet 3RAX, N,N-dimethyl-p-phenylenediamine), 6 g / L of NaClO, 18.4 g / L of boric acid, 39.8 g / L of CuSO4, and deionized water as the solvent.

[0086] (3) Pretreatment of copper foil: Cut the copper foil into 1×3 cm pieces. 2 A rectangular piece of copper foil of a certain size was immersed in a mixed solution of isopropanol and formic acid (where V isopropanol:V formic acid = 50:3) for 2 hours to obtain the pretreated copper foil.

[0087] (4) Electrodeposition preparation of copper nanowires: Using a three-electrode electrolytic cell, the working electrode is the copper foil pretreated in step (3), the counter electrode is a platinum electrode, and the reference electrode is a calomel electrode. The electrode is constant potential polarized at -2 V for 120 s. After polarization, the copper foil on the electrode clamp is removed, and the electrode is rinsed three times with deionized water and alcohol. The copper nanowires on the copper foil are removed with a scraper and stored in n-hexane to obtain copper nanowires.

[0088] Example 4 This embodiment provides a method for preparing copper nanowires using template-free electrodeposition. The only difference from Embodiment 1 is that in step (2), the nanowires are subjected to constant potential polarization at a potential of -1.5 V for 6.5 h. The other steps are the same as in Embodiment 1.

[0089] Example 5 This embodiment provides a method for preparing copper nanowires using template-free electrodeposition. The only difference from Embodiment 1 is that in step (2), the potential is constant for 3.5 h at a potential of -3.5 V. The other steps are the same as in Embodiment 1.

[0090] Example 6 This embodiment provides a method for preparing copper nanowires using template-free electrodeposition. The only difference from Example 1 is that in step (4), the nanowires are subjected to constant potential polarization at a potential of -0.5 V for 5 min. The other steps are the same as in Example 1.

[0091] Example 7 This embodiment provides a method for preparing copper nanowires using template-free electrodeposition. The only difference from Embodiment 1 is that in step (4), the potential is constant for 60 s at a potential of -3 V. The other steps are the same as in Embodiment 1.

[0092] Comparative Example 1 This comparative example provides a method for preparing copper nanowires. The only difference from Example 1 is that Janus Green is no longer added in step (1), and constant potential polarization is no longer performed in step (2). Instead, CuSO4 of the corresponding concentration is added directly. The other steps are the same as in Example 1.

[0093] Comparative Example 2 This comparative example provides a method for preparing copper nanowires. The only difference from Example 1 is that step (2) no longer involves constant potential polarization, but instead directly adds CuSO4 of the corresponding concentration. The other steps are the same as in Example 1.

[0094] Test case Test samples: Copper nanowires prepared in Examples 1-7, and copper nanowires prepared in Comparative Examples 1 or 2; Test method: (1) In the captured SEM images, using the software's ruler and measurement tools, the length value of each measured nanowire is divided by its diameter value to obtain a single aspect ratio. Finally, the average aspect ratio of all calculated aspect ratios is obtained to get the average aspect ratio of this batch of nanowires.

[0095] (2) After removing the copper nanowires from the copper foil with a scraper, dry them, weigh the mass of the copper nanowires, and calculate the final yield of copper nanowires based on the amount of copper salt added.

[0096] The specific test results are shown in Table 1 below; where " / " represents the absence of copper nanowires, resulting in irregular nanoparticles: Table 1

[0097] As shown in Table 1, the method of the present invention, by adding Janus Green to the electrolyte and polarizing the electrolyte, enables the decomposition products of JGB to control the electrodeposition growth of copper nanowires. The prepared copper nanowires are one-dimensional nanomaterials with ideal aspect ratio and uniform and stable morphology. Furthermore, the method of the present invention has the characteristics of simple preparation conditions, strong operability, mild conditions, and good reproducibility, and can realize the large-scale mass production of one-dimensional copper nanomaterials.

[0098] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing copper nanowires using template-free electrodeposition, characterized in that, The method includes: The electrolyte is obtained by mixing and stirring the Janus Green, electrolyte, buffer and water. The electrolyte is polarized and then copper salt is added to obtain an electrolyte containing copper salt. Copper foil is placed in the copper salt-containing electrolyte for electrodeposition, and copper nanowires are deposited on the surface of the copper foil.

2. The method for preparing copper nanowires by template-free electrodeposition according to claim 1, characterized in that, The electrolyte, by mass concentration, comprises: Janus Green 0.1~0.5 g / L, electrolyte 0.1~0.5 g / L, buffer 10~20 g / L, and water as the solvent; Preferably, the electrolyte is selected from any one or a combination of at least two of sodium chloride, potassium chloride, sodium hypochlorite, or potassium hypochlorite, and is preferably sodium chloride; Preferably, the buffer is selected from any one or a combination of at least two of boric acid, aminotris(hydroxymethane), citrate buffer, carbonate buffer or barbiturate buffer, and is preferably boric acid; Preferably, the mixing speed is 500~600 rpm, and the mixing time is 20~40 min.

3. The method for preparing copper nanowires using template-free electrodeposition according to claim 1, characterized in that, The polarization treatment specifically involves using carbon paper as the working electrode, a platinum electrode as the counter electrode, and a calomel electrode as the reference electrode to perform constant potential polarization on the electrolyte. Preferably, the polarization treatment potential is -3 to -1.5 V, and the polarization treatment time is 4 to 6 hours.

4. The method for preparing copper nanowires using template-free electrodeposition according to claim 1, characterized in that, The copper salt is selected from any one or a combination of at least two of copper sulfate, copper chloride, copper nitrate, copper formate, or copper acetate, preferably copper sulfate; Preferably, the concentration of copper salt in the copper-containing electrolyte is 35~39 g / L.

5. The method for preparing copper nanowires using template-free electrodeposition according to claim 1, characterized in that, The electrodeposition specifically involves using a copper foil as a working electrode to perform constant potential polarization on the copper salt-containing electrolyte, thereby depositing copper nanowires on the surface of the copper foil. Preferably, the electrodeposition is performed using a three-electrode system, wherein the working electrode of the three-electrode system is a copper foil, the counter electrode is a platinum electrode, and the reference electrode is a calomel electrode; Preferably, the electrodeposition potential is -3 to -1 V, and the electrodeposition time is 100 to 150 s.

6. The method for preparing copper nanowires by template-free electrodeposition according to claim 1, characterized in that, The copper foil requires the following pretreatment steps before electrodeposition: The copper foil was immersed in a mixed solution of isopropanol and formic acid to obtain the pretreated copper foil. Preferably, the volume ratio of isopropanol to formic acid is (50~100):(3~6); Preferably, the soaking temperature is 20~30℃ and the soaking time is 0.5~2 h.

7. The method for preparing copper nanowires by template-free electrodeposition according to claim 1, characterized in that, After electrodeposition, the following post-processing steps are required: The copper nanowires formed on the surface of the copper foil are washed, and then the copper nanowires on the surface of the copper foil are removed and stored in an organic solvent. Preferably, the washing solvent is water and / or ethanol; Preferably, the organic solvent for storage is n-hexane.

8. A copper nanowire, characterized in that, The copper nanowires are prepared by the method of template-free electrodeposition as described in any one of claims 1 to 7.

9. The copper nanowire according to claim 8, characterized in that, The copper nanowires are one-dimensional nanomaterials.

10. The copper nanowire according to claim 8 or 9, characterized in that, The aspect ratio of the copper nanowires is 30~70; Preferably, the length of the copper nanowire is 30~80 μm; the diameter of the copper nanowire is 850~950 nm.

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