A method for green and efficient electrocatalytic hydrogen atom transfer electrochemical synthesis of olefins in water

Abstract

The present application relates to a kind of green efficient electrocatalysis hydrogen atom transfer electrochemical synthesis olefin method, which uses cheap chemical alkynol, water as raw material, uses Pd TpBpy-SH with large specific surface area as electrocatalyst, uses electric energy as energy source, promotes water splitting hydrogen atom transfer to alkynol synthesis olefin compound, with atom economy, step simplicity, efficient, green and environmentally friendly synthesis route, to adapt to the requirement of industrial application, the synthesis method of the present application is more green, environment-friendly and wide application range.

Description

TECHNICAL FIELD

[0001] The present application relates to a method for electrochemical synthesis of olefins by transferring hydrogen atoms in water with green and efficient electrocatalysis, belonging to the technical field of electrochemical heterogeneous catalysis. BACKGROUND

[0002] Olefins, as a key basic chemical raw material in the petrochemical industry, have a wide range of downstream applications and play an important role in the synthesis of fine chemicals, advanced materials, drugs and fragrances. Therefore, the demand for olefins is increasing year by year. The chemical selective semi-hydrogenation of alkynes is one of the important reactions for the synthesis of olefins. In the past decade, numerous innovative catalytic methods have been developed to solve the problem of selective hydrogenation of alkynes.

[0003] Traditional thermal catalytic selective hydrogenation of alkynes has been widely used in the fields of petrochemical industry and fine chemical industry. However, different alkynes require different reaction conditions and catalysts. Most thermal catalytic hydrogenation of alkynes requires a reaction temperature range of 45-250℃, and an excess amount of H2 as a hydrogen source, and is carried out under suitable pressure for selective hydrogenation. H2 is a flammable gas, and its transportation and safety during the reaction process have caused people's concern. In addition, in this type of reaction, over-hydrogenation often occurs, generating alkane by-products, resulting in poor selectivity for target olefins; at the same time, the cracking of alkynes and intermediates to generate coke is also one of the side reactions of thermal catalytic hydrogenation. These problems not only reduce the selectivity of target olefins, but also produce oligomers and coke and other substances that have a serious impact on actual production, therefore, it is urgent to develop a catalyst that can effectively inhibit the semi-hydrogenation side reaction of alkynes and a safe, efficient and green semi-hydrogenation method of alkynes.

[0004] Electrochemical semi-hydrogenation of alkynes uses active hydrogen generated in situ from water, providing a safe, sustainable and environmentally friendly alternative to traditional hydrogenation processes. The earliest electrochemical hydrogenation of alkynes dates back to 1943, but at that time, due to low reaction current density, poor selectivity of olefins and low conversion rate of alkynes, it could not be compared with traditional thermal catalytic hydrogenation of alkynes, limiting the development of electrocatalytic hydrogenation of alkynes.

[0005] In recent years, with the rapid development of material synthesis technology and reaction devices, electrocatalytic hydrogenation of alkynes has returned to the public eye. Compared with traditional thermal catalytic hydrogenation, electrocatalytic hydrogenation of alkynes has the following advantages: first, electrochemical hydrogenation can be carried out at room temperature and pressure, reducing energy consumption and improving the stability of the hydrogenation process; second, the driving force of electrocatalysis comes from green renewable electricity, which can also alleviate the problem of waste wind power; third, water is used as a hydrogen source, avoiding the problems of hydrogen storage and excessive hydrogen consumption, and reducing the safety hazards in production.

[0006] Pd-based catalysts are the first choice for alkyne hydrogenation due to their high atom utilization, isolated and uniform active sites, and excellent ability to adsorb and store active hydrogen. However, the activity of Pd catalysts is often too high, leading to excessive catalytic reaction and the production of alkane by-products. Therefore, the electronic state of Pd in the palladium-based catalyst needs to be carefully designed to enhance activity and selectivity. A typical example is the Lindlar catalyst, which uses CaCO3 as a carrier and adds several modifiers (usually lead acetate) to inhibit excessive hydrogenation. This strategy to enhance selectivity comes at the cost of activity and introduces toxic substances, which can easily cause pollution. Therefore, in addition to the metal catalytic center, it is still crucial to select a suitable catalytic carrier, which can fix metal nanoparticles and change their dispersion ability and electronic effect. It is well known that covalent organic frameworks (COF) are a new type of porous crystalline organic catalytic carrier material. Due to their many advantages, such as suitable surface area, regular porosity, structural uniformity, and design ability, they show considerable potential applications in catalysis. Various researchers have developed many strategies to anchor metal nanoparticles on COF materials, which have excellent activity in catalytic reactions.

[0007] However, the study of metal-modified COF materials in the field of electrocatalytic hydrogenation reactions is still relatively scarce. Given the growing market demand for olefins and related high-value chemicals, it is urgent to develop more environmentally friendly and sustainable new electrochemical catalytic hydrogenation reactions. SUMMARY

[0008] In view of the deficiencies of the prior art, especially the problems of the existing catalytic system such as complex reaction system and operation, narrow application range, serious over-hydrogenation, and environmental unfriendliness, the present application provides a green and efficient electrocatalytic hydrogen atom transfer method for electrochemical synthesis of olefins in water. SUMMARY:

[0010] The method of the present application uses cheap chemicals alkyne and water as raw materials, uses Pd TpBpy-SH as an electrocatalyst, and uses electrical energy as an energy source to promote water splitting and produce active hydrogen for the synthesis of olefins from alkyne. The method has the advantages of atom economy, simple steps, low price, high efficiency, and green and environmentally friendly synthesis route to meet the requirements of industrial applications. The synthesis method of the present application is more green, environmentally friendly, and widely applicable. DETAILED DESCRIPTION

[0012] The present application is realized by the following technical solutions:

[0013] The application discloses a green and efficient method for electrochemical synthesis of olefins by transferring hydrogen atoms in water, which uses Pd TpBpy-SH as an electrocatalyst and electrical energy as an energy source to promote water splitting and produce active hydrogen to transfer to acetylene to synthesize olefins.

[0014] The solvent, electrolyte, acetylene, negative electrode, positive electrode and reference electrode are sequentially added into an electrolytic cell separated by a Nafion117 anion membrane, and the reaction is carried out under stirring at room temperature and under constant voltage, wherein the negative electrode is carbon paper loaded with Pd TpBpy-SH electrocatalyst, the positive electrode is a platinum sheet, and the reference electrode is a mercury / mercury oxide electrode.

[0015] According to the application, the carbon paper loaded with Pd TpBpy-SH electrocatalyst is prepared by the following method:

[0016] (1) tri-aldehyde-based resorcinol and 5,5'-diamino-2,2'-bipyridine are dissolved in a mixed solvent of N,N-dimethylacetamide and 1,2-dichlorobenzene, acetic acid solution is added, ultrasonic dispersion is carried out, freeze-thaw circulation is carried out, oven heating reaction is carried out, washing, filtration and drying are carried out, and grinding is carried out to obtain TpBpy COF catalyst;

[0017] (2) the TpBpy COF catalyst and palladium acetate are dispersed in dichloromethane, stirring is carried out under nitrogen atmosphere, filtration is carried out, and vacuum drying is carried out to obtain Pd-TpBpy COF loaded with metal palladium; then the Pd-TpBpy COF loaded with metal palladium and beta-mercaptoethylamine are dissolved in a mixed solvent of anhydrous ethanol and water, stirring, filtration, vacuum drying and grinding are carried out to obtain Pd TpBpy-SH catalyst;

[0018] (3) the Pd TpBpy-SH catalyst, conductive carbon black and polyvinylidene fluoride binder are dispersed in N-methylpyrrolidone, are uniformly mixed, and are coated on carbon fiber paper to obtain carbon paper loaded with Pd TpBpy-SH electrocatalyst.

[0019] According to the application, in step (1), the molar ratio of tri-aldehyde-based resorcinol to 5,5'-diamino-2,2'-bipyridine is (1-3):(2-5).

[0020] Most preferably, in step (1), the molar ratio of tri-aldehyde-based resorcinol to 5,5'-diamino-2,2'-bipyridine is 2:3.

[0021] According to the application, in step (1), the volume ratio of N,N-dimethylacetamide to 1,2-dichlorobenzene is (2-6):1.

[0022] Most preferably, in step (1), the volume ratio of N,N-dimethylacetamide to 1,2-dichlorobenzene is 3:1.

[0023] According to the application, preferably, in step (1), the mass-volume ratio of the tri-aldehyde phloroglucinol and the mixed solvent is (18-25):(1-5), unit, mg / mL.

[0024] According to the application, preferably, in step (1), the concentration of the acetic acid solution is 4-8M, and the volume ratio of the acetic acid solution to the mixed solvent is (0.1-0.5):(1-5).

[0025] According to the application, preferably, in step (1), the heating reaction temperature is 110-140℃, and the reaction time is 3-5 days.

[0026] According to the application, preferably, in step (2), the mass ratio of TpBpy COF to palladium acetate is (0.8-1):1.

[0027] According to the application, preferably, in step (2), the mass-volume ratio of palladium acetate to dichloromethane is (2-3):1, unit mg / mL.

[0028] According to the application, preferably, in step (2), the mass ratio of Pd TpBpy COF loaded with palladium metal to β-mercaptoethylamine is (40-60):(180-200).

[0029] According to the application, preferably, in step (2), the molar ratio of β-mercaptoethylamine to palladium acetate is (8-12):1.

[0030] Most preferably, in step (2), the molar ratio of β-mercaptoethylamine to palladium acetate is 10:1.

[0031] According to the application, preferably, in step (2), the volume ratio of anhydrous ethanol to water is (2-6):1.

[0032] According to the application, preferably, in step (2), the mass-volume ratio of β-mercaptoethylamine to the mixed solvent is (180-200):(8-20), unit, mg / mL.

[0033] According to the application, preferably, in step (3), the mass ratio of Pd TpBpy-SH electrocatalyst, conductive carbon black, and polyvinylidene fluoride binder is (4-10):(1-3):(1-3).

[0034] According to the application, preferably, in step (3), the mass-volume ratio of Pd TpBpy-SH electrocatalyst to azomethylnitrone is (1-2):(80-100), unit mg / μL.

[0035] Preferably, in the method for synthesizing an olefin compound:

[0036] According to the application, preferably, the electrolyte is potassium hydroxide, the solvent is a mixture of organic solvent and water, and the organic solvent is 1,4-dioxane.

[0037] According to the application, preferably, the volume ratio of dioxane to water is (4-6):(6-4) mL.

[0038] According to the application, preferably, the solvent, electrolyte and alkyne are mixed uniformly to form a mixture, and the concentration of the electrolyte in the mixture is 0.3-0.6 M.

[0039] According to the application, preferably, the solvent, electrolyte and alkyne are mixed uniformly to form a mixture, and the concentration of the alkyne in the mixture is 8-12 mM.

[0040] The application uses water as raw material and Pd TpBpy-SH as electrocatalyst, and water provides hydrogen source, when water is activated and decomposed on Pd TpBpy-SH to form hydrogen-containing intermediate, the intermediate selectively hydrogenates alkyne to olefin compound as active species, and the yield of the olefin compound is high, and too large or too small water content will result in reduced yield.

[0041] According to the application, preferably, the alkyne is 4-biphenylacetylene, and the structure is shown in the following formula I.

[0042]

[0043] According to the application, preferably, the reaction temperature is 20-30℃, and the reaction time is 8-12 hours.

[0044] According to the application, preferably, the applied voltage is 1.1-1.4 V.

[0045] According to the application, preferably, the reaction is carried out in air environment.

[0046] The application uses cheap chemicals alkyne and water as raw materials, uses Pd TpBpy-SH as electrocatalyst, and uses electric energy as energy source to promote water splitting, and the generated hydrogen atom is transferred to alkyne to synthesize olefin compound, and the obtained olefin structure is shown in formula II.

[0047]

[0048] The reaction route of the application is as follows:

[0049]

[0050] The technical features and advantages of the application are as follows:

[0051] 1. The method of the present invention uses inexpensive chemicals alkynes and water as raw materials, uses PdTpBpy-SH with an easily designed structure as an electrocatalyst, and uses electricity as an energy source to promote water cracking. The oxygen atoms generated are transferred to alkynes to synthesize olefin compounds. It has a highly efficient, green and environmentally friendly synthetic route with atom economy, simple steps, and low price, so as to meet the requirements of industrial applications. The synthetic method of the present invention is more green, environmentally friendly and has a wide range of applications.

[0052] 2. This invention employs an electrochemical method for synthesizing olefin compounds. This method avoids the use of toxic and harmful modifiers such as lead acetate and quinoline, as well as hazardous chemicals such as flammable hydrogen gas. It will not cause safety issues or hazardous waste residue problems. The method is simple to operate, has a considerable yield, is environmentally friendly, and has good application prospects.

[0053] 3. This invention uses water as a raw material and PdTpBpy-SH as an electrocatalyst. Water provides the hydrogen source. When water is activated and decomposed on PdTpBpy-SH, it forms a hydrogen-containing intermediate. This intermediate, as an active species, selectively hydrogenates alkynes to olefin compounds, resulting in a high olefin yield. This not only avoids the use of combustible hydrogen gas, greatly reducing reaction costs, but also has the advantages of simple and safe operation. It saves costs and avoids environmental pollution caused by lead-containing waste. Attached Figure Description

[0054] Figure 1 This is a SEM image of the Pd TpBpy-SH electrocatalyst prepared in Example 1 of this invention.

[0055] Figure 2 This is a TEM image of the Pd TpBpy-SH electrocatalyst prepared in Example 1 of the present invention.

[0056] Figure 3 The image shows the FT-IR spectrum of the Pd TpBpy-SH electrocatalyst prepared in Example 1 of this invention.

[0057] Figure 4 This is a TEM mapping image of the Pd TpBpy-SH electrocatalyst prepared in Example 1 of the present invention.

[0058] Figure 5 The standard curve used for the residual quantification of the substrate in this invention.

[0059] Figure 6 The standard curve used to quantify the product of this invention.

[0060] Figure 7 The standard curve used for quantifying the byproducts generated in this invention

[0061] Figure 8 This is a mass spectrum of the substrate, product, and byproduct of this invention. DETAILED DESCRIPTION

[0062] The present application will be further described in the following non-limiting examples.

[0063] The raw materials used in the examples can be commercially available or prepared according to the prior art.

[0064] Example 1:

[0065] The preparation method of Pd TpBpy-SH electrocatalyst is as follows:

[0066] (1) 21 mg of triformylphloroglucinol and 27.9 mg of 5,5'-diamino-2,2'-bipyridine were added to a Schlenk tube, followed by 1.5 mL of DMAc and 0.5 mL of o-DCB, and then 0.2 mL of 6M acetic acid was added and uniformly dispersed by ultrasonic. After three cycles of freezing-thawing-releasing under liquid nitrogen, it was sealed and placed in an oven at 120°C for 72h. After natural cooling to room temperature, it was extracted with DMAc, H2O and acetone, and dried at 60°C under vacuum to obtain TpBpy COF.

[0067] (2) 50 mg of TpBpy COF and 56 mg of palladium acetate were dispersed in 28 mL of dichloromethane and stirred for 6h under a nitrogen atmosphere, filtered and washed, and dried at 60°C under vacuum to obtain Pd TpBpy COF loaded with metal palladium. 50 mg of Pd TpBpy COF and 193 mg of β-mercaptoethylamine were dissolved in a mixture of anhydrous ethanol (6 mL) and water (2 mL), stirred at 30°C for 6h, filtered and washed, dried under vacuum, and ground to obtain Pd TpBpy-SH catalyst;

[0068] The SEM and TEM images of the Pd TpBpy-SH catalyst prepared in this example are shown in Figure 1 、 Figure 2 As can be seen from the SEM image, the prepared sample has a rod-like structure. The TEM image shows that the metal palladium is uniformly dispersed.

[0069] The infrared spectrum and TEM Mapping of the Pd TpBpy-SH catalyst prepared in this example are shown in Figure 3 、 Figure 4 The infrared spectrum shows the presence of C-N bond of the catalyst, indicating the successful synthesis of the catalyst framework. The TEM Mapping shows that the various elements of the catalyst are uniformly dispersed and the sulfur is successfully coordinated, further proving the successful synthesis of the catalyst.

[0070] Example 2:

[0071] Preparation of carbon paper loaded with Pd TpBpy-SH electrocatalyst:

[0072] Pd TpBpy-SH catalyst 5 mg, conductive carbon black, and a polydisperse difluoroethylene binder were dispersed in 500 μL of N-methylpyrrolidone at a mass ratio of 5:1:1, mixed uniformly to obtain a slurry, and the slurry was coated on a carbon fiber paper to obtain a carbon paper loaded with the Pd TpBpy-SH electrocatalyst after drying.

[0073] Example 3:

[0074] Electrocatalytic hydrogenation of alkyne:

[0075] In separate cells separated by a Nafion 117 ion membrane, 5 mL of dioxane, 5 mL of 1 M aqueous potassium hydroxide, and 0.1 mmol of 4-biphenylstyrene were sequentially added, a carbon paper loaded with the Pd TpBpy-SH electrocatalyst prepared in Example 2 was used as the anode, and a platinum sheet electrode was used as the cathode. The reaction was carried out under air at 25°C at a constant voltage of 1.1 V for 12 h, water was used as the raw material, water was split, and the oxygen atoms generated were transferred to the alkyne to synthesize an olefin compound.

[0076] Comparative Example 1

[0077] The electrocatalytic hydrogenation of alkyne was carried out according to the method described in Example 3, except that:

[0078] The water content was reduced to 4 mL, the volume ratio of water:dioxane was 4:6, and the other conditions were unchanged, and the reaction was carried out according to Example 3.

[0079] Comparative Example 2

[0080] The electrocatalytic hydrogenation of alkyne was carried out according to the method described in Example 3, except that:

[0081] The water content was increased to 6 mL, the volume ratio of water:dioxane was 6:4, and the other conditions were unchanged, and the reaction was carried out according to Example 3.

[0082] Comparative Example 3

[0083] The electrocatalytic hydrogenation of alkyne was carried out according to the method described in Example 3, except that:

[0084] A carbon fiber paper was used as the working electrode, and the other conditions were unchanged, and the reaction was carried out according to Example 3.

[0085] Comparative Example 4

[0086] The electrocatalytic hydrogenation of alkyne was carried out according to the method described in Example 3, except that:

[0087] A carbon paper loaded with TpBpy COF was used as the working electrode, and the other conditions were unchanged, and the reaction was carried out according to Example 3.

[0088] Comparative Example 5

[0089] The electrocatalytic hydrogenation of alkyne reaction method described in Example 3, except that:

[0090] The carbon paper loaded with Pd TpBpy COF was used as the working electrode, and other conditions were unchanged, and Example 3 was carried out.

[0091] Comparative Example 6

[0092] The electrocatalytic hydrogenation of alkyne reaction method described in Example 3, except that:

[0093] The carbon paper was used as the working electrode, and 5 mg of palladium acetate was added, and other conditions were unchanged, and Example 3 was carried out.

[0094] Comparative Example 7

[0095] The electrocatalytic hydrogenation of alkyne reaction method described in Example 3, except that:

[0096] The voltage was -0.9 V, and other conditions were unchanged, and Example 3 was carried out.

[0097] Comparative Example 8

[0098] The electrocatalytic hydrogenation of alkyne reaction method described in Example 3, except that:

[0099] The voltage was -1.0 V, and other conditions were unchanged, and Example 3 was carried out.

[0100] Comparative Example 9

[0101] The electrocatalytic hydrogenation of alkyne reaction method described in Example 3, except that:

[0102] The voltage was -1.2 V, and other conditions were unchanged, and Example 3 was carried out.

[0103] Comparative Example 10

[0104] The electrocatalytic hydrogenation of alkyne reaction method described in Example 3, except that:

[0105] The voltage was -1.3 V, and other conditions were unchanged, and Example 3 was carried out.

[0106] Comparative Example 11

[0107] The electrocatalytic hydrogenation of alkyne reaction method described in Example 3, except that:

[0108] The cathode was replaced with carbon paper loaded with Pd TpBpy-thiol, and other conditions were unchanged, and Example 3 was carried out.

[0109] The preparation of Pd TpBpy-thiol loaded carbon paper was carried out according to Example 2, and Pd TpBpy-SH catalyst was replaced by Pd-TpBpy-thiol, Pd TpBpy-thiol was prepared according to Example 1, except that β-mercaptoethylamine was replaced by propanethiol, and other parameters were unchanged.

[0110] Test example

[0111] The conversion rate and selectivity of Test Example 3 and Comparative Examples 1-11 are shown in Table 1 below:

[0112] Table 1

[0113]

[0114] As can be seen from the above Table 1, the water content, the type of cathode electrode and the electrochemical reaction voltage all affect the conversion rate and selectivity of the product, too high or too low water content will reduce the conversion rate of the substrate, changing the type of cathode electrode will lead to a decrease in yield or no reaction, and too low or too high voltage will lead to a decrease in conversion rate or selectivity. In summary, by controlling the water content, the type of cathode electrode and the electrochemical reaction voltage, and using Pd TpBpy-SH with large specific surface area as an electrocatalyst, the present application uses electrical energy as the energy source to promote water splitting, and the generated hydrogen atoms are transferred to alkyne to synthesize olefin compounds, which has the advantages of atomic economy, simple steps, high efficiency, green and environmentally friendly synthesis route, and can meet the requirements of industrial application. The synthesis method of the present application is more green, environmentally friendly and widely applicable.

Claims

1. A method for electrochemical synthesis of olefins by green and efficient electrocatalytic hydrogen atom transfer in water, which uses alkyne, water as raw materials, Pd TpBpy-SH as electrocatalyst, and electrical energy as energy source to promote water splitting and produce active hydrogen for transfer to alkyne to synthesize olefins, and the steps are as follows: sequentially adding solvent, electrolyte, alkyne, cathode, anode and reference electrode into an electrolytic cell separated by Nafion 117 anion membrane, stirring at room temperature, and performing reaction under constant voltage, wherein the applied voltage is 1.1-1.4 V, the cathode is carbon paper loaded with Pd TpBpy-SH electrocatalyst, the anode is platinum sheet, and the reference electrode is mercury / mercuric oxide electrode. The carbon paper loaded with Pd TpBpy-SH electrocatalyst is prepared by the following method:

2. The method of claim 1, wherein, (1) dissolving tri-aldehyde-based m-phenol and 5,5'-diamino-2,2'-bipyridine in a mixed solvent of N,N-dimethylacetamide and 1,2-dichlorobenzene, adding acetic acid solution, performing ultrasonic dispersion, freeze-thaw cycle, oven heating reaction, washing, filtering and drying, and grinding to obtain TpBpy COF catalyst; (2) dispersing TpBpy COF catalyst and palladium acetate in dichloromethane, stirring under nitrogen atmosphere, filtering, vacuum drying to obtain Pd-TpBpy COF loaded with metal palladium, and then dissolving the Pd-TpBpy COF loaded with metal palladium, β-mercaptoethylamine in a mixed solvent of anhydrous ethanol and water, stirring, filtering, vacuum drying and grinding to obtain Pd TpBpy-SH catalyst; (3) dispersing Pd TpBpy-SH catalyst, conductive carbon black and polyvinylidene fluoride binder in N-methyl pyrrolidone, mixing uniformly, coating on carbon fiber paper to obtain carbon paper loaded with Pd TpBpy-SH electrocatalyst. In step (1), the molar ratio of tri-aldehyde-based m-phenol to 5,5'-diamino-2,2'-bipyridine is (1-3):(2-5), and the volume ratio of N,N-dimethylacetamide to 1,2-dichlorobenzene is (2-6):

1.

3. The method of claim 2, wherein, In step (1), the mass-volume ratio of tri-aldehyde-based m-phenol to mixed solvent is (18-25):(1-5), unit: mg / mL, the concentration of acetic acid solution is 4-8 M, the volume ratio of acetic acid solution to mixed solvent is (0.1-0.5):(1-5), the heating reaction temperature is 110-140℃, and the reaction time is 3-5 days.

4. The method of claim 2, wherein, In step (2), the mass ratio of TpBpy COF to palladium acetate is (0.8-1):1, the mass-volume ratio of palladium acetate to dichloromethane is (2-3):1, unit: mg / mL, the mass ratio of Pd-TpBpy COF loaded with metal palladium to β-mercaptoethylamine is (40-60):(180-200), and the molar ratio of β-mercaptoethylamine to palladium acetate is (8-12):

1.

5. The method of claim 2, wherein, In step (2), the volume ratio of anhydrous ethanol to water is (2-6):1, and the mass-volume ratio of β-mercaptoethylamine to mixed solvent is (180-200):(8-20), unit: mg / mL.

6. The method of claim 2, wherein, ​ 7. The method of claim 2, wherein, In step (3), the mass ratio of Pd TpBpy-SH electrocatalyst, conductive carbon black, and polyvinylidene fluoride binder is (4-10):(1-3):(1-3), and the mass-volume ratio of Pd TpBpy-SH electrocatalyst to N-methylpyrrolidone is (1-2):(80-100), in units of mg / μL.

8. The method of claim 1, wherein, The electrolyte is potassium hydroxide, and the solvent is a mixture of an organic solvent and water, and the organic solvent is 1,4-dioxane.

9. The method of claim 1, wherein, The volume ratio of dioxane to water is (4-6):(6-4), in units of mL.

10. The method of claim 1, wherein, The solvent, electrolyte, and alkyne are mixed uniformly to form a mixed solution, and the concentration of the electrolyte in the mixed solution is 0.3-0.6 M. The solvent, electrolyte, and alkyne are mixed uniformly to form a mixed solution, and the concentration of the alkyne in the mixed solution is 8-12 mM.

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