A method of electrocatalytic nadh regeneration

Abstract

This invention relates to the field of electrocatalytic hydrogenation, specifically to a method for electrocatalytic NADH regeneration. The method includes the following steps: using copper foam as the anode, platinum wire as the cathode, and KOH solution as the electrolyte, in-situ oxidation is performed using a chronopotential method; the nanowires are then washed with water and ethanol, vacuum dried, and calcined in a tube furnace to obtain CuO nanowires; using the CuO nanowires as the cathode and platinum wire as the anode, the CuO nanowires are in-situ reduced using a chronoamperometry method to obtain Cu nanowires; thioacetamide and acetic acid are added to a copper sulfate solution, stirred to obtain a reaction solution; the Cu nanowires and reaction solution are added to a chemical bath deposition container, heated, washed, and dried to obtain Cu... x S nanowires; electrocatalytic NAD in an inert gas atmosphere + Regeneration of 1,4-NADH; in S4, the electrocatalytic potential is -1.1 to -1.25 V vs. Ag / AgCl. This method enables efficient and selective hydrogenation at the 1,4 position to generate NADH.

Description

Technical Field

[0001] This invention belongs to the field of electrocatalytic hydrogenation, specifically relating to a method for electrocatalytic NADH regeneration. Background Technology

[0002] Artificial photosynthesis is a popular research area for solving environmental and energy problems. Its main process involves converting light energy into chemical energy by simulating natural photosynthesis. Research focuses primarily on three areas: water splitting, carbon dioxide (CO2) fixation, and coenzyme regeneration. Coenzymes are the most widely used key factors in chemical catalysis, involved in over 80% of redox enzyme-catalyzed reactions. They have enormous demand in industrial production and possess significant economic and application value. However, the extremely high cost of coenzyme production and purification greatly limits their widespread application. Reducing the cost of coenzyme production and improving production efficiency has become a key issue in this field. NADH, or reduced nicotinamide adenine dinucleotide, is a cofactor involved in cellular metabolism and energy metabolism. In nature, it is mainly produced in glycolysis during the citric acid cycle and cellular respiration. As an important biological hydrogen carrier and electron donor, it participates in the oxidative phosphate process of the Calvin cycle in the inner mitochondrial membrane, supplying energy to synthesize adenosine triphosphate (ATP). It plays a crucial role in biological enzyme-catalyzed reactions, participating in the vast majority of redox reactions in organisms. NADH and NAD + These are redox pairs that function in cells, undergoing oxidation and reduction reactions and interconverting within the body. Given that most technologies for coenzyme regeneration are complex, costly, energy-intensive, and highly polluting, electrocatalytic coenzyme regeneration is considered a promising green and clean regeneration method.

[0003] In 2022, Academician Li Can and his team from the Zhang Dayu College of Dalian University of Technology and the Dalian Institute of Chemical Physics, Chinese Academy of Sciences, studied the electrocatalytic regeneration of NADH and its reaction mechanism on metal and carbon electrodes. The bioactive 1,4-NADH showed relatively high selectivity on Cu, Fe, and Co electrodes without forming the common NAD2 byproduct.

[0004] In summary, there is an urgent need to provide an efficient electrocatalytic method for selective hydrogenation at the 1,4 positions to generate NADH. Summary of the Invention

[0005] This invention addresses the problem of how to efficiently and selectively hydrogenate NADH at the 1,4 position using an electrocatalytic method.

[0006] To achieve the above objectives, a first aspect of the present invention provides a method for electrocatalytic NADH regeneration, comprising the following steps:

[0007] S1a: Immerse the copper foam in HCl solution, sonicate, rinse with water and acetone, dry, and store in an argon atmosphere for later use.

[0008] S2a: Using S1-treated copper foam as the anode, platinum wire as the cathode, and KOH solution as the electrolyte, in-situ oxidation was carried out using the chronopotential method. After washing with water and ethanol, vacuum drying, and calcination in a tube furnace, CuO nanowires were obtained. Using CuO nanowires as the cathode and platinum wire as the anode, CuO nanowires were reduced in situ using the chronoamperometry method to obtain Cu nanowires.

[0009] S3a: Thioacetamide is added to a copper sulfate solution, followed by a first stirring, then acetic acid is added and stirred again to obtain a reaction solution. Cu nanowires and the reaction solution are then added to a chemical bath deposition container, heated, washed, and dried to obtain Cu. x S nanowires, where x is 1 to 2;

[0010] S4a: Cu x Using S nanowires as the working electrode, Pt sheets as the counter electrode, and an Ag / AgCl electrode as the reference electrode, electrocatalytic NAD was performed under an inert gas atmosphere. + Regenerate 1,4-NADH;

[0011] or,

[0012] S1b: Immerse copper foam in HCl solution, sonicate, rinse with water and acetone, dry and store in an argon atmosphere for later use;

[0013] S2b: Using S1-treated copper foam as the anode, platinum wire as the cathode, and KOH solution as the electrolyte, in-situ oxidation was carried out by chronopotential method. After washing with water and ethanol, vacuum drying, and calcination in a tube furnace, CuO nanowires were obtained.

[0014] S3b: Thioacetamide is added to a copper sulfate solution, followed by a first stirring, then acetic acid is added, followed by a second stirring to obtain a reaction solution. CuO nanowires and the reaction solution are then added to a chemical bath deposition container, heated, washed, and dried to obtain Cu. x S nanowires, where x is 1 to 2;

[0015] S4b: Cu x Using S nanowires as the working electrode, Pt sheets as the counter electrode, and an Ag / AgCl electrode as the reference electrode, electrocatalytic NAD was performed under an inert gas atmosphere. + Regenerate 1,4-NADH;

[0016] In S4a or S4b, the electrocatalytic potential is -1.1 to -1.25 V vs. Ag / AgCl.

[0017] The second aspect of the present invention provides Cu obtained by the above method.x S nanowires.

[0018] The third aspect of the present invention provides the above-described method or the above-described Cu x Application of S nanowires in electrocatalysis.

[0019] The beneficial effects of this invention are: the method provided by this invention can efficiently and selectively generate NADH by hydrogenation at the 1,4 position. Attached Figure Description

[0020] Figure 1 Cu prepared in Example 1 x Scanning electron microscope (SEM) image of S.

[0021] Figure 2 The image shows a scanning electron microscope (SEM) image of the Cu nanowires prepared in Example 1.

[0022] Figure 3 Copper foam, Cu nanowires, and Cu prepared in Example 1 x Comparison of the selectivity of S nanowires for NADH hydrogenation. Detailed Implementation

[0023] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0024] The first aspect of this invention provides a method for electrocatalytic NADH regeneration, comprising the following steps:

[0025] S1a: Immerse the copper foam in HCl solution, sonicate, rinse with water and acetone, dry, and store in an argon atmosphere for later use.

[0026] S2a: Using S1-treated copper foam as the anode, platinum wire as the cathode, and KOH solution as the electrolyte, in-situ oxidation was carried out using the chronopotential method. After washing with water and ethanol, vacuum drying, and calcination in a tube furnace, CuO nanowires were obtained. Using CuO nanowires as the cathode and platinum wire as the anode, CuO nanowires were reduced in situ using the chronoamperometry method to obtain Cu nanowires.

[0027] S3a: Thioacetamide is added to a copper sulfate solution, followed by a first stirring, then acetic acid is added and stirred again to obtain a reaction solution. Cu nanowires and the reaction solution are then added to a chemical bath deposition container, heated, washed, and dried to obtain Cu. x S nanowires, where x is 1 to 2;

[0028] S4a: Cu x Using S nanowires as the working electrode, Pt sheets as the counter electrode, and an Ag / AgCl electrode as the reference electrode, electrocatalytic NAD was performed under an inert gas atmosphere. + Regenerate 1,4-NADH;

[0029] or,

[0030] S1b: Immerse copper foam in HCl solution, sonicate, rinse with water and acetone, dry and store in an argon atmosphere for later use;

[0031] S2b: Using S1-treated copper foam as the anode, platinum wire as the cathode, and KOH solution as the electrolyte, in-situ oxidation was carried out by chronopotential method. After washing with water and ethanol, vacuum drying, and calcination in a tube furnace, CuO nanowires were obtained.

[0032] S3b: Thioacetamide is added to a copper sulfate solution, followed by a first stirring, then acetic acid is added, followed by a second stirring to obtain a reaction solution. CuO nanowires and the reaction solution are then added to a chemical bath deposition container, heated, washed, and dried to obtain Cu. x S nanowires, where x is 1 to 2;

[0033] S4b: Cu x Using S nanowires as the working electrode, Pt sheets as the counter electrode, and an Ag / AgCl electrode as the reference electrode, electrocatalytic NAD was performed under an inert gas atmosphere. + Regenerate 1,4-NADH;

[0034] In S4a or S4b, the electrocatalytic potential is -1.1 to -1.25 V vs. Ag / AgCl.

[0035] In this invention, copper sulfate is introduced as both a copper and sulfur source, and thioacetamide is used as both a sulfur source and a complexing agent. Cu is then directly synthesized in a single step at a relatively low temperature (below 100°C). x S(x=1-2) nanowires: The inventors discovered that thioacetamide contains an amine group that coordinates with Cu, which helps Cu at low temperatures. x The synthesis of S uses thioacetamide (TA) as S. 2- The source of Cu was synthesized at room temperature via a microemulsion template method. x S nanoparticles.

[0036] In this invention, thioacetamide is used as a monomer to combine with metal ions. In the Cu / thioacetamide system, the shear vibration frequency of -NH2 is significantly reduced, while the main CN stretching frequency remains unchanged. If the link between the thioacetamide molecule and the metal surface is through the S atom, the main contribution to the electronic structure will come from the resonance structure (IV). In this case, the order of the CS bond will decrease, so the C-S stretching frequency is expected to decrease. On the other hand, if the bonding is through the N atom, the expected result is the opposite. The introduction of the N atom reduces the energy required for the formation of the Cu-S bond, resulting in higher sulfidation efficiency and stronger Cu-S bond.

[0037] In this invention, the S3 method facilitates the low-temperature synthesis of copper sulfide nanowires.

[0038] In this invention, the successful synthesis of the copper nanowire precursor allows copper sulfide to maintain the morphology of the nanowires during formation. When CuO or Cu(OH)₂ is used as a precursor, sulfidation in this case leads to the formation of CuS nanowires containing Cu... 2+ The proportion of Cu increases, and the use of copper nanowires can make Cu + The proportion is relatively high, while Cu in the current field of hydrogenation reduction... + Relative to Cu 2+ It works even better.

[0039] According to the present invention, in S1a or S1b, the concentration of the HCl solution is 0.1-1M, and the ultrasonication time is 5-10min.

[0040] According to the present invention, in S2a or S2b, the concentration of the KOH solution is 2-5M.

[0041] According to the present invention, in S2a or S2b, the conditions for in-situ oxidation include: the potential range for in-situ oxidation is 0-2V, and the current for in-situ oxidation is 5-20mAcm. -2 The reaction time for in-situ oxidation is 15-25 min.

[0042] According to the present invention, in S2a or S2b, the conditions for vacuum drying include a drying temperature of 60-80°C.

[0043] According to the present invention, in S2a or S2b, the calcination conditions include: calcination in an air atmosphere, a calcination temperature of 160-200°C, and a calcination time of 2-3 hours.

[0044] According to the present invention, in S2a, the conditions for in-situ reduction include: the electrolyte is a PBS solution, the electrolyte pH is 6-8, the electrolyte concentration is 0.05-0.2M, the potential is -1.1 to -1.25V vs. Ag / AgCl, and the energizing time is 10-20min.

[0045] According to the present invention, in S3a or S3b, the molar ratio of copper sulfate to thioacetamide is 1:0.4-0.6, and the molar ratio of copper sulfate to acetic acid is 1:0.2-0.5.

[0046] According to the present invention, in S3a or S3b, the first stirring time is 5-10 min, and the second stirring time is 5-10 min.

[0047] According to the present invention, in S3a or S3b, the heating conditions include: a heating time of 1.5-2.5 hours and a heating temperature of 60-80°C.

[0048] According to the present invention, in S3a or S3b, the conditions for vacuum drying include a drying temperature of 60-70°C.

[0049] According to the present invention, in S34 or S34, the electrocatalytic conditions include: the substrate being reduced nicotinamide adenine dinucleotide disodium salt (NAD). + Reduced nicotinamide adenine dinucleotide disodium salt NAD + The concentration was 0.5-2 mM, the pH for electrocatalysis was 6.8-7.2, and the electrocatalysis time was 60-120 min.

[0050] In this invention, the highest 1,4-NADH regeneration selectivity was measured at pH=7, while at pH=8, due to H... + The low concentration of NADH resulted in slow regeneration and insufficient selectivity. At pH 6, the high hydrogen proton concentration led to faster regeneration, but this high concentration also resulted in disordered hydrogenation, producing large amounts of biologically inactive 1,6-NADH. Subsequent tests at pH 7 with different potentials showed that at -1.3 V vs. Ag / AgCl, the HER process resulted in a large amount of current being used for hydrogen production, leading to lower selectivity and Faraday efficiency. At potentials below -1.1 V vs. Ag / AgCl, the regeneration selectivity and speed were lower than at -1.2 V vs. Ag / AgCl.

[0051] The second aspect of the present invention provides Cu obtained by the above method. x S nanowires.

[0052] The third aspect of the present invention provides the above-described method or the above-described Cu x Application of S nanowires in electrocatalysis.

[0053] Test methods

[0054] Electrochemical tests were conducted using a three-electrode system in an H-type electrolytic cell with a Nafion 117 diaphragm. The counter electrode was a Pt sheet (2cm × 1cm), and the reference electrode was Ag / AgCl (saturated KCl). All potentials were controlled using a CHI 660E electrochemical workstation, and no iR compensation was performed during the tests. The electrocatalytic NADH regeneration experiment was conducted using a potentiostatic electrolysis method.

[0055] The method for measuring the selectivity of electrocatalytic regeneration of 1,4-NADH is the glutamate dehydrogenase method, and the specific operation is as follows:

[0056] The amount of 1,4-NADH was measured by the reaction of 1,4-NADH with α-ketoglutarate and ammonium sulfate in the presence of glutamate dehydrogenase (GDH) to L-glutamate, during which the entire active 1,4-NADH formed during electrolysis was consumed by the enzymatic reaction.

[0057] The GDH solution is prepared as follows: Add 120 mg ammonium sulfate, 20 mg α-ketoglutarate, and 12 μL glutamate dehydrogenase to 10 mL of 0.1 M PBS solution, dissolve, and store in a refrigerator for later use.

[0058] During this reaction, after reacting with the GDH solution (glutamate dehydrogenase + α-ketoglutarate + ammonium sulfate), 1,4-NADH is consumed, and the absorbance at 340 nm in the ultraviolet spectrum decreases. Therefore, based on the change in UV-Vis absorption at 340 nm during electrolysis, the concentration of 1,4-NADH formed before and after the enzymatic reaction can be calculated using the following formula.

[0059] C 1,4-NADH =[A0-(A t -A e )] / ε 1,4-NADH

[0060] In the formula, A0 is the initial absorbance before the enzyme-catalyzed reaction, and A t The final absorbance A after the enzyme-catalyzed reaction e ε represents the absorbance of the enzyme solution system. 1,4-NADH The absorbance coefficient was obtained from the 1,4-NADH UV standard curve.

[0061] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Obviously, the embodiments described herein are only some embodiments of the present invention and are not intended to limit the present invention. Based on the embodiments of the present invention, all other embodiments implemented by those skilled in the art without making creative improvements are within the protection scope of the present invention.

[0062] Example 1:

[0063] S1a: Cut the copper foam (CF) into 1x2cm pieces, immerse them in 1M HCl solution, and ultrasonically clean them for 10 minutes to remove the oxide layer on the surface. Then remove the copper foam, rinse it with water and acetone, blow it dry, and store it under an argon atmosphere for later use.

[0064] S2a: First, the CuO nanowire precursor was prepared using the following method: 3.0 M KOH was dissolved in deionized water as the electrolyte. Pretreated CF was used as the anode, and a platinum wire electrode as the cathode. The mixture was placed in a two-electrode electrolytic cell, and in-situ oxidation was performed using a chronopotential method. The potential range was 0.00-2.00 V, and the current density was 10 mA / cm². -2 The reaction time was 20 min. After the reaction, blue Cu(OH)₂ nanowires formed on the surface of CF. After continuous rinsing with water and ethanol, it was placed in a vacuum drying oven at 65°C overnight. Subsequently, the dried Cu(OH)₂ nanowires were placed in a tube furnace and calcined at 180°C in air atmosphere for 2 h. After cooling, black CuO nanowires were obtained. The CuO nanowires were reduced in situ using a chronoamperometry method. The cathode was CuO nanowires, the anode was platinum wire, the electrolyte was 0.1M PBS solution with pH=7, and the potential was -1.1V vs. Ag / AgCl. After 15 min of energization, the electrode was observed to slowly turn red, yielding Cu nanowires (Cu NWs / CF).

[0065] S3a: First, dissolve 0.1M copper sulfate pentahydrate in 50mL distilled water using a magnetic stirrer for 10min. Add 50mmol of thioacetamide and stir until homogeneous. Finally, add 35mmol of acetic acid and stir for 30min. Transfer the final reaction solution to a chemical bath deposition (CBD) vessel, place the prepared Cu nanowires vertically in the vessel, heat at 65℃ for 2h, allow the vessel to cool naturally, then wash the electrodes sequentially with ethanol and distilled water, and finally dry in a vacuum drying oven at 65℃ for 24h.

[0066] S4a: NADH directional regeneration is carried out in a three-electrode system, where Cu x The S NWs / CF electrode was used as the working electrode, the Pt sheet as the counter electrode, and the Ag / AgCl electrode as the reference electrode. The electrolytic potential was -1.2V vs. Ag / AgCl. The electrolyte solution was 0.1M phosphate-buffered saline (PBS) pH=7. A sealed H-type electrolytic cell was used, and the reaction temperature was room temperature (25℃). The entire electrolysis process was protected under an Ar atmosphere. The substrate was 1mM reduced nicotinamide adenine dinucleotide disodium salt (NAD). + ).

[0067] Example 2

[0068] Electrocatalysis of NAD according to the method of Example 1+ The difference is that the electrocatalytic potential in S4a is -1.1V vs. Ag / AgCl.

[0069] Example 3

[0070] Electrocatalysis of NAD according to the method of Example 1 + The difference is that the electrocatalytic potential in S4a is -1.25V vs. Ag / AgCl.

[0071] Example 4

[0072] Electrocatalysis of NAD according to the method of Example 1 + The difference is that the electrocatalytic pH in S4a is 6.8.

[0073] Example 5

[0074] Electrocatalysis of NAD according to the method of Example 1 + The difference is that the electrocatalytic pH in S4a is 7.2.

[0075] Example 6

[0076] S1b: Cut copper foam (CF) into 1x2 cm pieces, immerse them in 1M HCl solution, and ultrasonically clean them for 10 minutes to remove the oxide layer on the surface. Then remove the copper foam, rinse it with water and acetone, blow it dry, and store it under an argon atmosphere for later use.

[0077] S2b: First, the CuO nanowire precursor was prepared using the following method: 3.0 M KOH was dissolved in deionized water as the electrolyte. Pretreated CF was used as the anode, and a platinum wire electrode as the cathode. The mixture was placed in a two-electrode electrolytic cell, and in-situ oxidation was performed using a chronopotential method. The potential range was 0.00-2.00 V, and the current density was 10 mA / cm². -2 The reaction time was 20 min. After the reaction, blue Cu(OH)₂ nanowires formed on the CF surface. After continuous rinsing with water and ethanol, the nanowires were placed in a vacuum drying oven at 70°C overnight. Subsequently, the dried Cu(OH)₂ nanowires were placed in a tube furnace and calcined at 180°C in air atmosphere for 2 h. After cooling, black CuO nanowires were obtained.

[0078] S3b: First, dissolve 0.1M copper sulfate pentahydrate in 50mL distilled water using a magnetic stirrer for 10min. Add 50mmol of thioacetamide and stir until homogeneous. Finally, add 35mmol of acetic acid and stir for 30min. Transfer the final reaction solution to a chemical bath deposition (CBD) vessel. Place the prepared Cu nanowires vertically in the vessel and heat at 65℃ for 2h. Allow the vessel to cool naturally, then wash the electrodes sequentially with ethanol and distilled water. Finally, dry in a vacuum drying oven at 65℃ for 24h.

[0079] S4b: NADH directional regeneration is carried out in a three-electrode system, where Cu x The S NWs / CF electrode was used as the working electrode, the Pt sheet as the counter electrode, and the Ag / AgCl electrode as the reference electrode. The electrolytic potential was -1.2V vs. Ag / AgCl. The electrolyte solution was 0.1M phosphate-buffered saline (PBS) pH=7. A sealed H-type electrolytic cell was used, and the reaction temperature was room temperature (25℃). The entire electrolysis process was protected under an Ar atmosphere. The substrate was 1mM reduced nicotinamide adenine dinucleotide disodium salt (NAD). + ).

[0080] Example 7

[0081] Electrocatalysis of NAD according to the method of Example 6 + The difference is that the electrocatalytic potential in S4b is -1.1V vs. Ag / AgCl.

[0082] Example 8

[0083] Electrocatalysis of NAD according to the method of Example 6 + The difference is that the electrocatalytic potential in S4b is -1.25V vs. Ag / AgCl.

[0084] Example 9

[0085] Electrocatalysis of NAD according to the method of Example 6 + The difference is that the electrocatalytic pH in S4b is 6.8.

[0086] Example 10

[0087] Electrocatalysis of NAD according to the method of Example 6 + The difference is that the electrocatalytic pH in S4b is 7.2.

[0088] Comparative Example 1

[0089] Electrocatalysis of NAD according to the method of Example 1 + The difference is that Cu x S is copper sulfide produced by high-temperature heat treatment of copper foam (CF) with sulfur powder in a tube furnace.

[0090] Comparative Example 2

[0091] Electrocatalysis of NAD according to the method of Example 1 + The difference is that the electrocatalytic potential in S4a is -1.0V vs. Ag / AgCl.

[0092] Comparative Example 3

[0093] Electrocatalysis of NAD according to the method of Example 1+ The difference is that the electrocatalytic potential in S4a is -1.4V vs. Ag / AgCl.

[0094] Comparative Example 4

[0095] Electrocatalysis of NAD according to the method of Example 1 + The difference is that the electrocatalytic pH in S4a is 6.5.

[0096] Comparative Example 5

[0097] Electrocatalysis of NAD according to the method of Example 1 + The difference is that the electrocatalytic pH in S4a is 7.5.

[0098] Comparative Example 6

[0099] Electrocatalysis of NAD according to the method of Example 6 + The difference is that the electrocatalytic potential in S4b is -1.0V vs. Ag / AgCl.

[0100] Comparative Example 7

[0101] Electrocatalysis of NAD according to the method of Example 6 + The difference is that the electrocatalytic potential in S4b is -1.3V vs. Ag / AgCl.

[0102] Comparative Example 8

[0103] Electrocatalysis of NAD according to the method of Example 6 + The difference is that the electrocatalytic pH in S4b is 6.5.

[0104] Comparative Example 9

[0105] Electrocatalysis of NAD according to the method of Example 6 + The difference is that the electrocatalytic pH in S4b is 7.5.

[0106] The selectivity of electrocatalytic hydrogenation of 1,4-NADH in Examples 1-10 and Comparative Examples 1-9 is shown in Table 1.

[0107] Table 1

[0108]

[0109]

[0110] As can be seen from the examples and comparative examples, the preparation method of the present invention can electrocatalyze the production of NAD+ with high selectivity. + 1,4-NADH was prepared as a substrate.

[0111] The electrocatalytic potentials of Comparative Examples 3 and 7 were -1.4 V vs. Ag / AgCl. The poor selectivity was due to the excessively high potential causing H+ to be released. ad When the energy is too high, the hydrogenation sites become disordered.

[0112] The method provided in this application enables the in-situ growth of copper sulfide nanowires (CuO nanowires) using Cu nanowires or CuO nanowires as precursors. x The S NWs / CF catalyst exhibits a hydrogenation selectivity of up to 90.3% at the 1,4 positions.

[0113] Figure 1 Cu prepared in Example 1 x The scanning electron microscope (SEM) image of S NWs / CF shows that Cu x The SNWs / CF exhibits a nanowire morphology, with an overall morphology identical to that of the Cu NWs / CF precursor. The nanowires are approximately 100-800 nm in length and 15-40 nm in diameter, with some nanospheres present on the nanowires, confirming the correct synthesis of the copper sulfide nanowire morphology.

[0114] Figure 2 The image shows a scanning electron microscope (SEM) image of the Cu nanowires prepared in Example 1. It can be seen that the Cu nanowires are uniformly grown on the CF framework. The length of the nanowires is about 100-800 nm and the diameter is 15-40 nm, confirming that the precursor morphology was synthesized correctly.

[0115] Figure 3 Copper foam, Cu nanowires, and Cu prepared in Example 1 x The comparison diagram of the NADH hydrogenation selectivity of Cu nanowires shows that the regeneration selectivity of 1,4-NADH by the Cu NWs / CF catalyst is higher than that of unmodified copper foam, indicating that this morphology has certain advantages for selective hydrogenation. Meanwhile, the sulfided Cu... x The hydrogenation selectivity of the S NWs / CF electrode was significantly improved, indicating that the introduction of sulfur doping has a significant promoting effect on improving hydrogenation at the 1,4 positions.

[0116] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for electrocatalytic NADH regeneration, characterized in that, Includes the following steps: S1a: Immerse the copper foam in HCl solution, sonicate, rinse with water and acetone, dry, and store in an argon atmosphere for later use. S2a: Using S1-treated copper foam as the anode, platinum wire as the cathode, and KOH solution as the electrolyte, in-situ oxidation was carried out using the chronopotential method. After washing with water and ethanol, vacuum drying, and calcination in a tube furnace, CuO nanowires were obtained. Using CuO nanowires as the cathode and platinum wire as the anode, CuO nanowires were reduced in-situ using the chronoamperometry method to obtain Cu nanowires. S3a: Thioacetamide is added to a copper sulfate solution, followed by a first stirring, then acetic acid is added and stirred again to obtain a reaction solution. Cu nanowires and the reaction solution are then added to a chemical bath deposition container, heated, washed, and dried to obtain Cu. x S nanowires, where x is 1~2; S4a: Cu x S nanowires were used as the working electrode, Pt sheets as the counter electrode, and Ag / AgCl electrodes as the reference electrode. Electrocatalytic NAD was performed under an inert gas atmosphere. + Regenerate 1,4-NADH; or, S1b: Immerse copper foam in HCl solution, sonicate, rinse with water and acetone, dry and store in an argon atmosphere for later use; S2b: Using S1-treated copper foam as the anode, platinum wire as the cathode, and KOH solution as the electrolyte, in-situ oxidation was carried out by chronopotential method. After washing with water and ethanol, vacuum drying, and calcination in a tube furnace, CuO nanowires were obtained. S3b: Thioacetamide is added to a copper sulfate solution, followed by a first stirring, then acetic acid is added, followed by a second stirring to obtain a reaction solution. CuO nanowires and the reaction solution are then added to a chemical bath deposition container, heated, washed, and dried to obtain Cu. x S nanowires, where x is 1~2; S4b: Cu x S nanowires were used as the working electrode, Pt sheets as the counter electrode, and Ag / AgCl electrodes as the reference electrode. Electrocatalytic NAD was performed under an inert gas atmosphere. + Regenerate 1,4-NADH; In S4a or S4b, the electrocatalytic potential is -1.1 to -1.25 V vs. Ag / AgCl; In S4a or S4b, the electrocatalytic conditions include: the substrate being reduced nicotinamide adenine dinucleotide disodium salt (NAD). + Reduced nicotinamide adenine dinucleotide disodium salt NAD + The concentration was 0.5-2 mM, the pH for electrocatalysis was 6.8-7.2, and the electrocatalysis time was 60-120 min.

2. The method according to claim 1, characterized in that, In S1a or S1b, the concentration of the HCl solution is 0.1-1M, and the ultrasonication time is 5-10 minutes.

3. The method according to claim 1, characterized in that, In S2a or S2b, the concentration of the KOH solution is 2-5M.

4. The method according to claim 1, characterized in that, In S2a or S2b, the conditions for in-situ oxidation include: an in-situ oxidation potential range of 0-2 V and an in-situ oxidation current of 5-20 mA cm⁻¹. -2 The reaction time for in-situ oxidation is 15-25 min.

5. The method according to claim 1, characterized in that, In S2a or S2b, the vacuum drying conditions include: a drying temperature of 60-80℃; In S2a or S2b, the calcination conditions include: calcination in an air atmosphere, a calcination temperature of 160-200℃, and a calcination time of 2-3 hours; In S2a, the conditions for in-situ reduction include: the electrolyte is PBS solution, the electrolyte pH is 6-8, the electrolyte concentration is 0.05-0.2M, the potential is -1.1~-1.3 V vs. Ag / AgCl, and the energizing time is 10-20 min.

6. The method according to claim 1, characterized in that, In S3a or S3b, the molar ratio of copper sulfate to thioacetamide is 1:0.4-0.6, and the molar ratio of copper sulfate to acetic acid is 1:0.2-0.

5.

7. The method according to claim 1, characterized in that, In S3a or S3b, the first stirring time is 5-10 min, and the second stirring time is 5-10 min; In S3a or S3b, the heating conditions include: a heating time of 1.5-2.5 hours and a heating temperature of 60-80°C; in S3a or S3b, the vacuum drying conditions include: a drying temperature of 60-70°C.

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