In-situ high-resolution nuclear magnetic resonance measurement device and method for carbon dioxide electro-reduction reaction

Abstract

The application discloses a kind of high-resolution nuclear magnetic resonance in-situ measuring device and method for carbon dioxide electro-reduction reaction, the device includes in-situ nuclear magnetic resonance tube, fixed tube, insulation tube, ventilation pipe, counter electrode, reference electrode, working electrode and cap, working electrode is coated with catalyst for carbon dioxide electro-reduction reaction, in-situ nuclear magnetic resonance tube includes first tube part and second tube part of different diameters, working electrode and ventilation pipe are fixedly connected with fixed tube and extend into first tube part, only working electrode is located in sample detection area, the bottom of insulation tube is covered with ion exchange membrane, ion exchange solution is placed in insulation tube, counter electrode is fixedly installed in insulation tube, reaction liquid is placed in in-situ nuclear magnetic resonance tube, while continuously in ventilation pipe carbon dioxide is introduced to carry out electro-reduction, using resistance inhomogeneous field detection technology realizes in-situ high-resolution spectrum acquisition, and the qualitative and quantitative information of electro-reduction carbon dioxide reaction liquid phase product is acquired in real time.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of in-situ electrochemistry-nuclear magnetic resonance and carbon dioxide reduction, and particularly to a high-resolution nuclear magnetic resonance in-situ measurement device and method for carbon dioxide electro-reduction reaction. BACKGROUND

[0002] Carbon dioxide electro-reduction research focuses on converting carbon dioxide into valuable fuels and chemicals using electrical energy, and in particular, directly reducing carbon dioxide into some liquid products such as formic acid, methanol, ethanol, etc. with high added value has good prospects. Nuclear magnetic resonance technology is currently an effective measurement means for directly quantifying liquid-phase products of electro-reduction of carbon dioxide, but most reports collect solutions after the reaction is completed for nuclear magnetic measurement, which cannot realize monitoring of the in-situ reaction process. Currently, only Michael Schatz et al. have proposed an electrolytic cell design for carbon dioxide electro-reduction combined with nuclear magnetic resonance spectroscopy technology, but the electrolytic cell cannot realize real-time in-situ nuclear magnetic resonance measurement of carbon dioxide gas, and can only use electrolyte with pre-dissolved carbon dioxide for electrolysis, which cannot accurately reflect the in-situ electro-reduction reaction process of carbon dioxide. In addition, the design directly uses a three-electrode system in a single electrolysis chamber for research, and the oxidation reaction of the electrode will directly interfere with the determination of the reduction products of the working electrode.

[0003] In-situ electrochemistry-nuclear magnetic resonance can realize non-invasive real-time detection of electrochemical reaction processes, and can be used to monitor real-time changes of reactants, intermediate products, and final liquid products of carbon dioxide reduction reactions, which is beneficial to revealing the reaction mechanism of carbon dioxide reduction. However, for reactions that require continuous introduction of gas into the electrolyte, the spectrum data collected by the conventional nuclear magnetic detection method will cause magnetic field inhomogeneity in the liquid-phase nuclear magnetic resonance detection region under the gas introduction state, and thus the resolution and sensitivity of the NMR spectrum will be low, which cannot be used for reaction process analysis and product quantification. The Spatially-Selective sequence uses a Gaussian pulse and a Z-direction gradient field to cooperate to selectively excite the sample in space, thereby reducing the influence of magnetic field inhomogeneity on the signal when the entire monitoring region is excited, so as to achieve the purpose of resisting the influence of magnetic field inhomogeneity. Currently, this sequence has not been involved in real-time detection of electrochemical reactions in liquid-phase nuclear magnetic resonance with gas medium. SUMMARY

[0004] The present application aims to overcome the deficiencies in the prior art and provide a high-resolution nuclear magnetic resonance in-situ measurement device and method for carbon dioxide electro-reduction reaction.

[0005] In order to achieve the above purpose, the technical scheme of the present application is as follows:

[0006] The utility model provides a kind of high-resolution nuclear magnetic resonance in-situ measuring device for carbon dioxide electro-reduction reaction, including in-situ nuclear magnetic resonance tube, fixed pipe, insulation pipe, ventilation pipe, three electrodes and cap, the three electrodes include counter electrode, reference electrode and working electrode, the working electrode is coated with catalyst for carbon dioxide electro-reduction reaction, the in-situ nuclear magnetic resonance tube includes first pipe part and second pipe part of different diameters, the first pipe part is arranged below the second pipe part and is equipped with the sample detection area of nuclear magnetic resonance spectrometer, the working electrode and the ventilation pipe are fixedly connected with the fixed pipe and extend to the first pipe part, only the working electrode in the three electrodes is partially located in the sample detection area, the counter electrode is fixedly installed in the insulation pipe, the bottom of the insulation pipe is covered and fixed with ion exchange membrane, the reference electrode and the insulation pipe are installed in the second pipe part and are spaced apart from the fixed pipe, the ventilation pipe is arranged in the inside of the fixed pipe, for carbon dioxide gas, the cap is covered on the top of the second pipe part, ion exchange solution for carbon dioxide electro-reduction reaction is placed in the insulation pipe, and its liquid level covers at least the counter electrode, reaction liquid for carbon dioxide electro-reduction reaction is placed in the in-situ nuclear magnetic resonance tube, and its liquid level covers at least the reference electrode and the ion exchange membrane.

[0007] As preferred, the working electrode, counter electrode and reference electrode are connected with first lead wire, second lead wire and third lead wire respectively, the first lead wire, second lead wire and third lead wire pass through the holes on the cap and are connected with electrochemical workstation respectively.

[0008] As preferred, the first lead wire and the ventilation pipe pass through the inside of the fixed pipe in parallel and are fixedly connected at the bottom of the fixed pipe respectively.

[0009] As preferred, the material of the working electrode includes carbon fiber, the material of the reference electrode includes silver wire, and the material of the counter electrode includes platinum wire.

[0010] As preferred, it further includes carbon dioxide gas cylinder and gas flow control meter, the ventilation pipe is connected with the gas flow control meter and carbon dioxide gas cylinder, and the flow of carbon dioxide in the ventilation pipe is adjusted by the gas flow control meter.

[0011] As preferred, the in-situ nuclear magnetic resonance tube is spliced by the first pipe part and the second pipe part, the diameter of the first pipe part is 5mm, and the diameter of the second pipe part is 10mm.

[0012] As preferred, the ventilation pipe includes PTFE pipe, and the diameter is 0.3-1mm, the fixed pipe and insulation pipe include glass pipe, and the outer diameter is 3-4mm and the inner diameter is 2-3.5mm.

[0013] A high-resolution nuclear magnetic resonance in-situ measurement method for carbon dioxide electro-reduction reaction, using the high-resolution nuclear magnetic resonance in-situ measurement device for carbon dioxide electro-reduction reaction, the method comprising the following steps:

[0014] 1) injecting a reaction solution for carbon dioxide electro-reduction reaction into an in-situ nuclear magnetic resonance tube, assembling a three-electrode and a gas tube, and inserting the three-electrode and the gas tube into the in-situ nuclear magnetic resonance tube after testing a passage, covering a cap on the in-situ nuclear magnetic resonance tube, the three-electrode being externally connected to an electrochemical workstation through a cable, turning on the electrochemical workstation, selecting electrochemical measurement software and related parameters, and transporting carbon dioxide into the in-situ nuclear magnetic resonance tube through the gas tube;

[0015] 2) adjusting a gas flow rate and setting sequence parameters for resisting inhomogeneous fields, starting the electrochemical workstation, performing electro-catalytic reduction reaction on carbon dioxide, and collecting high-resolution nuclear magnetic resonance spectrum signals on a liquid-phase nuclear magnetic resonance spectrometer.

[0016] Preferably, the step 1 of assembling the three-electrode and the gas tube specifically comprises:

[0017] coating a catalyst for carbon dioxide reduction reaction on a working electrode and drying, connecting the working electrode coated with the catalyst to a first wire, and passing the working electrode coated with the catalyst through an inside of a fixed tube in parallel with the gas tube, and fixing the working electrode coated with the catalyst at a lower end of the fixed tube;

[0018] wrapping an ion exchange membrane on a lower end of an isolation tube, injecting an ion exchange solution for carbon dioxide electro-reduction reaction into the isolation tube, inserting a counter electrode into the ion exchange solution in the isolation tube, fixing the counter electrode at an upper end of the isolation tube and connecting the counter electrode to a second wire;

[0019] connecting a reference electrode to a third wire.

[0020] Preferably, the sequence for resisting inhomogeneous fields comprises a Spatially-Selective pulse sequence, and parameters of the Spatially-Selective pulse sequence include an experimental temperature, a scanning number, a sampling time, a spectrum width, and a selection pulse width.

[0021] Compared with the prior art, the present application has the following beneficial effects:

[0022] (1) In the three-electrode system of the present application, the counter electrode is placed in the isolation tube wrapped with the ion exchange membrane at the bottom, and the saturated KCl solution is injected into the isolation tube to support the ion exchange conduction, so that the electrolyte environment of the counter electrode is physically separated from the electrolyte environment of the working electrode, to prevent the carbon dioxide reduction products generated at the working electrode from being oxidized and consumed at the counter electrode, and to interfere with the detection.

[0023] (2) The application adopts Spatially-Selective spatial selection sequence to collect nuclear magnetic spectrum, reduces the influence of magnetic field unevenness on signal when exciting the whole detection area, and achieves the effect of resisting the uneven influence of air medium in liquid on the magnetic field caused by the input of carbon dioxide gas.

[0024] (3) The three electrodes of the application can be replaced according to different needs of electrochemical reactions, have reference significance for monitoring various electrochemical reactions under the condition of continuous input of gas by using nuclear magnetic resonance technology, and are suitable for various electrocatalytic reactions of carbon dioxide reduction; the reactants, intermediate products and generated liquid products can be detected in real time and quantitatively by nuclear magnetic resonance, the carbon dioxide reduction reaction process is monitored, and the reaction mechanism is revealed. BRIEF DESCRIPTION OF DRAWINGS

[0025] The accompanying drawings are included to provide a further understanding of embodiments and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments and serve the purpose of explaining principles of the application. Other embodiments and many of the intended advantages of the embodiments will be readily appreciated as the same becomes better understood by reference to the following detailed description.

[0026] Figure 1 A schematic diagram of a high-resolution nuclear magnetic resonance in-situ measurement device for carbon dioxide electro-reduction reaction of an embodiment of the present application;

[0027] Figure 2 A high-resolution nuclear magnetic resonance in-situ method for carbon dioxide electro-reduction reaction of an embodiment of the present application uses a conventional water compression sequence method to collect and measure one-dimensional 1 H NMR spectrum in the process of copper-catalyzed carbon dioxide electro-reduction under the condition of aeration before the start of electro-reduction;

[0028] Figure 3 A high-resolution nuclear magnetic resonance in-situ method for carbon dioxide electro-reduction reaction of an embodiment of the present application uses a conventional water compression sequence method and a spatial selection sequence method to collect and measure one-dimensional 1 H NMR spectrum in the process of copper-catalyzed carbon dioxide electro-reduction under the condition of aeration after the start of electro-reduction of 3H;

[0029] Figure 4 A high-resolution nuclear magnetic resonance in-situ method for carbon dioxide electro-reduction reaction of an embodiment of the present application uses a conventional water compression sequence method and a spatial selection sequence method to collect and measure one-dimensional 1 H NMR spectrum in the process of copper-catalyzed carbon dioxide electro-reduction under the condition of aeration after the start of electro-reduction of 3H;

[0030] Reference signs: 1, in-situ nuclear magnetic resonance tube; 11, first tube part; 12, second tube part; 2, fixed tube; 3, insulation tube; 4, vent tube; 51, counter electrode; 52, reference electrode; 53, working electrode; 6, cap; 71, first wire; 72, second wire; 73, third wire; 8, ion exchange membrane; 9, detection area. DETAILED DESCRIPTION

[0031] The application will be further described below in detail with reference to the accompanying drawings and examples. It can be understood that the specific examples described herein are only used to explain the related application, and not to limit the application. In addition, it should be noted that only the parts related to the application are shown in the drawings for ease of description.

[0032] It should be noted that the examples in the present application and the features in the examples can be combined with each other without conflict. The present application will be described in detail below with reference to the accompanying drawings and examples.

[0033] In the embodiment of the present application, a high-resolution in-situ nuclear magnetic resonance measurement device for carbon dioxide electro-reduction reaction is provided, which comprises an in-situ nuclear magnetic resonance tube 1, a fixed tube 2, an insulation tube 3, a vent tube 4, three electrodes and a cap 6, the three electrodes comprising a counter electrode 51, a reference electrode 52 and a working electrode 53, specifically, the material of the working electrode 53 comprises carbon fiber, the material of the reference electrode 52 comprises silver wire with a diameter of 0.5 mm, and the material of the counter electrode 51 comprises platinum wire with a diameter of 0.5 mm, the three electrodes can be replaced according to the needs of different electrochemical reactions, the working electrode 53, the counter electrode 51 and the reference electrode 52 are connected with a first wire 71, a second wire 72 and a third wire 73 respectively, a double-conductive copper foil tape can be used to connect the electrodes and the wires, and a PTFE heat shrink sleeve is wrapped around the connection, the first wire 71, the second wire 72 and the third wire 73 pass through the corresponding holes in the cap 6 and are connected with an electrochemical workstation, the cap 6 has a pre-formed circular hole, and the electrochemical workstation is connected externally by a cable. The working electrode 53 is coated with a catalyst for carbon dioxide electro-reduction reaction, which can be coated by physical or chemical methods, and the catalyst can be a conductive material such as nano-copper particles.

[0034] Specifically, the in-situ NMR tube 1 includes a first tube part 11 and a second tube part 12 with different diameters, and is spliced by the two, the diameter of the first tube part 11 is 5mm, and the diameter of the second tube part 12 is 10mm. In one embodiment, the in-situ NMR tube 1 can be spliced by NMR sample tubes with diameters of 10mm and 5mm, the upper end is an NMR sample tube with a diameter of 10mm, and the lower end is an NMR sample tube with a diameter of 5mm. The first tube part 11 is arranged below and communicated with the second tube part 12, and a sample detection area 9 of the NMR spectrometer is arranged on the first tube part 11, a magnetic field is applied to the sample detection area 9 when the NMR spectrometer works, and high-resolution NMR spectrum signals can be collected at the same time. The working electrode 53 and the gas tube 4 are fixedly connected with the fixed tube 2 and extend into the first tube part 11, and only the working electrode 53 of the three electrodes is located in the sample detection area 9. The counter electrode 51 is fixedly installed in the isolation tube 3, the bottom of the isolation tube 3 is covered and fixed with the ion exchange membrane 8, and the ion exchange membrane 8 is fixed on the isolation tube 3 through the PTFE heat shrink sleeve. The ion exchange solution for carbon dioxide electro-reduction reaction is placed in the isolation tube 3, and the liquid surface thereof covers at least the counter electrode 51. Specifically, the ion exchange solution for carbon dioxide electro-reduction reaction can be saturated KCl solution, the isolation tube 3 includes a glass tube, and the ion exchange membrane 8 is fixed between the isolation tube 3 through the PTFE heat shrink sleeve. The counter electrode 51 is placed in the glass tube at the bottom covered by the ion exchange membrane 8, saturated KCl solution is injected into the glass tube to support conductive ion exchange, so that the ion exchange solution environment of the counter electrode 51 and the reaction liquid environment of the working electrode 53 are physically separated, so as to prevent the carbon dioxide reduction products generated at the working electrode 53 from being oxidized and consumed at the counter electrode 51, and interference with detection.

[0035] Further, the reference electrode 52 and the isolation tube 3 are installed in the second tube part 12 and are spaced apart from the fixed tube 2, and in the preferred embodiment, the fixed tube 2 is also a glass tube, the outer diameter of the fixed tube 2 and the isolation tube is 3mm, and the inner diameter is 2mm, the first lead wire 71 and the vent tube 4 pass through the inside of the fixed tube 2 in parallel. The vent tube 4 is used to pass in carbon dioxide gas, specifically, the vent tube 4 includes a PTFE tube with a diameter of 1mm, the vent tube 4 is connected with a gas flow control meter and a carbon dioxide gas cylinder, and the flow of carbon dioxide in the vent tube 4 is adjusted through the gas flow control meter. The first lead wire 71 and the working electrode 53 are connected at the bottom of the fixed tube 2, the working electrode 53 and the vent tube 4 are fixed at the bottom of the fixed tube 2 by epoxy resin and extend downward, the cap 6 is capped on the top of the second tube part 12, the reaction solution for the carbon dioxide electro-reduction reaction is placed in the in-situ NMR tube 1, and the liquid surface thereof covers at least the reference electrode 52 and the ion exchange membrane 8. The working electrode 53 and the counter electrode 51 are connected to form a loop to pass through the current to cause the carbon dioxide electro-reduction reaction in the in-situ NMR tube 1. The device can obtain the continuous nuclear magnetic resonance spectrum of the carbon dioxide reduction reaction product, the intermediate state product and the final liquid product under the condition of passing in carbon dioxide gas, and can be real-time qualitative and quantitative to truly reveal the carbon dioxide electro-reduction reaction mechanism.

[0036] The embodiment of the present application also proposes a high-resolution nuclear magnetic resonance in-situ measurement method for carbon dioxide electro-reduction reaction, which uses the above-mentioned high-resolution nuclear magnetic resonance in-situ measurement device for carbon dioxide electro-reduction reaction, and the method comprises the following steps:

[0037] (1) 1mL of the reaction solution for carbon dioxide electro-reduction reaction is injected into the in-situ NMR tube 1, specifically, the reaction solution for carbon dioxide electro-reduction reaction is saturated treated by passing in carbon dioxide gas after being treated according to the preset formula, and 1mL of the pre-saturated treated reaction solution is taken.

[0038] (2) Assemble the three electrodes and the gas tube 4, and insert them into the in-situ NMR tube 1 after testing the passage. First, verify the conductivity of the entire three-electrode system and the assembled system using a conventional multimeter, and then insert them into the in-situ NMR tube 1 after ensuring that all three electrodes are conducting. Specifically, coat the catalyst for the carbon dioxide reduction reaction on the working electrode 53 and dry it, connect the working electrode 53 coated with the catalyst to the first wire 71, and pass it through the inside of the fixed tube 2 in parallel with the gas tube 4, and fix it at the lower end of the fixed tube 2. Wrap and fix the ion exchange membrane 8 at the lower end of the isolation tube 3, inject the ion exchange solution for the carbon dioxide reduction reaction into the isolation tube 3, insert the counter electrode 51 into the ion exchange solution in the isolation tube 3, fix the counter electrode 51 at the upper end of the isolation tube 3 and connect it to the second wire 72, and connect the reference electrode 52 to the third wire 73. Cover the cap 6 on the in-situ NMR tube 1, and connect the three electrodes to the electrochemical workstation through the cable, turn on the electrochemical workstation, select the electrochemical measurement software and related parameters, and deliver carbon dioxide through the gas tube 4 into the in-situ NMR tube 1.

[0039] (3) Adjust and set the carbon dioxide gas flow rate, connect the electrochemical workstation for cyclic voltammetry test after stabilization to determine the carbon dioxide reduction potential. First, temporarily stop inputting carbon dioxide gas, insert the device into the liquid NMR spectrometer, and perform conventional tuning, shimming, and field locking operations without carbon dioxide gas. Input carbon dioxide gas and set the same gas flow rate as in the above step. At this time, the magnetic field is not uniform due to the presence of the gas medium, and even if sufficient shimming is performed, the influence of the non-uniformity of the magnetic field cannot be eliminated, and the resolution of the NMR spectrum collected at this time is greatly affected. Adjust the gas flow rate to maintain the input of carbon dioxide gas, set the sequence parameters to resist the non-uniform field, start the electrochemical workstation, perform electrocatalytic reduction of carbon dioxide, and collect high-resolution NMR spectrum signals on the liquid NMR spectrometer to achieve full-process monitoring and data collection of liquid products during the carbon dioxide reduction reaction.

[0040] In specific embodiments, the sequence to resist the non-uniform field includes a Spatially-Selective pulse sequence, and the corresponding parameters include the experimental temperature, the number of scans, the sampling time, the spectral width, and the selection pulse width. Using the Spatially-Selective sequence for NMR spectrum collection can reduce the influence of the non-uniformity of the magnetic field on the signal when exciting the entire sample detection area 9, achieving the effect of resisting the non-uniform influence of the magnetic field caused by the presence of air medium in the liquid due to the input of carbon dioxide gas.

[0041] This method is applicable to various electrocatalytic reactions of carbon dioxide reduction. Reactants, intermediate products, and generated liquid products can all be detected in real time and quantitatively using NMR, which can monitor the carbon dioxide reduction process and reveal its reaction mechanism.

[0042] The following describes, in conjunction with an embodiment, a high-resolution nuclear magnetic resonance measurement of the substance suitable for the electroreduction reaction of carbon dioxide.

[0043] This embodiment uses copper-catalyzed carbon dioxide electroreduction as an example. The electrolyte is 1M potassium bicarbonate, and the solvent is deuterium water containing 0.03% sodium 3-trimethylsilyl-1-propanesulfonate (as a standard). Data were collected before and after the electroreduction reaction under continuous carbon dioxide gas purging. The working electrode 53 is made of carbon fiber coated with nano-copper powder. Specifically, 1 mL of electrolyte pre-saturated with carbon dioxide for 30 min is injected into the in-situ NMR tube 1, which is formed by splicing the first and second tube sections. The entire three-electrode system and the venting tube 4 are inserted into the in-situ NMR tube 1, and the cap 6 is placed on top. The three electrodes are connected to a CHI660E electrochemical workstation via cables, and the venting tube 4 is connected to a carbon dioxide storage cylinder via a gas flow controller. After the electrodes and venting tube 4 are connected, the electrochemical workstation switch and CHI660E software are turned on. The constant potential measurement technology is selected, and the potential parameter is set to -1.4V. Simultaneously, the carbon dioxide storage cylinder and gas flow controller are turned on, and the gas flow rate is set to 7 sccm. One-dimensional data is acquired using conventional pressurized water sequence methods and spatial selection sequence methods. 1 All H NMR spectra were performed on a Varian 500MHz spectrometer at an experimental temperature of 298K. The spectral width was set to 12ppm, and each spectrum was scanned 32 times. After the parameters were set, one-dimensional NMR data were acquired using both the conventional pressurized water sequence method and the spatially selected sequence method. 1 1H NMR spectrum. A potentiostatic measurement technique was initiated to induce an electroreduction reaction of carbon dioxide. After 3 hours, one-dimensional NMR spectra were acquired again using both conventional pressurized water sequence methods and spatially selected sequence methods. 1 1H NMR spectrum. One-dimensional NMR data acquired using conventional pressurized water sequence methods under aeration before the start of electroreduction. 1 The H NMR spectrum is shown in [reference]. Figure 2 Spectrum A in the image, a one-dimensional image acquired using the spatial selection sequence method under the same conditions. 1 The H NMR spectrum is shown in [reference]. Figure 2 Spectrum B in the image. One-dimensional data collected using conventional pressurized water sequence methods under aeration conditions after electroreduction of 3H. 1 The H NMR spectrum is shown in [reference]. Figure 3 Spectrum C in the image, a one-dimensional image acquired using the spatial selection sequence method under the same conditions. 1 The H NMR spectrum is shown in [reference]. Figure 3 Spectrum D in the image. Figure 3The local amplification spectrum of the middle chemical shift -0.3~2.0ppm is shown in the following figure Figure 4 . Figure 2 、 3 , the one-dimensional 1 H NMR spectrum obtained by the two data acquisition methods in 4 reflects that the use of spatial selection sequence method can resist the inhomogeneous field caused by the existence of gas medium and the like, so as to achieve the 1 H NMR spectrum with high resolution effect.

[0044] The specific embodiments of the present application are described above, but the protection scope of the present application is not limited thereto, any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A high-resolution nuclear magnetic resonance in-situ measurement device for carbon dioxide electro-reduction reaction, characterized in that, The device comprises an in-situ NMR tube, a fixed tube, an isolation tube, a gas tube, a three-electrode and a cap, the three-electrode comprises a counter electrode, a reference electrode and a working electrode, the working electrode is coated with a catalyst for carbon dioxide reduction reaction, the in-situ NMR tube comprises a first tube part and a second tube part with different diameters, the first tube part is arranged below the second tube part and is provided with a sample detection area of a nuclear magnetic resonance spectrometer, the working electrode and the gas tube are fixedly connected with the fixed tube and extend into the first tube part, only the working electrode of the three-electrode is partially located in the sample detection area, the counter electrode is fixedly installed in the isolation tube, an ion exchange membrane is fixedly wrapped at the bottom of the isolation tube, the reference electrode and the isolation tube are installed in the second tube part and are arranged in a spaced manner with the fixed tube, the gas tube is arranged in the interior of the fixed tube and is used for introducing carbon dioxide gas, the cap is covered on the top of the second tube part, an ion exchange solution for carbon dioxide reduction reaction is placed in the isolation tube and the liquid surface thereof covers at least the counter electrode, a reaction solution for carbon dioxide reduction reaction is placed in the in-situ NMR tube and the liquid surface thereof covers at least the reference electrode and the ion exchange membrane. 2.The high-resolution nuclear magnetic resonance in-situ measurement device for carbon dioxide electro-reduction reaction according to claim 1, characterized in that, The working electrode, the counter electrode and the reference electrode are connected with a first wire, a second wire and a third wire respectively, the first wire, the second wire and the third wire pass through holes in the cap and are connected with an electrochemical workstation. 3.The high-resolution nuclear magnetic resonance in-situ measurement device for carbon dioxide electro-reduction reaction according to claim 2, characterized in that, The first wire and the gas tube pass through the interior of the fixed tube in parallel and are fixedly connected at the bottom of the fixed tube. 4.The apparatus for in-situ measurement of high-resolution nuclear magnetic resonance for carbon dioxide electro-reduction reaction according to claim 1, wherein, The material of the working electrode comprises carbon fiber, the material of the reference electrode comprises silver wire and the material of the counter electrode comprises platinum wire. 5.The apparatus for in-situ measurement of high-resolution nuclear magnetic resonance for carbon dioxide electro-reduction reaction according to claim 1, wherein, A carbon dioxide gas storage bottle and a gas flow control meter are further included, the gas tube is connected with the gas flow control meter and the carbon dioxide gas storage bottle, and the flow of carbon dioxide in the gas tube is adjusted through the gas flow control meter. 6.The apparatus for in-situ measurement of high-resolution nuclear magnetic resonance for carbon dioxide electro-reduction reaction according to claim 1, wherein, The in-situ NMR tube is spliced from the first tube part and the second tube part, the diameter of the first tube part is 5 mm and the diameter of the second tube part is 10 mm.

7. The apparatus for in-situ measurement of high-resolution nuclear magnetic resonance for carbon dioxide electro-reduction reaction according to claim 1, characterized in that, The gas tube comprises a PTFE tube with a diameter of 0.3-1 mm, and the fixed tube and the isolation tube comprise glass tubes with an outer diameter of 3-4 mm and an inner diameter of 2-3.5 mm.

8. A high-resolution nuclear magnetic resonance in-situ measurement method for carbon dioxide electro-reduction reaction, characterized in that, The method comprises the following steps by using the high-resolution in-situ NMR measurement device for carbon dioxide reduction reaction according to any one of claims 1-7: Step 1) injecting a reaction solution for carbon dioxide reduction reaction into the in-situ NMR tube, assembling a three-electrode and a gas tube, inserting the three-electrode and the gas tube into the in-situ NMR tube after testing the passage, covering a cap on the in-situ NMR tube, connecting the three-electrode with an electrochemical workstation through a cable, turning on the electrochemical workstation, selecting electrochemical measurement software and related parameters, and delivering carbon dioxide into the in-situ NMR tube through the gas tube; Step 2) adjusting the gas flow rate and setting the sequence parameters for resisting the inhomogeneous field, starting the electrochemical workstation, performing the electrocatalytic reduction reaction of carbon dioxide, and collecting high-resolution nuclear magnetic resonance spectrum signals on a liquid-phase nuclear magnetic resonance spectrometer.

9. The high-resolution nuclear magnetic resonance in-situ measurement method for carbon dioxide electro-reduction reaction according to claim 8, characterized in that, The three-electrode and the gas tube are assembled in the step 1), specifically comprising: A catalyst for the carbon dioxide reduction reaction is coated on the working electrode and dried, the working electrode coated with the catalyst is connected with the first wire and passes through the inside of the fixed tube in parallel with the gas tube and is fixed at the lower end of the fixed tube; An ion exchange membrane is fixed at the lower end of the isolation tube, an ion exchange solution for the carbon dioxide electro-reduction reaction is injected into the isolation tube, the counter electrode is inserted into the ion exchange solution in the isolation tube, the counter electrode is fixed at the upper end of the isolation tube and connected with the second wire; The reference electrode is connected with the third wire.

10. The high-resolution nuclear magnetic resonance in-situ measurement method for carbon dioxide electro-reduction reaction according to claim 9, wherein, The sequence for resisting the inhomogeneous field includes a Spatially-Selective pulse sequence, and the parameters include the experimental temperature, the scanning times, the sampling time, the spectral width, and the selection pulse width.

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