In-situ electrochemical electron paramagnetic resonance spectrum test assembly and detection method

Abstract

The invention relates to the technical field of free radical detection, and provides an in-situ electrochemical electron paramagnetic resonance spectrum test assembly and a detection method.The in-situ electrochemical electron paramagnetic resonance spectrum test assembly comprises a pool body and two electrodes, a containing cavity is formed in the pool body, and the containing cavity is used for containing a mixed solution to be detected. And the cell body is provided with a liquid injection hole and two electrode holes which are communicated with the accommodating cavity and the outside. The two electrodes are inserted into the containing cavity, one part of one electrode extends out of the cell body through one electrode hole, and one part of the other electrode extends out of the cell body through the other electrode hole. According to the in-situ electrochemical electron paramagnetic resonance spectrum testing assembly, the electrodes are inserted into the accommodating cavities and extend out of the pool body through the corresponding electrode holes, so that the electrodes are connected with a power supply and electrify and electrolyze a mixed solution in the accommodating cavities, and the electrolysis requirement in the free radical detection process is met; the method can be simultaneously suitable for free radical detection processes without electrolysis or needing electrolysis, and is better in applicability.

Description

Technical Field

[0001] The invention relates to the technical field of free radical detection, and in particular to an in-situ electrochemical electron paramagnetic resonance spectroscopy test component and a detection method. Background Art

[0002] Electron paramagnetic resonance (EPR) technology is the only means to directly detect unpaired electrons. It has been widely used in the detection of free radicals, transition metal ions, etc. It plays a key role in chemistry, physics, biology, environment, food and other fields and is widely used.

[0003] When testing free radicals, the capillary method is usually used. The capillary method uses a 0.9 mm diameter capillary to absorb the test liquid, seals both ends with sealing mud, and then puts it into a quartz glass tube for testing. The capillary method has the advantage of low cost, but due to the limited load of a single capillary, the test sensitivity is insufficient and the detection limit is high. At the same time, the space inside the capillary is limited, making it difficult to perform in-situ testing.

[0004] At present, the development of clean energy is an important development direction of energy utilization. Among them, chemical reactions driven by electrical energy have received extensive attention and research. Free radicals are key intermediates in electrochemical synthesis. Revealing their structure and transformation characteristics will provide important support for mechanism research and reaction design. In-situ electrochemical EPR testing is an important means to study free radicals. At present, there is no in-situ reaction cell that is compatible and easy to use for in-situ electrochemical EPR testing, which greatly limits the popularization and application of this technology. Summary of the invention

[0005] The invention provides an in-situ electrochemical electron paramagnetic resonance spectroscopy test component and a detection method, which are used to solve the defect of the prior art that there is a lack of an in-situ reaction cell that can be applied to in-situ electrochemical EPR testing.

[0006] In a first aspect, the present invention provides an in-situ electrochemical electron paramagnetic resonance spectroscopy test assembly, comprising: A cell body, wherein a containing cavity is provided in the cell body, and the containing cavity is used to contain the mixed solution to be detected; the cell body is provided with a liquid injection hole and two electrode holes connecting the containing cavity and the outside; Two electrodes are inserted into the accommodating cavity, a portion of one of the electrodes extends out of the cell body through one of the electrode holes, and a portion of the other electrode extends out of the cell body through another of the electrode holes.

[0007] The in-situ electrochemical electron paramagnetic resonance spectroscopy test assembly provided by the present invention further includes a stopper rod; The plug rod is detachably mounted on the first end of the cell body.

[0008] According to the in-situ electrochemical electron paramagnetic resonance spectroscopy test assembly provided by the present invention, electrode grooves are provided on the side walls on the opposite sides of the accommodating cavity, and the two electrodes are respectively inserted into the two electrode grooves; The two electrode holes are both located at the first end of the cell body, and a wire groove is provided on the outer wall of the plug rod at a position corresponding to the electrode hole, and the wire groove is connected to the corresponding electrode hole.

[0009] According to the in-situ electrochemical electron paramagnetic resonance spectroscopy test assembly provided by the present invention, the first end of the cell body is provided with a protruding connection portion, the plug rod is provided with a connection hole corresponding to the connection portion, and the connection portion is plugged into the connection hole. Preferably, the plugging method is a threaded connection.

[0010] According to the in-situ electrochemical electron paramagnetic resonance spectroscopy test assembly provided by the present invention, the cell body is preferably manufactured by 3D printing.

[0011] According to the in-situ electrochemical electron paramagnetic resonance spectroscopy test assembly provided by the present invention, the connecting portion is provided with a first cleaning hole connecting the accommodating cavity and the outside, and the second end of the cell body is provided with a second cleaning hole connecting the accommodating cavity and the outside; a sealing member is arranged in the second cleaning hole.

[0012] According to the in-situ electrochemical electron paramagnetic resonance spectroscopy test component provided by the present invention, the accommodating cavity includes a first cavity and a second cavity which are interconnected, the second cavity is located at one end of the first cavity, the first cavity is in the shape of a rectangular parallelepiped, the cross-sectional area of ​​the second cavity gradually increases from one end facing the first cavity to one end facing away from the first cavity, and the injection hole is arranged on the side wall of the second cavity.

[0013] According to the in-situ electrochemical electron paramagnetic resonance spectroscopy test assembly provided by the present invention, the thickness of the first cavity is less than or equal to 3 mm.

[0014] According to the in-situ electrochemical electron paramagnetic resonance spectroscopy test assembly provided by the present invention, the cell body is a cylindrical cell body, and the side walls of the cylindrical cell body include two plane walls and two arcuate walls, the two plane walls are arranged in parallel and opposite to each other, the two ends of one of the arcuate walls are respectively connected to one end of the two plane walls, and the two ends of the other arcuate wall are respectively connected to the other end of the two plane walls, and the axis of the two arcuate walls is the central axis of the cylindrical cell body.

[0015] In a second aspect, the present invention further provides a detection method based on any one of the above-mentioned in-situ electrochemical electron paramagnetic resonance spectroscopy test components, comprising: Preparing a mixed solution to be detected, and injecting the mixed solution to be detected into the containing cavity of the cell body; The two electrodes are connected to the positive and negative electrodes of a power source respectively, and the mixed solution in the containing chamber is tuned and sampled without power supply to obtain a background signal spectrum; The mixed solution in the containing chamber is electrolyzed, and the electrolyzed mixed solution is tuned and sampled to obtain a detection spectrum.

[0016] The in-situ electrochemical electron paramagnetic resonance spectroscopy test component of the present invention is provided with a containing cavity and a liquid injection cavity connecting the containing cavity with the outside on the cell body so as to inject a mixed solution to be detected into the containing cavity and perform subsequent free radical detection; at the same time, by inserting electrodes in the containing cavity, the electrodes extend to the outside of the cell body through corresponding electrode holes so as to be connected to a power source and perform electrolysis on the mixed solution in the containing cavity so as to meet the electrolysis requirements in the free radical detection process, so that the in-situ electrochemical electron paramagnetic resonance spectroscopy test component of the present application can be simultaneously applicable to free radical detection processes that do not require electrolysis or require electrolysis, has better applicability, and effectively solves the defect of the prior art that there is a lack of in-situ reaction cells that can be applied to in-situ electrochemical EPR testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 This is one of the schematic diagrams of the in-situ electrochemical electron paramagnetic resonance spectroscopy test assembly provided in an embodiment of the present invention.

[0019] Figure 2 It is one of the schematic diagrams of the cell body provided in the embodiment of the present invention.

[0020] Figure 3 This is the second schematic diagram of the cell body provided in the embodiment of the present invention.

[0021] Figure 4 This is the second schematic diagram of the in-situ electrochemical electron paramagnetic resonance spectroscopy test assembly provided in an embodiment of the present invention.

[0022] Figure 5 Schematic diagram of a plug rod provided in an embodiment of the present invention.

[0023] Figure 6 It is one of the schematic diagrams of a cell body provided in another embodiment of the present invention.

[0024] Figure 7 This is the second schematic diagram of a cell body provided by another embodiment of the present invention.

[0025] Figure 8 This is the third schematic diagram of a cell body provided by another embodiment of the present invention.

[0026] Fig. 9 yes Figure 8 Cross-sectional view at point A.

[0027] Fig.10 This is the detection spectrum of test example 1 provided by the present invention.

[0028] Fig.11 This is the detection spectrum of test example 2 provided by the present invention.

[0029] Fig.12 It is a detection spectrum of the detection method provided by an embodiment of the present invention.

[0030] Fig.13 This is the background signal spectrum of test example 3 provided by the present invention.

[0031] Fig.14 This is the detection spectrum of test example three provided by the present invention.

[0032] Fig.15 This is the background signal spectrum of test example 4 provided by the present invention.

[0033] Fig.16 This is the detection spectrum of test example 4 provided by the present invention.

[0034] Fig.17 This is the background signal spectrum of test example 5 provided by the present invention.

[0035] Fig.18 This is the detection spectrum of Test Example 5 provided by the present invention.

[0036] Reference numerals: 1. Cell body; 11. Accommodating cavity; 111. Electrode slot; 112. First cavity; 113. Second cavity; 12. Liquid injection hole; 13. Electrode hole; 14. Connecting part; 15. First cleaning hole; 16. Second cleaning hole; 2. Electrode; 3. Plug rod; 31. Wire guide groove. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] Combine the following Figure 1-Figure 9 The in situ electrochemical electron paramagnetic resonance spectroscopy test assembly of the present invention is described.

[0039] like Figures 1 to 3 As shown, the present invention provides an in-situ electrochemical electron paramagnetic resonance spectroscopy test assembly, comprising: a cell body 1 and two electrodes 2, wherein a receiving chamber 11 is provided in the cell body 1, and the receiving chamber 11 is used to receive a mixed solution to be detected. The cell body 1 is provided with a liquid injection hole 12 and two electrode holes 13 that communicate the receiving chamber 11 with the outside. The two electrodes 2 are inserted into the receiving chamber 11, wherein a portion of one electrode 2 extends out of the cell body 1 through one electrode hole 13, and a portion of the other electrode 2 extends out of the cell body 1 through the other electrode hole 13.

[0040] In this embodiment, a accommodating chamber 11 is provided in the cell body 1, and an injection hole 12 connecting the accommodating chamber 11 and the outside is provided on the cell body 1, so that the detection personnel can prepare the mixed solution to be detected, inject the mixed solution into the accommodating chamber 11 from the injection hole 12, and place the cell body 1 containing the mixed solution in the resonant cavity of the electron paramagnetic resonance spectrometer for tuning and sampling, so as to detect free radicals in the mixed solution.

[0041] At the same time, by inserting two electrodes 2 in the cell body 1 and providing electrode holes 13 corresponding to the electrodes 2 on the cell body 2, the electrodes 2 can extend from the corresponding electrode holes 13 to the outside of the cell body 1 so as to be connected to the positive and negative poles of an external power supply, so as to energize and electrolyze the solution in the accommodating cavity 11 to meet the electrolysis requirements in the process of detecting free radicals.

[0042] It is understandable that when the test process does not require electrolysis, the electrode 2 may not be electrically connected to the power supply, and only the cell body 1 itself may be used to contain the mixed solution to be tested.

[0043] The in-situ electrochemical electron paramagnetic resonance spectroscopy test component of the present invention is provided with a accommodating chamber 11 and a liquid injection chamber connecting the accommodating chamber 11 with the outside on the cell body 1, so as to inject a mixed solution to be detected into the accommodating chamber 11 and perform subsequent free radical detection; at the same time, by inserting an electrode 2 in the accommodating chamber 11, the electrode 2 extends to the outside of the cell body 1 through a corresponding electrode hole 13, so as to be connected to a power source and electrolyze the mixed solution in the accommodating chamber 11, so as to meet the electrolysis requirements in the free radical detection process, so that the in-situ electrochemical electron paramagnetic resonance spectroscopy test component of the present application can be applied to free radical detection processes that do not require electrolysis or require electrolysis, has better applicability, and effectively solves the defect of the prior art that there is a lack of in-situ reaction cells that can be applied to in-situ electrochemical EPR testing.

[0044] In some embodiments, Figure 4 and Figure 5 As shown, the in-situ electrochemical electron paramagnetic resonance spectroscopy test assembly further includes a stopper rod 3 ; the stopper rod 3 is detachably mounted on the first end of the cell body 1 .

[0045] In this embodiment, the plug rod 3 is installed at the first end of the cell body 1, so that the plug rod 3 can be conveniently held by the inspector. It is understandable that the cell body 1 is usually small in size and is not convenient for the inspector to hold it directly. At the same time, in some inspection processes, the cell body 1 needs to be processed at a specific temperature (such as extremely low temperature). In these inspection processes, the inspector can hold the plug rod 3 to move the cell body 1, which is more convenient and safe.

[0046] In some embodiments, Figure 1 and Figure 4 As shown, electrode grooves 111 are provided on the side walls of the accommodating chamber 11 on opposite sides, and the two electrodes 2 are respectively inserted into the two electrode grooves 111. The two electrode holes 13 are both located at the first end of the cell body 1, and the outer wall of the plug rod 3 is provided with a wire groove 31 at the position corresponding to the electrode hole 13, and the wire groove 31 is connected to the corresponding electrode hole 13.

[0047] In this embodiment, two electrode slots 111 are provided on the side wall of the accommodating chamber 11, and the electrodes 2 are plugged into the electrode slots 111 one by one, so as to limit the position of the two electrodes 2 and avoid the electrodes 2 from crossing or contacting each other, so as to electrolyze the mixed solution in the accommodating chamber 11. At the same time, by providing the electrode hole 13 at the first end of the cell body 1 on which the plug rod 3 is installed, the wire groove 31 on the outer wall of the plug rod 3 is connected to the electrode hole 13, so that after the electrode 2 is connected to the external wire, the external wire is placed in the wire groove 31, the external wire is limited and fixed, and the wire is prevented from being entangled and knotted, which is convenient for operation, and can also prevent the electrode 2 from touching the external conductor to affect the detection result.

[0048] Optionally, in some embodiments, the bottom of the accommodating cavity 11 is provided with limiting holes corresponding to the positions of the two electrode grooves 111 and connected to the electrode grooves 111 , and one end of the electrode 2 is inserted into the corresponding limiting hole.

[0049] In a specific embodiment, Figure 4 and Figure 5 As shown, the plug rod 3 includes a first rod body, a second rod body and a third rod body connected in sequence, and the cross-sectional areas of the first rod body, the second rod body and the third rod body are increased in sequence to form a stepped rod body. The first rod body is connected to the cell body 1, and a wire groove 31 is provided on the outer wall of the first rod body. The second rod body and the third rod body are provided with through wire holes, and the opening at one end of the wire hole is connected to the wire groove 31, and the opening at the other end is located at the end face of the third rod body away from the first rod body, so that the external wire can be laid along the wire groove 31 and the wire hole, and extend from the opening at the end face of the third rod body to connect with the power supply. The first rod body is inserted into the resonant cavity of the electron paramagnetic resonance spectrometer so that the cell body 1 enters the resonant cavity, and the second rod body is hollowly sleeved at the entrance of the resonant cavity of the electron paramagnetic resonance spectrometer so that the cell body 1 is fixed at the center position of the resonant cavity of the electron paramagnetic resonance spectrometer, and the step between the third rod body and the second rod body abuts against the plane at the entrance of the resonant cavity of the electron paramagnetic resonance spectrometer so as to fix the axial position of the cell body 1.

[0050] In some embodiments, Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, a connecting portion 14 is protruding from the first end of the cell body 1, and a connecting hole is provided at the plug rod 3 corresponding to the connecting portion 14, and the connecting portion 14 is plugged into the connecting hole.

[0051] In this embodiment, by respectively providing a connecting portion 14 and a connecting hole on the cell body 1 and the plug rod 3, the connecting portion 14 and the connecting hole can be plugged into each other so as to install the plug rod 3 on the cell body 1. Optionally, an external thread can be provided on the outer wall of the connecting portion 14, and an internal thread matched with the external thread can be provided on the inner wall of the connecting hole. The connecting portion 14 and the connecting hole can be connected and fixed by the external thread and the internal thread, and the structure is simple and easy to disassemble and assemble.

[0052] Specifically, in some embodiments, the cell body 1 is a 3D printed part. In this embodiment, the cell body 1 can be made by photocuring 3D printing. Specifically, the cell body 1 is formed by polymerizing the prepolymer layer by layer during the 3D printing process. The printed cell body 1 has high strength, hardness and chemical stability, and is conducive to improving the production efficiency of the cell body 1 and reducing the production cost of the cell body 1.

[0053] Specifically, when performing photocuring 3D printing, the cell body 1 is placed horizontally. Specifically, the length direction of the cell body 1 is along the horizontal direction, and a support is placed below the corresponding connection part 14 to keep the connection part 14 stable during printing, and to prevent the connection part 14 from tilting downward due to gravity during printing, thereby reducing the printing height and improving the printing efficiency. The support is removed after printing is completed.

[0054] Specifically, the pool body 1 is printed with polyurethane material.

[0055] Furthermore, in some embodiments, Figure 1 , Figure 2 and Figure 3 As shown, the connecting portion 14 is provided with a first cleaning hole 15 connecting the accommodating chamber 11 and the outside, and the second end of the cell body 1 is provided with a second cleaning hole 16 connecting the accommodating chamber 11 and the outside. A blocking member is provided in the second cleaning hole 16.

[0056] In this embodiment, by providing a first cleaning hole 15 at the connection portion 14 and a second cleaning hole 16 at the second end of the cell body 1, when free radical detection is completed, a cleaning agent can be injected into the accommodating chamber 11 through the first cleaning hole 15 and the second cleaning hole 16 to clean the accommodating chamber 11. At the same time, the first cleaning hole 15 is located at the connection portion 14, and after the plug rod 3 is installed, the plug rod 3 can directly block the first cleaning hole 15, and a blocking member is provided in the second cleaning hole 16 to block the second cleaning hole 16, which is beneficial to improve the airtightness of the accommodating chamber 11, so as to conduct free radical detection experiments.

[0057] At the same time, when the pool body 1 is 3D printed by photocuring, after the photocuring 3D printing is completed, a cleaning agent can also be injected into the accommodating cavity 11 through the first cleaning hole 15 and the second cleaning hole 16 to clean the uncured prepolymer remaining in the inner cavity due to the 3D printing process.

[0058] In some embodiments, the accommodating cavity 11 includes a first cavity 112 and a second cavity 113 that are interconnected. The second cavity 113 is located at one end of the first cavity 112. The first cavity 112 is in the shape of a rectangular parallelepiped. The cross-sectional area of ​​the second cavity 113 gradually increases from one end facing the first cavity 112 to the end facing away from the first cavity 112. The injection hole 12 is arranged on the side wall of the second cavity 113.

[0059] In this embodiment, the accommodating cavity 11 is divided into a first cavity 112 and a second cavity 113 which are interconnected, and the second cavity 113 is gradually expanded from one end toward the other end of the first cavity 112, and the cross-sectional area gradually increases, so that it is convenient to set the injection hole 12 and inject liquid, and the cross-sectional area of ​​the first cavity 112 is made smaller, so that the first cavity 112 forms a rectangular cavity with a relatively thin thickness, and the thickness of the mixed solution in the first cavity 112 is relatively thin, so as to avoid the absorption of microwaves by the mixed solution affecting the tuning sampling results of the electron paramagnetic resonance spectrometer.

[0060] Specifically, the second cavity 113 is located at the first end of the cell body 1 and communicates with the first cleaning hole 15 of the connecting portion 14 ; the first cavity 112 extends to the second end of the cell body 1 and communicates with the second cleaning hole 16 .

[0061] Specifically, in some embodiments, the thickness of the first cavity 112 is less than or equal to 3 mm. In this embodiment, by limiting the thickness of the first cavity 112 to be less than or equal to 3 mm, the thickness of the mixed solution in the first cavity 112 is prevented from being too large, thereby affecting the tuning sampling result of the electron paramagnetic resonance spectrometer.

[0062] Preferably, in some embodiments, the thickness of the first cavity 112 is greater than or equal to 0.1 mm and less than or equal to 1 mm. In this embodiment, by limiting the thickness of the first cavity 112 to between 0.1 mm and 1 mm, the first cavity 112 can accommodate as much mixed solution as possible to be detected while avoiding the mixed solution being too thick to affect the tuning sampling result of the electron paramagnetic resonance spectrometer.

[0063] In a specific embodiment, the size of the first cavity 112 is 62mm×10mm×0.5mm, and the effective volume of the first cavity 112 is 310μL. Generally speaking, the effective volume of a capillary with an inner diameter of 0.5mm is 12.2μL. It can be seen that the cell body 1 of this embodiment can accommodate more mixed liquids and has a better effect in detecting free radicals.

[0064] In another embodiment, if Figure 6 , Figure 7 , Figure 8 and Fig. 9 As shown, the pool body 1 is a cylindrical pool body, and the side walls of the cylindrical pool body include two plane walls and two curved walls. The two plane walls are arranged parallel to each other, and the two ends of one curved wall are respectively connected to one end of the two plane walls, and the two ends of the other curved wall are respectively connected to the other end of the two plane walls, and the axis of the two curved walls is the central axis of the cylindrical pool body.

[0065] In this embodiment, by setting the pool body 1 as a cylindrical pool body, the side wall of the cylindrical pool body is formed by two plane walls and a curved wall, the two plane walls are arranged in parallel, and the two curved walls are arranged at both ends of the two plane walls, so that the connection between the side walls of the cylindrical pool body is smoother, so as to facilitate 3D printing and production, and make the force at each position more uniform, so that the cold resistance of the cylindrical pool body is better, and it can have better structural stability under low temperature treatment, so that the application range of the pool body 1 is better.

[0066] Based on the above embodiments, this application provides two test examples.

[0067] Test example 1: Test process: Dissolve 0.2 mmol copper nitrate in 1 mL dimethylacetamide (DMA) reagent, and then dilute the mixed solution to 0.02M copper nitrate solution. Use a 1mL syringe to take 0.02M copper nitrate solution and inject it into the containing cavity 11 from the injection hole 12, with a total volume of about 207μL. Place the cell body 1 in the resonant cavity of the electron paramagnetic resonance spectrometer, purge it with liquid nitrogen to cool it to -193℃, then tune it, click the sampling button, and get the corresponding waveform spectrum.

[0068] The test results are as follows Fig.10 As can be seen, the peaks and valleys are very clear and the signal-to-noise ratio is high, allowing for qualitative analysis of the copper(II) species.

[0069] Test Example 2: Test process: 100 mg of carbon nitride (photocatalyst), 500 microliters of triethanolamine, and 2 mL of dimethyl sulfoxide (DMSO) reagent were fully mixed and ultrasonically dispersed. Use a 1 mL syringe to take the mixed solution and inject it into the containing cavity 11 from the injection hole 12, with a total volume of about 207 μL. Pre-irradiate the cell body 1 under a 300W full-spectrum xenon lamp for 1 minute, and then put it into the resonant cavity of the electron paramagnetic resonance spectrometer. Under the irradiation of the xenon lamp, it was cooled to -193 degrees by liquid nitrogen purge, and then tuned, and clicked the sampling button to obtain the corresponding waveform spectrum.

[0070] The test results are as follows Fig.11 As can be seen, the peaks and valleys are very clear and the signal-to-noise ratio is high, allowing for qualitative analysis of the free radical species.

[0071] On the other hand, the present invention also provides a detection method for an in-situ electrochemical electron paramagnetic resonance spectroscopy test component based on any of the above-mentioned embodiments. By adopting the in-situ electrochemical electron paramagnetic resonance spectroscopy test component of the above-mentioned embodiment, the detection method of the present invention also has the advantages of the above-mentioned in-situ electrochemical electron paramagnetic resonance spectroscopy test component, which will not be repeated here.

[0072] like Fig.12 As shown, the detection method comprises the following steps: Step S101: preparing a mixed solution to be detected, and injecting the mixed solution to be detected into the containing cavity of the cell body.

[0073] Step S102: connecting the two electrodes to the positive and negative electrodes of the power supply respectively, and performing tuning sampling on the mixed solution in the containing chamber without power supply to obtain a background signal spectrum; Step S103: electrolyzing the mixed solution in the accommodating chamber, and tuning and sampling the electrolyzed mixed solution to obtain a detection spectrum.

[0074] Before detection, it is first necessary to configure a mixed solution for detection. Specifically, the compound of the free radical to be detected and the electrolyte need to be dissolved in a solvent. Among them, the electrolyte is convenient for electrolysis in the subsequent process to improve the signal-to-noise ratio and signal intensity of the spectrum after tuning sampling. After the mixed solution is configured, the mixed solution can be injected into the accommodating cavity 11 of the cell body 1 by a tool such as a syringe.

[0075] Then, the two electrodes 2 are connected to the positive and negative poles of the power supply through external wires and inserted into the accommodating cavity 11. The two electrodes 2 serve as the cathode and anode of the electrolytic cell respectively. When the power is turned off and the cell body 1 is lowered into the resonant cavity of the electron paramagnetic resonance spectrometer, the background signal spectrum is measured.

[0076] After measuring the background signal spectrum, turn on the power supply, set the power supply parameters, and perform constant current electrolysis on the mixed solution. After power is turned on, the reactants in the solution can undergo single electron transfer on the cathode or anode surface to obtain free radical active species.

[0077] After the electrolysis is set for a certain time, tuning sampling is performed and a detected waveform spectrum is obtained. By comparing the background signal spectrum and the detected spectrum, a qualitative analysis of the free radicals in the mixed solution can be performed. After electrolysis, tuning sampling is performed again. The peaks and troughs of the obtained waveform spectrum are clearer and the signal-to-noise ratio is high, which is conducive to analysis based on the spectrum.

[0078] Based on the above-mentioned embodiments of the detection method, this application provides three test examples.

[0079] Test Example 3: Test process: Dissolve 0.1 mmol phenothiazine and 0.2 mmol tetra-n-butylammonium hexafluorophosphonate (electrolyte) in 1 mL acetonitrile. Insert two platinum wires (electrode 2) into the chamber 11 of the cell body 1, as the cathode and anode respectively. Use a 1 mL syringe to draw the mixed solution and inject it into the chamber 11 from the injection port 12, with a total volume of about 248 μL. Place the device in the resonant cavity of the electron paramagnetic resonance spectrometer, tune it, click the sampling button, and obtain the background signal spectrum (such as Fig.13 as shown).

[0080] Then, the two electrodes 2 are connected to an external power supply, the power supply current is set to 1 mA, and the mixed solution is energized for electrolysis. After electrolysis for 1 minute, the sample is tuned again to obtain a detection spectrum (such as Fig.14 as shown).

[0081] Test Example 4: Test process: Dissolve 0.1 mmol quinoxime and 0.2 mmol tetrabutylammonium hexafluorophosphonate (electrolyte) in 1 mL acetonitrile. Insert two platinum wires (electrode 2) into the chamber 11 of the cell body 1, as the cathode and anode respectively. Use a 1 mL syringe to draw the mixed solution and inject it into the chamber 11 from the injection port 12, with a total volume of about 248 μL. Place the device in the resonant cavity of the electron paramagnetic resonance spectrometer, tune it, click the sampling button, and obtain the background signal spectrum (such as Fig.15 as shown).

[0082] Then, the two electrodes 2 were connected to an external power supply, the power supply current was set to 10 mA, and the mixed solution was energized for electrolysis. After electrolysis for 3 minutes, the sample was tuned again to obtain a detection spectrum (such as Fig.16 as shown).

[0083] Test Example 5: Test process: Dissolve 0.1 mmol 9,10-anthraquinone and 0.2 mmol tetra-n-butylammonium hexafluorophosphonate (electrolyte) in 1 mL acetonitrile. Insert two platinum wires (electrode 2) into the chamber 11 of the cell body 1, as the cathode and anode respectively. Use a 1mL syringe to take the mixed solution and inject it into the chamber 11 from the injection port 12, with a total volume of about 248μL. Place the device in the resonant cavity of the electron paramagnetic resonance spectrometer, tune it, click the sampling button, and obtain the background signal spectrum (such as Fig.17 as shown).

[0084] Then, the two electrodes 2 were connected to an external power supply, the power supply current was set to 10 mA, and the mixed solution was energized for electrolysis. After electrolysis for 3 minutes, the sample was tuned again to obtain a detection spectrum (such as Fig.18 as shown).

[0085] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An in-situ electrochemical electron paramagnetic resonance spectroscopy test assembly, characterized in that: include: A cell body, wherein a containing cavity is provided in the cell body, and the containing cavity is used to contain the mixed solution to be detected; the cell body is provided with a liquid injection hole and two electrode holes communicating with the containing cavity and the outside; Two electrodes are inserted into the accommodating cavity, a portion of one of the electrodes extends out of the cell body through one of the electrode holes, and a portion of the other electrode extends out of the cell body through another of the electrode holes.

2. The in-situ electrochemical electron paramagnetic resonance spectroscopy test assembly according to claim 1, characterized in that: Also includes a plug rod; The plug rod is detachably mounted on the first end of the cell body.

3. The in-situ electrochemical electron paramagnetic resonance spectroscopy test assembly according to claim 2, characterized in that: Electrode grooves are provided on the side walls of the accommodating cavity on opposite sides, and the two electrodes are respectively inserted into the two electrode grooves; The two electrode holes are both located at the first end of the cell body, and a wire groove is provided on the outer wall of the plug rod at a position corresponding to the electrode hole, and the wire groove is connected to the corresponding electrode hole.

4. The in-situ electrochemical electron paramagnetic resonance spectroscopy test assembly according to claim 2, characterized in that: A connecting portion is protrudingly provided at the first end of the cell body, a connecting hole is provided on the plug rod corresponding to the connecting portion, and the connecting portion is plugged into the connecting hole.

5. The in-situ electrochemical electron paramagnetic resonance spectroscopy test assembly according to claim 1, characterized in that: The connecting portion is provided with a first cleaning hole communicating with the accommodating cavity and the outside, and the second end of the cell body is provided with a second cleaning hole communicating with the accommodating cavity and the outside; a blocking member is provided in the second cleaning hole.

6. The in-situ electrochemical electron paramagnetic resonance spectroscopy test assembly according to claim 1, characterized in that: The accommodating cavity includes a first cavity and a second cavity which are interconnected. The second cavity is located at one end of the first cavity. The first cavity is in a rectangular shape. The cross-sectional area of ​​the second cavity gradually increases from one end facing the first cavity to one end facing away from the first cavity. The injection hole is arranged on the side wall of the second cavity.

7. The in-situ electrochemical electron paramagnetic resonance spectroscopy test assembly according to claim 6, characterized in that: The thickness of the first cavity is less than or equal to 3 mm.

8. The in-situ electrochemical electron paramagnetic resonance spectroscopy test assembly according to claim 1, characterized in that: The pool body is a cylindrical pool body, and the side walls of the cylindrical pool body include two plane walls and two arc-shaped walls. The two plane walls are arranged parallel to each other, and the two ends of one of the arc-shaped walls are respectively connected to one end of the two plane walls, and the two ends of the other arc-shaped wall are respectively connected to the other end of the two plane walls, and the axis of the two arc-shaped walls is the central axis of the cylindrical pool body.

9. A detection method based on the in-situ electrochemical electron paramagnetic resonance spectroscopy test assembly according to any one of claims 1 to 8, characterized in that: include: Preparing a mixed solution to be detected, and injecting the mixed solution to be detected into the containing cavity of the cell body; The two electrodes are connected to the positive and negative electrodes of a power source respectively, and the mixed solution in the containing chamber is tuned and sampled without power supply to obtain a background signal spectrum; The mixed solution in the containing chamber is electrolyzed, and the electrolyzed mixed solution is tuned and sampled to obtain a detection spectrum.

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