An automated flow electrolytic cell for carbon dioxide electroreduction and its application

Abstract

The present invention discloses an automated flow electrolytic cell for carbon dioxide electroreduction, comprising a testing mechanism, a first moving mechanism, a pushing mechanism, a second moving mechanism and a control system; the testing mechanism comprises an electrolyte flow path system and a gas flow path chamber, the pushing mechanism comprises a supporting splint, a plurality of holes are arranged on the supporting splint, and the holes are used to place gas diffusion electrodes loaded with catalysts; the control system is used to control the movement of the first moving mechanism and the second moving mechanism so that gas diffusion electrodes with different holes are assembled between the electrolyte flow path system and the gas flow path chamber and sealed to form an electrolytic cell, and work in coordination with a preparation system, a detection system, etc., for automatic screening of catalysts for carbon dioxide electroreduction. The present invention solves the problem of manually installing and disassembling the reaction cell and replacing the electrode through the combined application of the pushing mechanism and the testing mechanism, thereby improving the test efficiency and reproducibility.

Description

Technical Field

[0001] The invention belongs to the field of automated controlled electrochemical testing, and in particular relates to a flow cell device for automated carbon dioxide electroreduction testing, which is used for screening electrocatalysts. Background Art

[0002] Carbon dioxide electroreduction is a current research hotspot because it can convert carbon dioxide into high-value chemicals at room temperature and pressure. The flow-type electrolytic cell based on gas diffusion electrodes can achieve a high carbon dioxide conversion efficiency. Its main components include anode and cathode electrolyte flow chambers, gas flow chambers, gas diffusion electrodes and ion conduction membranes.

[0003] Traditional flow-type electrolytic cells are composed of multiple detachable modules, which need to be manually assembled before testing. After each test, they need to be manually disassembled to replace the gas diffusion electrode for the next test. The test efficiency and flux are low. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides an automated flow electrolytic cell for carbon dioxide electroreduction and its application.

[0005] In order to achieve the above purpose, the technical solution of the present invention is:

[0006] An automated flow electrolytic cell for carbon dioxide electroreduction comprises a testing mechanism, a first moving mechanism, a pushing mechanism, a second moving mechanism and a control system; the testing mechanism comprises an electrolyte flow path system and a gas flow path chamber, the first moving mechanism is used to drive the gas flow path chamber to move relative to the electrolyte flow path system; the pushing mechanism comprises a supporting splint, a plurality of holes are arranged on the supporting splint, the holes are used to place gas diffusion electrodes loaded with catalysts, and the second moving mechanism is used to drive the supporting splint to move relative to the testing mechanism; the control system is used to control the movement of the first moving mechanism and the second moving mechanism so that the gas diffusion electrodes with different holes are assembled between the electrolyte flow path system and the gas flow path chamber and sealed to form an electrolytic cell, wherein the gas diffusion electrode serves as the cathode of the electrolytic cell.

[0007] Optionally, the electrolyte flow system includes a working electrode electrolyte flow chamber and a counter electrode electrolyte flow chamber, the working electrode electrolyte flow chamber is equipped with a reference electrode, the counter electrode electrolyte flow chamber is equipped with a counter electrode, and the gas diffusion electrode is assembled between the working electrode electrolyte flow chamber and the gas flow chamber.

[0008] Optionally, the surface of the electrolyte flow path system is also provided with a metal spring for an external circuit, and the support clamp is provided with a metal connector that is electrically connected to the gas diffusion electrode in each hole position one by one, and the metal connector is in contact and conductive with the metal spring when the corresponding gas diffusion electrode is assembled in the test structure.

[0009] Optionally, the first moving mechanism is a screw slide, the counter electrode electrolyte flow chamber is fixedly connected to the base of the screw slide, the working electrode electrolyte flow chamber is fixedly connected to the counter electrode electrolyte flow chamber, and the gas flow chamber is installed on the slider of the screw slide; the screw slide is driven by a stepper motor.

[0010] Optionally, the second moving mechanism is a screw slide, the pushing mechanism also includes a fixed base, the fixed base is mounted on a slider of the screw slide, and the supporting clamp is placed on the fixed base; the screw slide is driven by a stepper motor.

[0011] Optionally, the gas flow chamber, the working electrode electrolyte flow chamber and the counter electrode electrolyte flow chamber are respectively provided with matching through holes in the center, and fluid inlet and outlet pipes are respectively provided on both sides, wherein the outflow pipe of the gas flow chamber is used to connect to the gas phase analysis device, and the outflow pipe of the working electrode electrolyte flow chamber is used to connect to the liquid phase product collection module.

[0012] Optionally, it can be used in conjunction with an electrochemical workstation, a catalyst sample preparation system, and a product collection and detection system for automatic screening of catalysts for carbon dioxide electroreduction.

[0013] Optionally, the electrolyte flow path system and the gas flow path chamber are assembled on both sides of the gas diffusion electrode to construct closed electrolyte flow paths and reaction gas flow paths respectively, forming a gas-liquid-solid three-phase catalytic interface for electrolysis testing.

[0014] A method for testing electrocatalytic reduction of the above-mentioned automated flow electrolytic cell comprises the following steps:

[0015] 1) A gas diffusion electrode is attached to each hole of the supporting clamping plate, and a catalyst is coated on the gas diffusion electrode in sequence;

[0016] 2) Install the support clamp in the pushing mechanism, control the control system to control the second moving mechanism to drive the support clamp to move to a gas diffusion electrode at a hole position to align between the electrolyte flow path system and the gas flow path chamber, and control the first moving mechanism to drive the gas flow path chamber to move to press the support clamp, and seal and assemble to form an electrolytic cell;

[0017] 3) introducing electrolyte solution and gas raw material into the electrolyte flow path system and the gas flow path chamber respectively to perform electrolysis, and the gas phase product and liquid phase product enter the detection system respectively for detection;

[0018] 4) After the electrolysis is completed, the control system controls the first moving mechanism to drive the gas flow chamber to move to release the support clamp, and controls the second moving mechanism to drive the support clamp to move to the next hole position of the gas diffusion electrode to be assembled in the test mechanism for the next test.

[0019] Optionally, the second moving mechanism is further provided with a metal stopper, and when all the hole positions have completed the test, the supporting splint returns to the initial position through the metal stopper.

[0020] The beneficial effects of the present invention are:

[0021] 1. Compared with the traditional flow-type electrolytic cell device, the present invention abandons the traditional flow-type electrolytic cell that needs to be manually fastened and disassembled by screws, and completes the electrolysis by means of a mechanism setting to compress the gas diffusion electrode surface coated with the catalyst and the electrolyte solution surface, which has higher test efficiency;

[0022] 2. The porous structure is designed to automatically replace the catalyst and realize batch catalyst testing;

[0023] 3. Through the control system, the electrolysis test and catalyst replacement are automated, with high stability and reproducibility in test results. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Schematic diagram of an automated synthesis and catalyst coating module according to an embodiment of the present invention;

[0025] Figure 2 A schematic diagram of the overall process of automated testing and detection according to an embodiment of the present invention;

[0026] Figure 3 This is a schematic diagram of the overall structure of an automated flow electrolytic cell for carbon dioxide electroreduction according to an embodiment of the present invention;

[0027] Figure 4 An exploded diagram of a test mechanism according to an embodiment of the present invention;

[0028] Figure 5 An exploded view of a driving mechanism according to an embodiment of the present invention;

[0029] Figure 6 A schematic diagram of the cooperation between the test structure and the driving mechanism of an embodiment of the present invention;

[0030] Figure 7 for Figure 6 Enlarged view of part A.

[0031] Description of reference numerals:

[0032] Figure 1 Middle: A-catalyst synthesis module; B-catalyst coating module; A01-synthesis injection pump; B01-coating injection pump;

[0033] Figure 2Middle: 100-test mechanism; 200-propelling mechanism; 300-test mechanism screw slide (as the first moving mechanism); 400-propelling mechanism screw slide (as the second moving mechanism); 500-six-axis robotic arm; 600-gas chromatograph; 700-liquid product collection module; 800-counter electrode flow path peristaltic pump; 900-working electrode flow path peristaltic pump;

[0034] Figure 4 Middle: 101-M6×12 hexagon socket screw × 4; 102-M3×20 hexagon socket screw × 4; 103-M4×10 hexagon socket screw × 4; 104-M4×10 hexagon socket screw × 2; 105-support base; 106-M3×16 hexagon socket screw × 4; 107-counter electrode electrolyte flow chamber; 108-working electrode electrolyte flow chamber; 109-M3 hexagon nut × 4; 110-gas flow chamber; 111-support plate; 112-M4×10 hexagon socket screw × 4; 113-M3×25 hexagon socket screw × 4;

[0035] Figure 5 Middle: 201-supporting splint; 202-fixed base; 203-copper sheet metal (as metal connector); 204-M4×10 hexagon socket screw × 4;

[0036] Figure 7 Chinese: 114-Metal shrapnel. DETAILED DESCRIPTION

[0037] The present invention is further explained below in conjunction with the accompanying drawings and specific embodiments. The various drawings of the present invention are only for illustration to make it easier to understand the present invention, and the specific proportions can be adjusted according to design requirements. The upper and lower relationships of the relative elements and the definitions of the front / back in the figures described in the text should be understood by those skilled in the art to refer to the relative positions of the components, so they can all be flipped to present the same components, which should all fall within the scope disclosed in this specification.

[0038] The automated flow electrolysis cell for carbon dioxide electroreduction of the embodiment is Figure 1 and Figure 2 Based on the two processes in series, as the core test module of the entire automated process, it is controlled by a computer program and works in conjunction with the electrochemical workstation, automated catalyst sample preparation system, and product collection and detection system to complete the automatic screening of catalysts for carbon dioxide electroreduction. Figure 3 The automated flow electrolysis cell for carbon dioxide electroreduction of the embodiment includes a testing mechanism 100, a pushing mechanism 200, a testing mechanism lead screw slide 300 as a first moving mechanism, and a pushing mechanism lead screw slide 400 as a second moving mechanism, and also includes a control system for controlling the actions of the above mechanisms.

[0039] Combination Figure 3 and Figure 4 The test mechanism 100 is fixed as a whole on the test mechanism screw slide 300, the support base 105 is fastened to the left end, the base and the outer side of the test mechanism screw slide 300 by M6×12 hexagon socket screws 101, M4×10 hexagon socket screws 103 and M4×10 hexagon socket screws 104, the counter electrode electrolyte flow path chamber 107 is fastened to the support base 105 by M3×20 hexagon socket screws 102, the working electrode electrolyte flow path chamber 108 is fastened to the counter electrode electrolyte flow path chamber 107 by M3×16 hexagon socket screws 106 and M3 hexagon nuts 109, the gas flow path chamber 110 is fastened to the fixing part 111 by M3×25 hexagon socket screws 113, and the fixing part 105 is installed on the slider of the test mechanism screw slide 300 by M4×10 hexagon socket screws 112. The center of the three flow chambers is provided with a through hole of 10mm*10mm, and the two sides are provided with fluid circulation pipelines with an outer diameter of 4mm and an inner diameter of 2mm. The top of the working electrode electrolyte flow chamber 108 is provided with a through hole of 5mm in diameter for installing the reference electrode, and the top of the counter electrode electrolyte flow chamber 107 is provided with a through hole of 5mm in diameter for installing the foam nickel counter electrode. The testing organization mainly uses economical 3D printing photosensitive resin materials, which have good alkali resistance, acid resistance, high strength, and can obtain high-precision and high-surface quality components through 3D printing technology.

[0040] Combination Figure 3 and Figure 5 The pushing mechanism 200 is fixed on the slider of the pushing mechanism screw slide 400 as a whole, and the supporting clamp 201 is placed on the fixed base 202. There are several holes for placing gas diffusion electrodes, and each hole has a through hole on one side. The copper sheet metal 203 as a metal connector is inserted into the through hole of the supporting clamp 201. The fixed base 202 is installed on the slider of the pushing mechanism screw slide 400 through the M4×10 hexagon socket screw 204. The pushing mechanism screw slide 400 is also provided with a metal stopper, which is fixed on the side of the screw slide to provide a zero point limit. The pushing mechanism aligns the gas diffusion electrode sheets with different holes with the electrolytic cell to achieve catalyst replacement and batch testing.

[0041] The control system includes an Arduino UNO R3 control board and a stepper motor driver. The test mechanism screw slide 300 and the push mechanism screw slide 400 are driven by stepper motors respectively. When the device is working, the execution stepper motors of the screw slides of the test mechanism 100 and the push mechanism 200 are connected to the driver, and the driver is connected to the Arduino UNO R3 control board. The LabVIEW program on the PC sends pulse signals to control the stepper motor and drive the screw slide to move.

[0042] The gas flow chamber 110 is driven by the test mechanism screw slide 300 to move closer to or away from the working electrode electrolyte flow chamber 108, and the support clamp 201 is driven by the push mechanism screw slide 400 to move to different holes and assembled between the working electrode electrolyte flow chamber 108 and the gas flow chamber 110 and sealed to form an electrolytic cell. Preferably, the moving direction of the gas flow chamber 110 is perpendicular to the moving direction of the support clamp 201 to achieve better clamping and sealing and sequential replacement effects. The gas diffusion electrode is used as the test cathode. Reference Figure 6 and Figure 7 The metal spring 114 is embedded in the groove on the bottom upper surface of the electrode electrolyte flow path chamber 107, and the contact between the metal spring 114 and the copper sheet metal 203 is used to complete the conduction between the electrochemical workstation and the gas diffusion electrode.

[0043] The catalyst is prepared by a separate automated preparation system. The catalyst is loaded on the gas diffusion electrode by the automated system through drop coating. Figure 1 The catalyst synthesis module A completes the automated synthesis of the catalyst, and the catalyst coating module B automatically coats the catalyst on the upper surface of a gas diffusion electrode adhered to each through-hole position of the support clamp 201. After the coating is completed, the six-axis robot arm 500 removes the support clamp 201 from the Figure 1 Example location clamped to Figure 2 Example location.

[0044] refer to Figures 3 to 7 During the test preparation, a copper sheet metal 203 is inserted into the through hole opened at 5mm to the left of the loading hole of each catalyst on the support splint 201, and the customized expanded polytetrafluoroethylene material is adhered to the side of the support splint 201. The catalyst is coated on the surface of the 15*20mm gas diffusion electrode, and the gas diffusion electrode is adhered to the customized expanded polytetrafluoroethylene material using conductive glue. The conductive glue is wrapped around the top of the copper sheet metal 203. At this time, the copper sheet metal 203 serves as a conductive part for the working electrode of the electrochemical workstation and the conductive glue on the catalyst surface. During the test, the 10*10mm through holes at the center of the three components of the working electrode electrolyte flow chamber 108, the gas flow chamber 110, and the support clamp 201 are aligned, and the screw slide moves to press the support clamp 201 to prevent gas and liquid leakage. At this time, the bottom of the corresponding copper strip sheet metal 203 on the support clamp 201 will contact the metal spring 114 fixed on the bottom upper surface of the counter electrode electrolyte flow chamber 107, completing the electrolysis process. Figure 2When electrolysis begins, the electrolyte solution is pumped into the counter electrode electrolyte flow path chamber 107 and the working electrode electrolyte flow path chamber 108 by the counter electrode flow path peristaltic pump 800 and the working electrode flow path peristaltic pump 900, and the gas raw material is passed into the gas flow path chamber 110. After the electrolysis is completed, the test mechanism screw slide 300 will release the support clamp 201, and the push mechanism screw slide 400 will start to move forward 40mm to the test hole position of the next catalyst to test the next catalyst. The liquid phase product and gas phase product generated by the test will flow out from the pipelines of the working electrode electrolyte flow path chamber 108 and the gas flow path chamber 110 respectively. The gas phase product is directly passed into the gas chromatograph 600 for automatic real-time product detection, and the liquid phase product is automatically collected by the liquid phase product collection module 700 for nuclear magnetic characterization. After the catalysts in all holes are tested, the slider of the push mechanism screw slide 400 will return to the initial position through the metal limiter, and the six-axis robot 500 will take away the supporting clamp 201 that has completed the test to prepare for the next batch of tests.

[0045] The system of the present invention can automatically replace the gas diffusion electrode loaded with the catalyst, and build a closed reaction gas flow path and electrolyte flow path on both sides of the electrode to form a gas, liquid and solid three-phase catalytic interface, and continuously and stably perform electrolysis testing. The present invention solves the problem that the current flow-type electrolytic cell as a test device requires manual installation and disassembly of the reaction cell and replacement of electrodes through the combined application of the driving mechanism and the testing mechanism. While improving the test efficiency and reproducibility, it can be used as a reaction core module to carry out automated electrocatalyst screening.

[0046] The above embodiments are only used to further illustrate an automated flow electrolysis cell and application for carbon dioxide electroreduction of the present invention, but the present invention is not limited to the embodiments. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention shall fall within the protection scope of the technical solution of the present invention.

Claims

1. An automated flow electrolytic cell for carbon dioxide electroreduction, characterized in that: The invention comprises a testing mechanism, a first moving mechanism, a pushing mechanism, a second moving mechanism and a control system; the testing mechanism comprises an electrolyte flow path system and a gas flow path chamber, the first moving mechanism is used to drive the gas flow path chamber to move relative to the electrolyte flow path system; the pushing mechanism comprises a supporting splint, a plurality of holes are arranged on the supporting splint, the holes are used to place the gas diffusion electrode loaded with catalyst, and the second moving mechanism is used to drive the supporting splint to move relative to the testing mechanism; the control system is used to control the movement of the first moving mechanism and the second moving mechanism so that the gas diffusion electrodes with different holes are assembled between the electrolyte flow path system and the gas flow path chamber and sealed to form an electrolytic cell, wherein the gas diffusion electrode serves as the cathode of the electrolytic cell; the electrolyte flow path system comprises a working electrode electrolyte flow path chamber and a counter electrode electrolyte flow path chamber, the working electrode The electrolyte flow path chamber is equipped with a reference electrode, the counter electrode electrolyte flow path chamber is equipped with a counter electrode, and the gas diffusion electrode is installed between the working electrode electrolyte flow path chamber and the gas flow path chamber; the surface of the electrolyte flow path system is also provided with a metal spring for an external circuit, and the supporting clamp is provided with a metal connector that is electrically connected to the gas diffusion electrodes at each hole position one by one, and the metal connector is in contact and conductive with the metal spring when the corresponding gas diffusion electrode is assembled in the test mechanism; the gas flow path chamber, the working electrode electrolyte flow path chamber and the counter electrode electrolyte flow path chamber are respectively provided with matching through holes in the center, and fluid inlet and outlet pipelines are respectively provided on both sides, wherein the outflow pipeline of the gas flow path chamber is used to connect to the gas phase analysis device, and the outflow pipeline of the working electrode electrolyte flow path chamber is used to connect to the liquid phase product collection module.

2. The automated flow electrolytic cell for carbon dioxide electroreduction according to claim 1, characterized in that: The first moving mechanism is a lead screw slide, the counter electrode electrolyte flow chamber is fixedly connected to the base of the lead screw slide, the working electrode electrolyte flow chamber is fixedly connected to the counter electrode electrolyte flow chamber, and the gas flow chamber is installed on the slider of the lead screw slide; the lead screw slide is driven by a stepper motor.

3. The automated flow electrolytic cell for carbon dioxide electroreduction according to claim 1, characterized in that: The second moving mechanism is a lead screw slide, and the pushing mechanism also includes a fixed base, which is mounted on a slider of the lead screw slide, and the supporting clamp is placed on the fixed base; the lead screw slide is driven by a stepper motor.

4. The automated flow electrolytic cell for carbon dioxide electroreduction according to claim 1, characterized in that: It is used in conjunction with an electrochemical workstation, catalyst sample preparation system, and product collection and detection system for automatic screening of catalysts for carbon dioxide electroreduction.

5. The automated flow electrolytic cell for carbon dioxide electroreduction according to claim 1, characterized in that: The electrolyte flow path system and the gas flow path chamber are assembled on both sides of the gas diffusion electrode to respectively construct a closed electrolyte flow path and a reaction gas flow path, forming a gas-liquid-solid three-phase catalytic interface for electrolysis testing.

6. An electrocatalytic reduction test method for an automated flow electrolytic cell for carbon dioxide electroreduction according to any one of claims 1 to 5, characterized in that: The following steps are involved: 1) A gas diffusion electrode is attached to each hole of the supporting clamp, and the catalyst is coated on the gas diffusion electrode in turn; 2) The support clamp is installed in the pushing mechanism, and the control system controls the second moving mechanism to drive the support clamp to move to a gas diffusion electrode at a hole position to align between the electrolyte flow path system and the gas flow path chamber, and controls the first moving mechanism to drive the gas flow path chamber to move to press the support clamp, and seal and assemble to form an electrolytic cell; 3) Electrolyte solution and gas raw material are introduced into the electrolyte flow path system and the gas flow path chamber respectively to perform electrolysis, and the gas phase product and liquid phase product enter the detection system for detection respectively; 4) After the electrolysis is completed, the control system controls the first moving mechanism to drive the gas flow chamber to move to release the support clamp, and controls the second moving mechanism to drive the support clamp to move to the next hole position of the gas diffusion electrode to be assembled in the test mechanism for the next test.

7. The electrocatalytic reduction test method according to claim 6, characterized in that: The second moving mechanism is also provided with a metal stopper. When all the holes are tested, the support clamp returns to the initial position through the metal stopper.

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