A general-purpose covalently functionalized graphene electrolysis preparation device and method of use thereof

Abstract

The application belongs to the technical field of graphene material preparation, and particularly relates to a universal covalent functionalized graphene electrolytic preparation device and a use method thereof. Reactant graphite paper electrodes are installed on electrode mounting holes on an electrolytic cell cover of a four-channel electrolytic reaction tank mechanism through a conductive clamp mechanism, the graphite paper conductive clamp mechanism is clamped at the upper end of the graphite paper electrodes, the graphite paper electrodes extend into a main cavity of the electrolytic cell, four groups of liquid delivery systems of a working liquid delivery mechanism are connected to four liquid injection and discharge ports of the four-channel electrolytic reaction tank mechanism through working liquid pipelines, and the four-channel electrolytic reaction tank mechanism, the graphite paper electrode conductive clamp mechanism, the working liquid delivery mechanism and an electrical control mechanism are integrally installed on a shell and an installation integration mechanism. The effective combination of the application and the automatic control components enables the covalent functionalized graphene electrochemical preparation method to be automatically realized through program control.

Description

Technical Field

[0001] This invention belongs to the field of graphene material preparation technology, specifically a universal covalently functionalized graphene (CFG) electrolytic preparation device and its usage method. Using this device and workflow, CFG materials with different functionalization properties can be efficiently prepared by controlling the chemical composition of the electrolyte and the parameters of the electrochemical reaction process. Background Technology

[0002] CFG refers to graphene-like two-dimensional materials in which a large number of non-carbon atoms or organic functional groups are grafted onto or within the carbon plane of graphene through covalent bonding. The presence of these functional groups or doped atoms can endow graphene materials with more diverse functions, improve their dispersibility in solvents to facilitate their assembly into macroscopic application materials, and effectively perform their functions. Therefore, CFG is a key material form for graphene applications, and achieving its efficient and controlled preparation has significant application value.

[0003] Chinese invention patent application CN202311072987.3, entitled "A Universal Electrochemical Preparation Method for Covalently Functionalized Graphene," proposes a two-step microliquid membrane electrolysis technique for the efficient preparation of different types of covalently functionalized graphene. The core of this technique lies in achieving stable first-order intercalated graphite electrodes through oil sealing technology and in constructing and manipulating the microliquid membrane structure used for electrolysis. This preparation technique requires the injection or discharge of various working liquids into the electrolytic cell according to a specific procedure, and there are strict requirements for the synergy of the injection rates, making effective control difficult through manual methods. Summary of the Invention

[0004] The purpose of this invention is to provide a universal electrolytic preparation device for covalently functionalized graphene and its usage method. Through the structural and operational design of the preparation device and the effective combination of automated control components, the electrochemical preparation method for covalently functionalized graphene is automatically realized through program control.

[0005] The technical solution of this invention is:

[0006] A general-purpose covalently functionalized graphene electrolytic preparation device includes: a four-channel electrolytic reaction cell mechanism, a graphite paper electrode conductive clamp mechanism, a working fluid transport mechanism, an electrical control mechanism, and a housing and installation integration mechanism. The specific structure is as follows:

[0007] The graphite paper electrode conductive clamping mechanism is installed in the electrode mounting hole on the electrolytic cell cover of the four-channel electrolytic reaction cell mechanism. The graphite paper electrode conductive clamping mechanism clamps the upper end of the graphite paper electrode, which extends into the inner cavity of the electrolytic cell body. The four sets of liquid delivery systems of the working liquid delivery mechanism are connected to the four injection and discharge ports of the four-channel electrolytic reaction cell mechanism through the working liquid pipeline. The four-channel electrolytic reaction cell mechanism, the anode graphite paper conductive clamping mechanism, the working liquid delivery mechanism, and the electrical control mechanism are integrated and installed in the housing and the integrated installation mechanism.

[0008] The aforementioned universal covalent functionalized graphene electrolytic preparation device comprises an integrated four-channel electrolytic reactor body and a multifunctional electrolytic reactor cover. The integrated four-channel electrolytic reactor body is cylindrical with an open top for mounting the reactor cover. It has four liquid passage openings on the side walls and bottom: 1# injection / drainage port, 2# injection / drainage port, 3# injection / drainage port, and 4# injection / drainage port. A hole is located on the side wall near the upper edge of the electrolytic reactor body, connected to a single-hole inlet / drainage pipe. The outer end of the single-hole inlet / drainage pipe is the 1# injection / drainage port. The bottom of the electrolytic reactor body uses a hemispherical end cap. A hole is located at the very bottom of the electrolytic reactor body and connected to a pipe connector. The pipe joint includes a vertical inlet / outlet pipe and two horizontal inlet / outlet pipes. The horizontal inlet / outlet pipes are arranged parallel to each other and are vertically connected to the vertical inlet / outlet pipe. The outer ports of the upper and lower horizontal inlet / outlet pipes are respectively the No. 2 inlet / outlet port and the No. 3 inlet / outlet port. The lower port of the vertical inlet / outlet pipe is the No. 4 inlet / outlet port. The uppermost opening of the pipe joint is connected to the main body of the electrolytic cell. The multifunctional electrolytic cell cover is equipped with cathode rods and insulating partitions, and supports the anode graphite paper conductive clamp mechanism. The top of the electrolytic cell cover is provided with two cathode rod mounting holes, two partition mounting holes, two or more cell cover vent holes, and an anode mounting hole that matches the shape of the anode graphite paper conductive clamp mechanism.

[0009] The aforementioned universal covalent functionalized graphene electrolytic preparation device has a lower level gauge and an upper level gauge installed on the side wall of the electrolytic cell body to sense the starting position and ending position of the micro-liquid film. The lower and upper level gauges are resistive or capacitive level sensors. The electrolytic cell body is made of glass, quartz, ceramic, metal or plastic.

[0010] The aforementioned universal covalent functionalized graphene electrolytic preparation device uses an inert conductive material for the cathode rod. The length of the cathode rod ensures that it can contact the bottom of the inner cavity of the electrolytic cell body, and a certain wiring length is reserved above the electrolytic cell cover for connection with the power supply electrode.

[0011] The aforementioned universal covalent functionalized graphene electrolytic preparation device includes an anode graphite paper conductive clamp mechanism comprising two conductive clamping plates with threaded holes. The anode graphite paper is clamped between the two conductive clamping plates and secured by clamping screws through the threaded holes, ensuring the conductive clamping plates tightly hold the anode graphite paper. Terminals are provided on the upper part of the two conductive clamping plates for connection to the positive terminal of the power supply via wires. The upper part of the anode graphite paper, where it connects to the conductive clamping plates, corresponds to the oil seal area of ​​the electrolytic cell, while the remaining anode graphite paper corresponds to the reaction area of ​​the electrolytic cell.

[0012] The aforementioned universal covalent functionalized graphene electrolytic preparation device includes a working fluid transport mechanism comprising four sets of delivery systems, each consisting of a working fluid storage tank, a peristaltic pump, a bidirectional solenoid valve, and a working fluid pipeline. Each delivery system is connected to the corresponding injection / discharge port of the integrated four-channel electrolytic cell via a working fluid pipeline, enabling bidirectional transport of four working fluids between the electrolytic cell and the working fluid storage tank. The first delivery system consists of a working fluid pipeline sequentially equipped with a #1 working fluid storage tank, a #1 peristaltic pump, and a #1 solenoid valve. One end of the working fluid pipeline is connected to the #1... The first infusion system consists of a working fluid pipeline with a #2 working fluid storage tank, a #2 peristaltic pump, and a #2 solenoid valve connected in sequence, with one end of the working fluid pipeline connected to the #2 infusion port. The second infusion system consists of a working fluid pipeline with a #3 working fluid storage tank, a #3 peristaltic pump, and a #3 solenoid valve connected in sequence, with one end of the working fluid pipeline connected to the #3 infusion port. The third infusion system consists of a working fluid pipeline with a #3 working fluid storage tank, a #3 peristaltic pump, and a #3 solenoid valve connected in sequence, with one end of the working fluid pipeline connected to the #4 infusion port.

[0013] The aforementioned universal covalent functionalized graphene electrolytic preparation device comprises a shell and an integrated mounting mechanism. The shell consists of a front panel, a back panel, a top panel, a bottom panel, a left-side electrical components and control area side panel, and a right-side working liquid transport mechanism installation area transparent side panel, forming a compartment structure. The electrolytic cell body is fixed to the upper part of the front panel by a bracket. A transparent protective cover for the reaction zone is placed around the electrolytic cell body on the front panel, forming the reaction zone. The upper part of the front panel is equipped with wiring terminals, and the lower part of the front panel has heat dissipation holes. The interior of the electrolytic preparation device adopts a two-compartment layout. The right side is the working liquid transport mechanism installation area, and the left side is the electrical components and control area. The two areas are separated by a mounting motherboard, which serves as the system motherboard for installing various electrical and piping devices. The PLC-HMI controller, which serves as the core of the device's operation control and the human-machine interface, is embedded in the inner surface of the left-side electrical components and control area side panel.

[0014] The aforementioned general-purpose covalent functionalized graphene electrolytic preparation device has transparent plastic material on the left side of the device housing, which houses electrical components and control area, and on the right side, which houses the working liquid transport mechanism installation area. The back panel of the device housing integrates a power interface, a data communication interface, and a cooling fan. A handle is provided on the top surface of the device housing.

[0015] A method for using a universal covalent functionalized graphene electrolytic preparation device, wherein the preparation of CFG using this device requires two sequential operations: electrolytic intercalation and electrolytic oxidation.

[0016] Process one, electrolytic intercalation, consists of the following five steps:

[0017] Step 1: Add light sealing oil for working liquid #1, concentrated sulfuric acid intercalating agent for working liquid #2, aqueous electrolyte for working liquid #3, and heavy sealing oil for working liquid #4 to working liquid storage tanks #1, #2, #3, and #4 respectively, and connect the power supply.

[0018] Step 2: With the main body of the electrolytic cell empty, open solenoid valve 28 (#4) to draw high-density heavy sealing oil (#4 working liquid) from the storage tank (#4 working liquid) using peristaltic pump (#4) and push it into the main body of the electrolytic cell through the injection port (#4) at the bottom. The amount added should be controlled so that the sealing oil just covers the injection port (#3) and kept stable. Then close solenoid valve 28 (#4) and peristaltic pump (#4).

[0019] Step 3: Open solenoid valve #2 and use peristaltic pump #2 to extract concentrated sulfuric acid intercalating agent (working liquid #2) and inject it into the electrolytic cell body through injection port #2. When the liquid level reaches the lower level gauge position, open solenoid valve #1 and use peristaltic pump #1 to draw light sealing oil (working liquid #1) from the working liquid storage tank and push it into the electrolytic cell body through injection port #1 at the top of the electrolytic cell body. The initial amount added is set to form a sealing oil film with a height of 5mm. Then close solenoid valve #1 and peristaltic pump #1.

[0020] Step 4: When the level of the No. 2 working liquid concentrated sulfuric acid intercalating agent reaches the position of the upper level gauge, close the No. 2 solenoid valve and the No. 2 peristaltic pump; at this point, the pretreatment process of electrolytic intercalation is completed, and the electrolytic power supply is turned on to carry out static electrolytic intercalation.

[0021] Step 5: Open solenoid valves #1 and #2, and connect peristaltic pump #1 in the forward direction and peristaltic pump #2 in the reverse direction, so that they inject light sealing oil (working liquid #1) at the same speed while discharging the concentrated sulfuric acid intercalating agent (working liquid #2), ensuring that the liquid level of the sealing oil remains basically unchanged; when the interface between the light sealing oil (working liquid #1) and the concentrated sulfuric acid intercalating agent (working liquid #2) drops to the bottom of the injection / discharge port of #2, stop peristaltic pumps #1 and #2 and close solenoid valve #2. At this time, the discharge of the concentrated sulfuric acid intercalating agent (working liquid #2) is complete.

[0022] Process 2, electrolytic oxidation, consists of the following 3 steps:

[0023] Step 1: Open the No. 3 solenoid valve, use the No. 3 peristaltic pump to extract the No. 2 working liquid concentrated sulfuric acid intercalating agent and inject it into the main body of the electrolytic cell through the No. 3 injection port. When the injected liquid forms a liquid film with a thickness of 1 mm, stop the injection and close the No. 3 solenoid valve and the No. 3 peristaltic pump.

[0024] Step 2: Open solenoid valves #4 and #1. Peristaltic pump #4 rotates forward while peristaltic pump #1 rotates in reverse, injecting high-density working fluid (heavy sealing oil) from the #4 inlet / outlet port at the bottom of the electrolytic cell into the main body of the electrolytic cell. This pushes the aqueous electrolyte film of working fluid #3 to gradually rise. The light sealing oil of working fluid #1, discharged due to the rising liquid level, is then pumped back into the working fluid storage tank by peristaltic pump #1. When the aqueous electrolyte film of working fluid #3 rises to the lower level gauge position, adjust... Adjust the power supply voltage to the voltage required for electrolytic oxidation and gradually approach the GIC electrode to begin oxidation. When the level of the aqueous electrolyte in working liquid #3 rises to the position of the upper level gauge, the oxidation of this GIC electrode is completed, yielding CFG. At this point, stop the power supply, close solenoid valves #1 and #4, and the peristaltic pump. The electrolytic oxidation reaction process ends. At this time, all the light sealing oil in working liquid #1 will be completely discharged from the main body of the electrolytic cell, while the reaction product CFG will be immersed in the heavy sealing oil in working liquid #4.

[0025] Step 3: Open solenoid valve #4, and peristaltic pump #4 will reverse to discharge all the working liquid in the electrolytic cell into working liquid storage tank #4.

[0026] The method of using the general-purpose covalent functionalized graphene electrolytic preparation device is as follows: In step 4 of process one, after the electrolytic intercalation is completed, the No. 2 working liquid concentrated sulfuric acid intercalating agent is released from the main body of the electrolytic cell, and the No. 1 working liquid light sealing oil is injected simultaneously to ensure that the graphite interlayer compound obtained by intercalation is never in contact with air; In step 3 of process one, after the electrochemical reaction is completed, the product CFG sample strip is taken out from the main body of the electrolytic cell, the unreacted graphite paper is cut off, and it is placed in water for ultrasonic or shear peeling to obtain an aqueous dispersion of CFG.

[0027] The advantages and beneficial effects of this invention are as follows:

[0028] 1. This device can be used to efficiently prepare different types of CFG with high product purity and few by-products.

[0029] 2. The device can be used to prepare CFG, enabling automated control of the reaction process. Operators only need to add the appropriate working liquid to the corresponding working liquid storage tank and start the device. The device can then automatically carry out subsequent operations. The reaction process is free from disordered human intervention, is simple and easy to use, and the properties of different batches of products are highly consistent.

[0030] 3. The reaction device prepared by this invention is small and easy to use, and the preparation time is short. It is very suitable for the preparation of small quantities of CFG samples in the laboratory, and at the same time, it facilitates the research on related material preparation technologies. Attached Figure Description

[0031] Figures 1-4 A structural model diagram of the four-channel electrolytic reaction cell in the CFG electrolysis preparation apparatus. Figure 1 Main view, Figure 2 This is a side view. Figure 3 It is a 3D image. Figure 4 This is the cover for the electrolytic cell.

[0032] Figure 5 Model diagram of the conductive fixture mechanism for the anode graphite paper in the CFG electrolysis preparation apparatus. (a) is the front view, and (b) is a perspective view.

[0033] Figure 6 Model diagram of the working liquid transport mechanism of the CFG electrolysis preparation device.

[0034] Figures 7-10 .Overall structural model diagram of the CFG electrolysis preparation device. Among them, Figure 7 This is the back of the device (interface area). Figure 8 For the side of the device (electrical components and control area), Figure 9 This is the front of the device (reaction zone). Figure 10 This is the side of the device (the installation area for the working fluid transport mechanism).

[0035] Appendix Figure 1-10The components or devices referred to by the numbers are as follows: 1-Electrolytic cell body, 2-1# injection / exhaust port, 3-2# ​​injection / exhaust port, 4-3# injection / exhaust port, 5-4# injection / exhaust port, 6-Upper level gauge, 7-Lower level gauge, 8-Electrolytic cell cover, 9-Cathode rod, 10-Insulating partition, 11-Vent hole in cell cover, 12-Anode mounting hole, 13-Conductive clamp, 14-Clamping screw, 15-Anode graphite paper, 16-Terminal block, 17-1# working liquid storage tank, 18-1# peristaltic pump, 19-1# solenoid valve, 20-2# working liquid storage tank, 21-2# peristaltic pump, 22-2# solenoid valve, 23-3# working liquid storage tank, 24-3# peristaltic pump... 25-3# Solenoid valve, 26-4# Working liquid storage tank, 27-4# Peristaltic pump, 28-4# Solenoid valve, 29- Working liquid pipeline, 30- Base plate, 31- Working liquid transport mechanism installation area, 32- Electrical components and control area, 33- Reaction area, 34- Back panel, 35- Mounting main board, 36- Top plate, 37- Transparent side panel of working liquid transport mechanism installation area, 38- Front panel, 39- Transparent protective cover of reaction area, 40- Terminal block, 41- Heat dissipation holes, 42- Side panel of electrical components and control area, 43- PLC-HMI controller, 44- Cooling fan, 45- Data communication interface, 46- Power interface, 47- Handle. Detailed Implementation

[0036] In its specific implementation, this invention proposes a universal covalent functionalized graphene electrolytic preparation device, whose core components include five parts: a four-channel electrolytic reaction cell mechanism, an anode graphite paper conductive clamp mechanism, a working liquid transport mechanism, an electrical control mechanism, and a housing and installation integration mechanism. The specific structure is as follows:

[0037] like Figures 1-4 As shown, the four-channel electrolytic reactor structure comprises two parts: an integrated four-channel electrolytic reactor body 1 and a multifunctional electrolytic reactor cover 8, wherein:

[0038] The main body 1 of the integrated four-channel electrolytic cell is cylindrical with an open top for installing the electrolytic cell cover 8. There are four liquid passage openings on the side wall and bottom: 1# liquid inlet / outlet 2, 2# liquid inlet / outlet 3, 3# liquid inlet / outlet 4, and 4# liquid inlet / outlet 5, which are used for injecting and discharging the four working liquids (1#, 2#, 3#, and 4#) into the electrolytic cell, respectively. A hole is made on the side wall near the upper edge of the electrolytic cell body 1, and a single-hole inlet / outlet pipe is connected to it. The outer end of the single-hole inlet / outlet pipe is a No. 1 inlet / outlet port 2, which is used for the injection and discharge of the No. 1 working liquid. The bottom of the electrolytic cell body 1 adopts a hemispherical end cap. A hole is made at the bottom of the electrolytic cell body 1 and a pipe joint is connected to it. The pipe joint includes a vertical inlet / outlet pipe and two horizontal inlet / outlet pipes. The horizontal inlet / outlet pipes are arranged parallel to each other and are perpendicular to the vertical inlet / outlet pipes. The outer ports of the upper and lower horizontal inlet / outlet pipes are No. 2 inlet / outlet port 3 and No. 3 inlet / outlet port 4, respectively. The lower port of the vertical inlet / outlet pipe is No. 4 inlet / outlet port 5. The top hole of the pipe joint is connected to the electrolytic cell body 1. The No. 2 inlet / outlet port 3, No. 3 inlet / outlet port 4, and No. 4 inlet / outlet port 5 on the pipe joint are used for the injection and discharge of the No. 2 (top of the bottom), No. 3 (middle of the bottom), and No. 4 (bottom bottom) working liquids, respectively. Two sets of liquid level sensing components are installed on the side wall of the electrolytic cell body 1, mainly used to sense the start (lower liquid level gauge 7) and end (upper liquid level gauge 6) positions of the micro-liquid film operation. Resistive liquid level sensors or capacitive liquid level sensors can be used. The electrolytic cell body 1 can be made of glass, quartz, ceramic, metal or plastic. The basic requirement is that the material used can maintain physical or chemical stability for a long time after contact with the four types of working liquids.

[0039] The multifunctional electrolytic cell cover 8 is mainly used to install the cathode rod 9 and the insulating partition 10, and to support the anode graphite paper conductive clamp mechanism. The top of the electrolytic cell cover 8 has two cathode rod mounting holes, two partition mounting holes, two or more cell cover vent holes 11, and one anode mounting hole 12 that matches the shape of the anode graphite paper conductive clamp mechanism. The cathode rod 9 is made of inert conductive material, including but not limited to stainless steel, platinum, rhodium, gold, and other metallic materials or graphite and other non-metallic materials; the length of the cathode rod must ensure that it can contact the bottom of the inner cavity of the electrolytic cell body 1, and a certain wiring length must be reserved above the electrolytic cell cover 8 for connection with the power supply electrode. The insulating partition 10 is used to prevent accidental contact between the anode graphite paper 15 immersed in the electrolytic cell body 1 and the cathode rod 9 during the electrochemical reaction, which could cause a short circuit. The cell cover vent hole 11 is used to discharge gaseous byproducts that may be generated on the electrode surface during the electrochemical reaction, such as hydrogen and oxygen.

[0040] like Figure 5As shown, the conductive clamping mechanism for anode graphite paper includes two conductive clamping plates 13 with threaded holes. In use, the anode graphite paper 15 is clamped between the two conductive clamping plates 13, and secured by clamping screws 14 passing through the threaded holes, ensuring a tight grip of the anode graphite paper 15 by the conductive clamping plates 13, thus allowing current to be effectively conducted to the anode graphite paper 15. Terminals 16 are provided on the upper part of the two conductive clamping plates 13 for connection to the positive terminal of the power supply via wires. The upper part of the anode graphite paper 15, where it connects to the conductive clamping plates 13, corresponds to the oil seal area of ​​the electrolytic cell, while the remaining anode graphite paper 15 corresponds to the reaction area of ​​the electrolytic cell.

[0041] like Figure 6 As shown, the working fluid transport mechanism includes four sets of transport systems consisting of working fluid storage tanks, peristaltic pumps, bidirectional solenoid valves, and working fluid pipelines. Each set of transport systems is connected to the corresponding injection and discharge ports of the integrated four-channel electrolytic cell body 1 through the working fluid pipeline, and is used for bidirectional transport of four types of working fluids between the electrolytic cell and the working fluid storage tank. The first infusion system consists of a working fluid pipeline 29, on which a No. 1 working fluid storage tank 17, a No. 1 peristaltic pump 18, and a No. 1 solenoid valve 19 are sequentially installed. One end of the working fluid pipeline 29 is connected to the No. 1 injection / drainage port 2. The second infusion system consists of a working fluid pipeline, on which a No. 2 working fluid storage tank 20, a No. 2 peristaltic pump 21, and a No. 2 solenoid valve 22 are sequentially installed. One end of the working fluid pipeline is connected to the No. 2 injection / drainage port 3. The third infusion system consists of a working fluid pipeline, on which a No. 3 working fluid storage tank 23, a No. 3 peristaltic pump 24, and a No. 3 solenoid valve 25 are sequentially installed. One end of the working fluid pipeline is connected to the No. 3 injection / drainage port 4. The fourth infusion system consists of a working fluid pipeline, on which a No. 4 working fluid storage tank 26, a No. 4 peristaltic pump 27, and a No. 4 solenoid valve 28 are sequentially installed. One end of the working fluid pipeline is connected to the No. 4 injection / drainage port 5. Working liquid storage tank 17, working liquid storage tank 20, working liquid storage tank 23, and working liquid storage tank 26 are all installed on the base plate 30.

[0042] The electrical control mechanism mainly includes: power supply for electrical components of the device (220V AC to 12V / 24V DC power supply), electrolysis power supply (high-precision DC numerical control constant voltage / constant current power supply), peristaltic pump stepper motor and controller, solenoid valve control relay, liquid level sensor, programmable logic controller (PLC), touch screen human-machine interface (HMI) and circuit connection system between various electrical components.

[0043] The housing and mounting integration mechanism mainly includes the device housing, the mounting space for various components inside the housing, and the controller, circuit / gas / liquid interface, and protective devices for key components mounted on the housing surface. This mechanism integrates the aforementioned four-channel electrolytic reaction cell mechanism, anode graphite paper conductive fixture mechanism, working fluid transport mechanism, and electrical control mechanism into a single independent device, enabling efficient CFG preparation.

[0044] The present invention will be further described in detail below through embodiments.

[0045] Example 1

[0046] like Figures 1-4 As shown, the multi-channel electrolytic cell is designed using quartz glass. The electrolytic cell body 1 has four injection / drainage ports (injection / drainage port 1#, 2#, 3#, 4#, and 5#) on its bottom and walls, and two sets of level sensing probes (upper level gauge 6 and lower level gauge 7). Their basic functions are as follows:

[0047] 1# Inlet / outlet port 2: Used for the inlet and outlet of the upper sealing oil (working fluid 1).

[0048] 2# Inlet / Outlet 3: Used for the inlet and outlet of the intercalating agent (working liquid 2).

[0049] 3# Inlet / Outlet 4: Used for the inlet and outlet of aqueous reactive electrolyte (working liquid 3).

[0050] 4# Inlet / Outlet 5: Used for the inlet and outlet of the lower sealing oil (working liquid 4), and for draining the working liquid from the main body 1 of the electrolytic cell after the reaction is completed.

[0051] Upper liquid level probe: used to determine the highest position of the intercalating agent and the reaction electrolyte level rise. It is used for automatic control by collecting the solution conductivity change signal. Its specific position is preset to be about 2mm below the bottom of the No. 1 injection / drain port 2.

[0052] The lower liquid level probe is used to determine the initial liquid level of the oxidation reaction. It collects the change signal of solution conductivity for automatic control. Its specific position is preset to be about 2 mm below the bottom edge of the fixed anode graphite paper 15.

[0053] The electrolytic cell cover 8 is used to fix the moving parts of the electrolytic reaction, including: a cathode rod 9, an insulating partition 10, and an anode graphite paper conductive clamp mechanism. The cathode rod 9 is made of stainless steel, and the insulating partition 10 is made of quartz glass; the insulating partition 10 and the electrolytic cell cover 8 are vertically positioned by a tight fit. The electrolytic cell cover 8 has four vent holes 11 for discharging gaseous byproducts from the electrolytic reaction; the vent holes 11 can also be used as temporary filling holes for liquid materials. A square anode mounting hole 12 is opened in the center of the electrolytic cell cover 8 for inserting the anode graphite paper conductive clamp mechanism and the anode graphite paper 15.

[0054] like Figure 5As shown, the conductive clamping mechanism for the anode graphite paper consists of two conductive clamping plates 13 (thick copper plates). The two conductive clamping plates 13 secure the anode graphite paper 15 (narrow strips of graphite paper) in the middle with clamping screws 14 to ensure good electrical contact and clamping force, while also ensuring ease of operation. After the clamped anode graphite paper 15 is inserted into the electrolytic cell body 1 through the anode mounting hole 12 in the middle of the electrolytic cell cover 8, the conductive clamping plates 13 act as supports, fixing them to the surface of the electrolytic cell cover 8 and forming a positioning system, which ensures the consistency of the relative position of the electrodes in each reaction.

[0055] like Figure 6 As shown, the working liquid transport mechanism of the integrated electrolysis preparation device utilizes a pathway consisting of a working liquid storage tank, a working liquid pipeline, a peristaltic pump, a solenoid valve, and the electrolysis cell body 1. Four different working liquids are stored in four separate tanks. The flow direction of the working liquid is controlled by the forward and reverse rotation of the peristaltic pump. The solenoid valve controls the opening and closing of its respective liquid pathway; the peristaltic pump can only control the flow of the working liquid when the solenoid valve is open. The working liquid pipeline connects the various components, forming the liquid transport channel. Both the peristaltic pump and the solenoid valve can be automatically controlled by a PLC.

[0056] like Figures 1-10 As shown, using the universal covalent functionalized graphene electrolytic preparation device of this invention, the preparation of CFG requires two sequential operations: electrolytic intercalation and electrolytic oxidation. Each process is divided into multiple steps, and its basic process flow and control process are as follows:

[0057] Process one, electrolytic intercalation, consists of the following five steps:

[0058] Step 1: Add working liquid #1 (light sealing oil), working liquid #2 (concentrated sulfuric acid intercalating agent), working liquid #3 (containing water electrolyte), and working liquid #4 (heavy sealing oil) to working liquid storage tanks #1 (17), #2 (20), #3 (23), and #4 (26) respectively, and then connect the power supply.

[0059] Step 2: With the main body 1 of the electrolytic cell empty, open the No. 4 solenoid valve 28 to draw the high-density lower layer sealing oil from the No. 4 working liquid storage tank 26 by the No. 4 peristaltic pump 27, and push it into the main body 1 of the electrolytic cell through the No. 4 injection port 5 at the bottom of the main body 1. The amount added should be controlled so that the sealing oil just covers the No. 3 injection port 4 and remains stable. Then close the No. 4 solenoid valve 28 and the No. 4 peristaltic pump 27.

[0060] Step 3: Open solenoid valve 22 (#2) and use peristaltic pump 21 (#2) to extract the intercalating agent and inject it into the electrolytic cell body 1 through injection port 3 (#2). When the liquid level reaches the lower level gauge 7, open solenoid valve 19 (#1). The upper sealing oil is then drawn from working liquid storage tank 17 by peristaltic pump 18 (#1) and pushed into the electrolytic cell body 1 through injection port 2 (#1) at the top. The initial injection amount is set to form a sealing oil film approximately 5 mm high. Then close solenoid valve 19 (#1) and peristaltic pump 18 (#1). The injection rate of the intercalating agent remains constant throughout this process.

[0061] Step 4: When the level of the intercalating agent reaches the position of the upper level gauge 6, close the No. 2 solenoid valve 22 and the No. 2 peristaltic pump 21; at this point, the pretreatment process of electrolytic intercalation is completed, and the electrolytic power supply can be turned on for static electrolytic intercalation.

[0062] After electrolytic intercalation is completed, the intercalating agent needs to be released from the main body of the electrolytic cell 1, and the upper sealing oil needs to be injected simultaneously to ensure that the graphite intercalation compound (GIC) obtained by intercalation never comes into contact with air. To achieve this, the following controls are required:

[0063] Step 5: Open solenoid valves 1# (19) and 2# (22), and connect peristaltic pump 1# (18) in the forward direction and peristaltic pump 2# (21) in the reverse direction, so that they inject upper sealing oil at the same speed while discharging the intercalating agent, ensuring that the liquid level of the sealing oil remains basically constant. When the interface between the upper sealing oil and the intercalating agent drops to the bottom of the 2# injection / discharge port 3, stop peristaltic pumps 1# (18) and 2# (21) and close solenoid valve 2# (22). At this point, the intercalating agent discharge is complete. The first step of the intercalation process is now complete.

[0064] Process 2, electrolytic oxidation, consists of the following 3 steps:

[0065] Step 1: Open solenoid valve 25 (#3) and use peristaltic pump 24 (#3) to extract the intercalating agent and inject it into the main body 1 of the electrolytic cell through injection port 4 (#3). When the injected amount can form a liquid film with a thickness of about 1 mm (the thickness of the liquid film is a key variable and the optimal value will be sought through experimental research), stop the injection and close solenoid valve 25 (#3) and peristaltic pump 24 (#3).

[0066] Step 2: Open solenoid valve 28 (#4) and solenoid valve 19 (#1). Peristaltic pump 27 (#4) rotates forward while peristaltic pump 18 (#1) rotates in reverse. High-density lower-layer sealing oil is injected into the electrolytic cell body 1 through inlet / outlet port 5 (#4) at the bottom, gradually raising the electrolyte film. The upper-layer sealing oil discharged due to the rising liquid level is pumped back into working liquid tank 17 (#1) by peristaltic pump 18. The electrolyte film can initially rise rapidly. When the electrolyte film reaches the lower level gauge 7, adjust the power supply voltage to the required voltage for electrolytic oxidation and begin operation at a controlled speed (both the voltage and film rise speed are key variables, and the optimal values ​​will be sought through experimental research). Gradually approach the GIC electrode to begin oxidation. When the electrolyte level rises to position 6 on the upper level gauge, the oxidation of this GIC electrode is complete, yielding CFG. At this point, the power is stopped, and solenoid valves 1# and 28# and the peristaltic pump are closed, ending the electrolytic oxidation reaction. All the upper sealing oil will then be completely drained from the electrolytic cell body 1, while the reaction product CFG will remain immersed in the lower sealing oil. Based on previous experimental observations and the oleophobic properties of CFG, the reacted CFG will still aggregate in the form of sample strips, rather than being directly stripped into the liquid phase.

[0067] Step 3: Open solenoid valve 28 (#4), and peristaltic pump 27 (#4) reverses direction to discharge all working liquid from the main body of the electrolytic cell 1 into working liquid storage tank 26 (#4). This completes the second step of the electrolytic oxidation process.

[0068] After the electrochemical reaction is completed, the CFG sample strip is removed from the main body 1 of the electrolytic cell, the unreacted graphite paper is cut off, and then it is placed in water for ultrasonic or shear peeling to obtain an aqueous dispersion of CFG.

[0069] like Figures 7-10As shown, this invention presents a general-purpose covalent functionalized graphene electrolytic preparation device, which consists of a housing and an integrated mounting mechanism. The overall dimensions of the device are estimated to be 230mm (width) × 400mm (height) × 480mm (length, including the electrolytic cell body 1). The housing is formed by a front panel 38, a back panel 34, a top plate 36, a bottom plate 30, a left-side side panel 42 for electrical components and control area, and a right-side transparent side panel 37 for the working liquid transport mechanism mounting area. The electrolytic cell body 1 is fixed to the upper part of the front panel 38 by a bracket. To facilitate experimental observation and protect the quartz glass electrolytic cell body 1 from impact damage, a transparent protective cover 39 for the reaction zone is placed around the electrolytic cell body 1 on the front panel 38, forming a reaction zone 33. The upper part of the front panel 38 is provided with terminals 40, and the lower part of the front panel 38 is provided with heat dissipation holes 41. The internal structure of the electrolysis preparation device adopts a two-compartment layout. The right side is the installation area 31 for the working liquid transport mechanism, and the left side is the electrical components and control area 32. The two areas on the left and right sides are separated by a mounting motherboard 35, which also serves as the system motherboard for installing various electrical and piping devices.

[0070] All electrical components are mounted at a height far from the base plate 30 to prevent damage from accidental leakage of working fluid. To facilitate real-time observation of the working fluid transport and electrical component operation within the electrolysis preparation device, both the left and right side panels of the device's casing (left side panel 42 for electrical components and control area, and right side panel 37 for the working fluid transport mechanism installation area) are made of transparent plastic. The PLC-HMI controller 43, serving as the core of the device's control and the human-machine interface, is embedded on the inner surface of the left side panel 42 for easy control operation. The back panel 34 of the electrolysis preparation device's casing integrates a power interface 46, a data communication interface 45, and a cooling fan 44. The entire unit weighs approximately 15 kg, and a handle 47 is provided on the top plate 36 of the casing for easy single-person handling.

[0071] The results demonstrate that this invention, through integrated design, combines the automated control system and the working fluid system into a small, independently operable preparation device, enabling efficient and controlled preparation of small-batch experimental functionalized graphene. This invention represents a key advancement in the transformation of the electrochemical preparation of covalently functionalized graphene from a method to an applied technology, and has significant application value.

Claims

1. A universal covalent functionalized graphene electrolytic preparation device, characterized in that, The device includes: a four-channel electrolytic reaction cell mechanism, a graphite paper electrode conductive clamp mechanism, a working fluid transport mechanism, an electrical control mechanism, and a housing and installation integration mechanism. The specific structure is as follows: The graphite paper electrode conductive clamp mechanism is installed in the electrode mounting hole on the electrolytic cell cover of the four-channel electrolytic reaction cell mechanism. The graphite paper electrode conductive clamp mechanism clamps the upper end of the graphite paper electrode, which extends into the inner cavity of the electrolytic cell body. The four sets of liquid delivery systems of the working liquid delivery mechanism are connected to the four injection and discharge ports of the four-channel electrolytic reaction cell mechanism through the working liquid pipeline. The four-channel electrolytic reaction cell mechanism, the anode graphite paper conductive clamp mechanism, the working liquid delivery mechanism, and the electrical control mechanism are integrated and installed in the housing and the installation integration mechanism. The four-channel electrolytic reactor structure comprises two parts: an integrated four-channel electrolytic reactor body and a multi-functional electrolytic reactor cover. The integrated four-channel electrolytic reactor body is cylindrical, with an open top for installing the electrolytic reactor cover. It has four liquid passage openings on the side walls and bottom: 1# injection / drainage port, 2# injection / drainage port, 3# injection / drainage port, and 4# injection / drainage port. A hole is made on the side wall near the upper edge of the electrolytic reactor body, connecting to a single-hole inlet / drainage pipe. The outer end of the single-hole inlet / drainage pipe is the 1# injection / drainage port. The bottom of the electrolytic reactor body uses a hemispherical end cap. An opening is located at the very bottom of the electrolytic reactor body and connected to a pipe connector, which includes a vertical inlet / drainage port. The electrolytic cell has a liquid inlet pipe and two horizontal inlet / outlet pipes. The horizontal inlet / outlet pipes are arranged parallel to each other and are vertically connected to the vertical inlet / outlet pipe. The outer ports of the upper and lower horizontal inlet / outlet pipes are respectively the No. 2 and No. 3 inlet / outlet ports. The lower port of the vertical inlet / outlet pipe is the No. 4 inlet / outlet port. The uppermost opening of the pipe joint is connected to the main body of the electrolytic cell. The multifunctional electrolytic cell cover is equipped with cathode rods and insulating partitions, and supports the anode graphite paper conductive clamp mechanism. The top of the electrolytic cell cover is provided with two cathode rod mounting holes, two partition mounting holes, two or more cell cover vent holes, and one anode mounting hole that matches the shape of the anode graphite paper conductive clamp mechanism. A lower level gauge and an upper level gauge are installed on the side wall of the electrolytic cell body to sense the starting position and ending position of the micro-liquid film. The lower level gauge and the upper level gauge are resistive level sensors or capacitive level sensors. The electrolytic cell body is made of glass, quartz, ceramic, metal or plastic. The working fluid transport mechanism comprises four sets of transport systems consisting of working fluid storage tanks, peristaltic pumps, bidirectional solenoid valves, and working fluid pipelines. Each transport system is connected to the corresponding injection / discharge port of the integrated four-channel electrolyzer via a working fluid pipeline, enabling bidirectional transport of four types of working fluids between the electrolyzer and the working fluid storage tanks. The first transport system consists of a working fluid pipeline with a No. 1 working fluid storage tank, a No. 1 peristaltic pump, and a No. 1 solenoid valve sequentially installed, with one end of the pipeline connected to the No. 1 injection / discharge port. The second transport system... The first fluid system consists of a working fluid pipeline with a #2 working fluid storage tank, a #2 peristaltic pump, and a #2 solenoid valve arranged sequentially. One end of the working fluid pipeline is connected to the #2 injection / drain port. The second fluid system consists of a working fluid pipeline with a #3 working fluid storage tank, a #3 peristaltic pump, and a #3 solenoid valve arranged sequentially. One end of the working fluid pipeline is connected to the #3 injection / drain port. The third fluid system consists of a working fluid pipeline with a #4 working fluid storage tank, a #4 peristaltic pump, and a #4 solenoid valve arranged sequentially. One end of the working fluid pipeline is connected to the #4 injection / drain port.

2. The universal covalent functionalized graphene electrolytic preparation device according to claim 1, characterized in that, The cathode rod is made of inert conductive material. The length of the cathode rod ensures that it can contact the bottom of the inner cavity of the electrolytic cell body, and a certain wiring length is reserved above the electrolytic cell cover for connection with the power supply electrode.

3. The universal covalent functionalized graphene electrolytic preparation apparatus according to claim 1, characterized in that, The conductive clamping mechanism for anode graphite paper includes two conductive clamping plates with threaded holes. The anode graphite paper is clamped between the two conductive clamping plates and secured by clamping screws through the threaded holes, ensuring that the conductive clamping plates tightly hold the anode graphite paper. Terminals are provided on the upper part of the two conductive clamping plates for connection to the positive terminal of the power supply via wires. The upper part of the anode graphite paper, where it connects to the conductive clamping plates, corresponds to the oil seal area of ​​the electrolytic cell, while the remaining anode graphite paper corresponds to the reaction area of ​​the electrolytic cell.

4. The universal covalent functionalized graphene electrolytic preparation apparatus according to claim 1, characterized in that, The device as a whole adopts a shell and installation integrated mechanism. The shell is composed of a front panel, a back panel, a top panel, a bottom panel, a left side panel for electrical components and control area, and a right side panel for the working liquid transport mechanism installation area, forming a compartment structure. The main body of the electrolytic cell is fixed to the upper part of the front panel by a bracket. The transparent protective cover of the reaction zone is placed around the main body of the electrolytic cell on the front panel to form the reaction zone. The upper part of the front panel is equipped with wiring terminals, and the lower part of the front panel has heat dissipation holes. The interior of the shell of the electrolytic preparation device adopts a two-compartment layout. The right side is the installation area for the working liquid transport mechanism, and the left side is the electrical components and control area. The two areas on the left and right sides are separated by a mounting motherboard, which serves as the system motherboard for installing various electrical and piping devices. The PLC-HMI controller, which serves as the core of the device's working control and the human-machine interface, is embedded in the inner surface of the left side panel for electrical components and control area.

5. The universal covalent functionalized graphene electrolytic preparation apparatus according to claim 1, characterized in that, The electrical components and control area side panel on the left side of the electrolysis preparation device housing, and the transparent side panel of the working liquid transport mechanism installation area on the right side are all made of transparent plastic. The power interface, data communication interface, and cooling fan are integrated on the back panel of the electrolysis preparation device housing, and a handle is provided on the top surface of the top panel of the electrolysis preparation device housing.

6. A method of using the universal covalent functionalized graphene electrolytic preparation apparatus according to any one of claims 1 to 5, characterized in that, The preparation of CFG using this device requires two sequential processes: electrolytic intercalation and electrolytic oxidation. Process one, electrolytic intercalation, consists of the following five steps: Step 1: Add light sealing oil for working liquid #1, concentrated sulfuric acid intercalating agent for working liquid #2, aqueous electrolyte for working liquid #3, and heavy sealing oil for working liquid #4 to working liquid storage tanks #1, #2, #3, and #4 respectively, and connect the power supply. Step 2: With the main body of the electrolytic cell empty, open the No. 4 solenoid valve to draw the high-density No. 4 working liquid heavy sealing oil from the No. 4 working liquid storage tank by the No. 4 peristaltic pump, and push it into the main body of the electrolytic cell from the No. 4 injection port at the bottom of the main body of the electrolytic cell. The amount added should be controlled so that the heavy sealing oil just covers the No. 3 injection port and remain stable. Then close the No. 4 solenoid valve and the No. 4 peristaltic pump. Step 3: Open solenoid valve #2 and use peristaltic pump #2 to extract concentrated sulfuric acid intercalating agent (working liquid #2) and inject it into the electrolytic cell body through injection port #2. When the liquid level reaches the lower level gauge position, open solenoid valve #1 and use peristaltic pump #1 to draw light sealing oil (working liquid #1) from the working liquid storage tank and push it into the electrolytic cell body through injection port #1 at the top of the electrolytic cell body. The initial amount added is set to form a sealing oil film with a height of 5mm. Then close solenoid valve #1 and peristaltic pump #1. Step 4: When the level of the No. 2 working liquid concentrated sulfuric acid intercalating agent reaches the position of the upper level gauge, close the No. 2 solenoid valve and the No. 2 peristaltic pump; at this point, the pretreatment process of electrolytic intercalation is completed, and the electrolytic power supply is turned on to carry out static electrolytic intercalation. Step 5: Open solenoid valves #1 and #2, and connect peristaltic pump #1 in the forward direction and peristaltic pump #2 in the reverse direction, so that they inject light sealing oil (working liquid #1) at the same speed while discharging the concentrated sulfuric acid intercalating agent (working liquid #2), ensuring that the liquid level of the sealing oil remains basically unchanged; when the interface between the light sealing oil (working liquid #1) and the concentrated sulfuric acid intercalating agent (working liquid #2) drops to the bottom of the injection / discharge port of #2, stop peristaltic pumps #1 and #2 and close solenoid valve #2. At this time, the discharge of the concentrated sulfuric acid intercalating agent (working liquid #2) is complete. Process 2, electrolytic oxidation, consists of the following 3 steps: Step 1: Open the No. 3 solenoid valve, use the No. 3 peristaltic pump to extract the No. 2 working liquid concentrated sulfuric acid intercalating agent and inject it into the main body of the electrolytic cell through the No. 3 injection port. When the injected liquid forms a liquid film with a thickness of 1 mm, stop the injection and close the No. 3 solenoid valve and the No. 3 peristaltic pump. Step 2: Open solenoid valves #4 and #1. Peristaltic pump #4 rotates forward while peristaltic pump #1 rotates in reverse, injecting high-density working fluid (heavy sealing oil) from the #4 inlet / outlet port at the bottom of the electrolytic cell into the main body of the electrolytic cell. This pushes the aqueous electrolyte film of working fluid #3 to gradually rise. The light sealing oil of working fluid #1, discharged due to the rising liquid level, is then pumped back into the working fluid storage tank by peristaltic pump #1. When the aqueous electrolyte film of working fluid #3 rises to the lower level gauge position, adjust... Adjust the power supply voltage to the voltage required for electrolytic oxidation and gradually approach the GIC electrode to begin oxidation. When the level of the aqueous electrolyte in working liquid #3 rises to the position of the upper level gauge, the oxidation of this GIC electrode is completed, yielding CFG. At this point, stop the power supply, close solenoid valves #1 and #4, and the peristaltic pump. The electrolytic oxidation reaction process ends. At this time, all the light sealing oil in working liquid #1 will be completely discharged from the main body of the electrolytic cell, while the reaction product CFG will be immersed in the heavy sealing oil in working liquid #4. Step 3: Open solenoid valve #4, and peristaltic pump #4 will reverse to discharge all the working liquid in the electrolytic cell into working liquid storage tank #4; CFG refers to covalently functionalized graphene, and GIC refers to graphite intercalation compounds.

7. The method of using the universal covalent functionalized graphene electrolytic preparation device according to claim 6, characterized in that, In step 4 of process one, after the electrolytic intercalation is completed, the No. 2 working liquid concentrated sulfuric acid intercalating agent is released from the main body of the electrolytic cell, and the No. 1 working liquid light sealing oil is injected simultaneously to ensure that the graphite intercalation compound obtained by intercalation is never in contact with air. In step 3 of process one, after the electrochemical reaction is completed, the product CFG sample strip is taken out from the main body of the electrolytic cell, the unreacted graphite paper is cut off, and it is placed in water for ultrasonic or shear peeling to obtain an aqueous dispersion of CFG.

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