Electrochemical ito integrated flexible electrode
By integrating the working electrode, reference electrode, and counter electrode on a flexible substrate, the problems of fragility and complex operation of ITO glass electrodes are solved, achieving stability and portability of electrochemical detection, making it suitable for field applications.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- NANJING YUNYOU BIOTECHNOLOGY CO LTD
- Filing Date
- 2025-07-30
- Publication Date
- 2026-08-04
AI Technical Summary
ITO glass electrodes are fragile, complex to operate, and not portable. Traditional discrete electrodes increase the number of operating steps, affecting electrochemical reversibility and portable applications.
By employing a flexible substrate and membrane structure, the working electrode, reference electrode, and counter electrode are integrated together. Electrochemical ITO integrated flexible electrodes are fabricated through printing, stamping, and hot-pressing composite processes, reducing the risk of fragility and scratches and improving stability and reliability.
It improves the stability and reliability of electrochemical detection, simplifies the operation process, reduces production costs, and is suitable for field application scenarios.
Smart Images
Figure CN224594556U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the technical field of electrochemical analysis, and in particular to an electrochemical ITO integrated flexible electrode. Background Technology
[0002] Electrochemical analysis is an analytical method based on the electrochemical properties of substances in solution and at electrodes. Conventional electrochemical analysis employs a three-electrode system, including a working electrode, a reference electrode, and a counter electrode. However, using discrete three electrodes is inconvenient to operate and carry in practice, thus an integrated electrode has emerged. This integrated electrode integrates the working electrode, reference electrode, and counter electrode together through printing, and its size can be arbitrarily designed according to the intended use, greatly facilitating electrochemical analysis operations in practical work.
[0003] In a three-electrode system, the working electrode typically uses conductive materials such as glassy carbon, graphite, or gold; the reference electrode is usually a silver chloride electrode or a calomel electrode; and the counter electrode is typically a platinum electrode or a carbon electrode. The material of the working electrode affects the electrochemical performance. Indium tin oxide (ITO) is a semiconductor material with excellent conductivity, visible light transmittance, and chemical stability, and it can be deposited on a transparent substrate to form a conductive thin film. A layer of ITO conductive film deposited using magnetron sputtering exhibits high transmittance. Currently, ITO electrodes are widely used in the construction of sensors, especially photoelectrochemical and electrochemical sensors. ITO electrodes are mostly based on glass substrates, and ITO glass electrodes are used as working electrodes in various electrochemical analysis fields, especially as transparent electrodes, which are particularly suitable for photoelectrochemical analysis.
[0004] However, when used as a working electrode, ITO glass electrodes present risks such as fragility, complex operation, and the risk of injury from glass cuts. Furthermore, the use of separate reference and counter electrodes increases the number of steps involved and makes them less portable. This limits the widespread application of ITO glass electrodes in analytical applications.
[0005] In related technologies, CN101482534A integrates ITO electrodes into a three-electrode system to meet the application requirements of ease of operation, especially suitable for field applications. However, CN101482534A involves acid etching of the conductive layer on a pre-cut ITO conductive glass to form three electrodes. The counter and reference electrodes are not conventional electrode materials, making the fabrication relatively complex and prone to electrode breakage or scratches, resulting in poor electrochemical reversibility. Therefore, there is an urgent need to develop a novel three-electrode system to improve the electrochemical reversibility of the integrated ITO electrode three-electrode system. Utility Model Content
[0006] To improve the electrochemical reversibility of integrated three-electrode systems with ITO electrodes, this application provides an electrochemical ITO integrated flexible electrode, its preparation method, and its application.
[0007] Firstly, this application provides an electrochemical ITO integrated flexible electrode, which adopts the following technical solution:
[0008] An electrochemical ITO integrated flexible electrode includes a working electrode layer, a composite bonding layer, and an auxiliary electrode layer arranged sequentially from bottom to top. The working electrode layer includes a membrane substrate and an ITO conductive layer disposed on the membrane substrate. The auxiliary electrode layer includes a flexible substrate, a conductive layer, and an insulating layer arranged sequentially from bottom to top. The flexible substrate is bonded to the ITO conductive layer through the composite bonding layer. The flexible substrate has an electrolytic cell cavity region and a contact region, both of which are located outside the coverage area of the insulating layer. The flexible substrate has a hollowed-out circular region and a hollowed-out square region penetrating the auxiliary electrode layer. The hollowed-out circular region is located within the electrolytic cell cavity region, and the hollowed-out square region is located within the contact region. The area of the working electrode layer opposite to the hollowed-out circular region is the ITO working electrode, and the area of the working electrode layer opposite to the hollowed-out square region is the contact of the ITO working electrode.
[0009] In one specific implementation, the conductive layer includes a reference electrode, a counter electrode, an electrode rail, and a rail contact plate disposed on a flexible substrate. The reference electrode and the counter electrode are both connected to the electrode rail, and the rail contact plate is connected to the end of the electrode rail. The insulating layer covers the electrode rail, the reference electrode and the counter electrode are located within the electrolytic cell cavity, and the rail contact plate is located within the contact plate area.
[0010] In one specific implementation, the membrane substrate is made of any one of polyethylene terephthalate, polyimide, or polyethylene, the thickness of the membrane substrate is 50-200 μm, the flexible substrate is made of the same material and has the same dimensions as the membrane substrate, the ITO conductive layer has a thickness of 50-200 nm, and the sheet resistance of the ITO conductive layer is ≤10 Ω / □.
[0011] In one specific implementation, the composite adhesive layer is an ethylene-vinyl acetate copolymer hot melt adhesive layer or a polyamide hot melt adhesive layer, and the thickness of the composite adhesive layer is 20-100 μm.
[0012] In one specific implementation, the thickness of the conductive layer is 5-20 μm.
[0013] Secondly, this application provides a method for fabricating an electrochemical ITO integrated flexible electrode, which employs the following technical solution:
[0014] A method for fabricating an electrochemical ITO integrated flexible electrode includes the following steps:
[0015] The membrane substrate is cleaned and dried, and an ITO conductive layer is deposited on the membrane substrate. The thickness of the ITO conductive layer is controlled to be 50-200 nm to obtain an ITO flexible membrane.
[0016] Conductive ink is printed on a flexible substrate to form a reference electrode, a counter electrode, an electrode rail, and a rail contact. The reference electrode, counter electrode, electrode rail, and rail contact together form a conductive layer. After the conductive layer dries, insulating ink is printed on the conductive layer to form an insulating layer. An electrolytic cell cavity and a contact area are formed in the area outside the coverage of the insulating layer on the flexible substrate. The flexible substrate, the conductive layer, and the insulating layer together form an auxiliary electrode sheet.
[0017] A hollowed-out circular area is stamped out in the electrolytic cell cavity of the flexible substrate, and a hollowed-out square area is stamped out in the contact area of the flexible substrate.
[0018] Using an ITO flexible film as the working electrode layer, the working electrode layer is bonded to the flexible substrate of the auxiliary electrode layer with hot melt adhesive. After hot pressing, the hot melt adhesive forms a composite bonding layer. After cutting, an electrochemical ITO integrated flexible electrode is obtained.
[0019] In one specific implementation scheme, the hot-pressing composite temperature is 80-150℃, the pressure is 0.5-2MPa, and the time is 5-10 minutes.
[0020] In one specific feasible implementation, after hot pressing, the material is held at a temperature of 60-80℃ and a pressure of 0.5-1MPa for 1-3 minutes before cutting.
[0021] In one specific feasible implementation, an ITO conductive layer is deposited on a film substrate using magnetron sputtering or electron beam evaporation processes.
[0022] Thirdly, the application of the electrochemical ITO integrated flexible electrode provided in this application adopts the following technical solution:
[0023] An application of an electrochemical ITO integrated flexible electrode, wherein the electrochemical ITO integrated flexible electrode is used in electrochemical detection.
[0024] In summary, this application has the following beneficial effects:
[0025] 1. This application combines a working electrode sheet and an auxiliary electrode sheet together using a composite bonding layer to obtain an integrated electrochemical ITO electrode. The working electrode sheet provides the ITO working electrode, while the auxiliary electrode sheet provides the reference and counter electrodes, thus constructing a three-electrode system integrating the ITO working electrode, reference electrode, and counter electrode. The use of a flexible substrate and flexible film structure reduces the risk of fragility and scratches on the ITO electrode. Furthermore, integrating the working electrode, reference electrode, and counter electrode into the same flexible structure results in high integration, reduces the complexity of connections between electrodes, improves the stability and reliability of the detection system, and broadens the application range of the electrode.
[0026] 2. The preparation method of this application adopts processes such as printing, stamping and hot pressing, which is simple to operate, suitable for mass production, and reduces production costs.
[0027] 3. The electrochemical ITO integrated flexible electrode of this application can be used in electrochemical detection, meeting the application requirements of easy operation, especially suitable for field application scenarios. Attached Figure Description
[0028] Figure 1 This is a schematic diagram of the structure of the electrochemical ITO integrated electrode in Example 1 of this application.
[0029] Figure 2 This is a cross-sectional view of the electrochemical ITO integrated electrode in Example 1 of this application.
[0030] Figure 3 This is a schematic diagram of the fabrication process of the electrochemical ITO integrated electrode in Example 1 of this application.
[0031] Figure 4 This is an electrochemical potassium ferricyanide cyclic voltammetric scan of the electrochemical ITO integrated flexible electrode of Example 1 of this application.
[0032] Reference numerals: 1. Working electrode sheet; 2. Composite bonding sheet; 3. Auxiliary electrode sheet; 4. Conductive layer; 5. Insulating layer; 6. Membrane substrate; 7. ITO conductive layer; 8. ITO working electrode; 9. Reference electrode; 10. Counter electrode; 11. Electrode rail; 12. Rail contact; 13. Electrolytic cell cavity area; 14. Contact area; 15. Hollowed-out circular area; 16. Hollowed-out square area; 17. Flexible substrate. Detailed Implementation
[0033] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings.
[0034] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.
[0035] Secondly, the term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that excludes other embodiments.
[0036] Secondly, this utility model is described in detail with reference to the schematic diagrams. When describing the embodiments of this utility model, for ease of explanation, the cross-sectional views illustrating the device structure may be partially enlarged, not adhering to the usual scale. Furthermore, the schematic diagrams are merely examples and should not limit the scope of protection of this utility model. In addition, actual manufacturing should include the three-dimensional spatial dimensions of length, width, and depth.
[0037] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings.
[0038] Many specific details are set forth in the following description in order to provide a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Those skilled in the art can make similar extensions without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.
[0039] Secondly, the term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that excludes other embodiments.
[0040] Secondly, this utility model is described in detail with reference to the schematic diagrams. When describing the embodiments of this utility model, for ease of explanation, the cross-sectional views illustrating the device structure may be partially enlarged, not adhering to the usual scale. Furthermore, the schematic diagrams are merely examples and should not limit the scope of protection of this utility model. In addition, actual manufacturing should include the three-dimensional spatial dimensions of length, width, and depth.
[0041] The present application will be further described in detail below with reference to embodiments and comparative examples.
[0042] Example 1
[0043] like Figure 1-3 As shown, this embodiment provides an electrochemical ITO integrated flexible electrode, comprising a working electrode layer 1, a composite bonding layer 2, and an auxiliary electrode layer 3, distributed sequentially from bottom to top. The working electrode layer 1 is an ITO flexible film, and the working electrode layer 1 is composited with the auxiliary electrode layer 3 through the composite bonding layer 2.
[0044] The working electrode layer 1 includes a membrane substrate 6 and an ITO conductive layer 7 disposed on the membrane substrate 6. The auxiliary electrode layer 3 includes a flexible substrate 17, a conductive layer 4, and an insulating layer 5 distributed sequentially from bottom to top. The composite bonding layer 2 is located between the ITO conductive layer 7 and the flexible substrate 17. The conductive layer 4 includes a reference electrode 9, a counter electrode 10, electrode rails 11, and rail contacts 12 disposed on the flexible substrate 17. There are two electrode rails 11 and two rail contacts 12, and the rail contacts 12 are connected to one end of the electrode rails 11. The end of one electrode rail 11 away from the rail contacts 12 is connected to the reference electrode 9, and the end of the other electrode rail 11 away from the rail contacts 12 is connected to the counter electrode 10. The rail contacts 12 are used to connect to an electrochemical workstation (not shown in the figure). The flexible substrate 17 has an electrolytic cell cavity 13 and a contact area 14, which are located outside the coverage of the insulating layer 5, which covers the electrode rail 11. The reference electrode 9 and the counter electrode 10 are both located within the electrolytic cell cavity 13, and the two rail contacts 12 are both located within the contact area 14.
[0045] The flexible substrate 17 has a hollowed-out circular region 15 that penetrates the entire auxiliary electrode layer 3 within the electrolytic cell cavity 13. The flexible substrate 17 also has a hollowed-out square region 16 that penetrates the auxiliary electrode layer 17 within the contact area 14. The hollowed-out square region 16 is located between two guide rail contacts 12. The area of the working electrode layer 1 opposite to the hollowed-out circular region 15 is the ITO working electrode 8, and the area of the working electrode layer 1 opposite to the hollowed-out square region 16 is the contact of the ITO working electrode 8.
[0046] This embodiment also provides a method for fabricating an electrochemical ITO integrated flexible electrode, comprising the following steps:
[0047] Any of polyethylene terephthalate (PET), polyimide, or polyethylene can be used as the membrane substrate 6 and the flexible substrate 17. In this embodiment, PET is selected as the membrane substrate 6 and the flexible substrate 17. The membrane substrate 6 and the flexible substrate 17 are washed sequentially with ethanol and deionized water, respectively, and then dried for later use. The thickness of the membrane substrate 6 and the flexible substrate 17 can be 50-200 μm; in this embodiment, the thickness of both the membrane substrate 6 and the flexible substrate 17 is 120 μm.
[0048] The film substrate 6 is placed in a magnetron sputtering device or an electron beam evaporation process device, and an ITO conductive layer 7 is deposited on the film substrate 6. The thickness of the ITO conductive layer 7 can be 50-200nm. In this embodiment, the thickness of the ITO conductive layer 7 is 100nm, and the sheet resistance is ≤10Ω / □. The film substrate 6 and the ITO conductive layer 7 form an ITO flexible film.
[0049] Conductive ink is printed onto a flexible substrate 17 using screen printing to form a reference electrode 9, a counter electrode 10, an electrode rail 11, and a rail contact 12. These components together form a conductive layer 4. After the conductive layer 4 dries, insulating ink is printed onto it to form an insulating layer 5. An electrolytic cell cavity region 13 and a contact region 14 are formed on the flexible substrate 17 outside the area covered by the insulating layer 5. The flexible substrate 17, conductive layer 4, and insulating layer 5 together form an auxiliary electrode sheet layer 3. The thickness of the conductive layer 4 can be 5-20 μm; in this embodiment, it is 12 μm thick. The electrode rail 11 has a width of 0.8 mm, and the rail contact 12 has dimensions of length × width = 4 mm × 2 mm. The insulating layer 5 covers the electrode rail 11. The reference electrode 9 and counter electrode 10 are located within the electrolytic cell cavity region 13, and the rail contact 12 is located within the contact region 14. In this embodiment, the reference electrode 9 is an Ag / AgCl electrode, and the counter electrode 10 is a carbon electrode.
[0050] A circular perforated area 15, with a diameter of 4 mm, is stamped out on the insulating layer 5. The circular perforated area 15 penetrates the entire auxiliary electrode layer 3 and is located within the electrolytic cell cavity region 13. A square perforated area 16, with dimensions identical to the guide rail contact piece 12, is stamped out on the flexible substrate 17. The square perforated area 16 penetrates the entire auxiliary electrode layer 3 and is located within the contact piece region 14, specifically between the two guide rail contacts 12.
[0051] An ITO flexible film is used as the working electrode layer 1. The working electrode layer 1 is bonded to the flexible substrate 17 of the auxiliary electrode layer 3 using either ethylene-vinyl acetate copolymer hot melt adhesive or polyamide hot melt adhesive. In this embodiment, ethylene-vinyl acetate copolymer hot melt adhesive is used. The area of the working electrode layer 1 opposite to the hollowed-out circular area 15 is the ITO working electrode 8, and the area on the working electrode layer 1 opposite to the hollowed-out square area 16 is the contact patch of the ITO working electrode 8.
[0052] The working electrode layer 1 and the auxiliary electrode layer 3, which are bonded together, are hot-pressed together using a hot press. The hot-pressing temperature can be 80-150℃, the pressure can be 0.5-2MPa, and the time can be 5-10 minutes. In this embodiment, the hot-pressing temperature is 115℃, the pressure is 1.2MPa, and the time is 7.5 minutes. After hot-pressing, the mixture is held at 60-80℃ and 0.5-1MPa for 1-3 minutes to form a composite bonding layer 2 of ethylene-vinyl acetate copolymer hot melt adhesive. The thickness of the composite bonding layer 2 can be 20-100μm; in this embodiment, the thickness of the composite bonding layer 2 is 60μm. The composite material is then cut to obtain the electrochemical ITO integrated flexible electrode.
[0053] Performance testing
[0054] For Example 1, the following performance tests were performed:
[0055] The electrochemical ITO integrated electrode prepared in Example 1 was used for cyclic voltammetry of electrochemical potassium ferricyanide: the electrode was inserted into the electrode interface of the Chenhua electrochemical workstation (CHI660E), and cyclic voltammetry (CV) was used for detection. 5 mM potassium ferricyanide and 0.1 M PBS buffer solution (pH 7.4) were added dropwise to the electrode electrolysis cell chamber, and CV scans were performed. Figure 4 As shown.
[0056] In conjunction with Example 1 and Figure 4 As can be seen, the electrochemical ITO integrated electrode prepared in Example 1 exhibits good electrochemical reversibility. This is likely because the ITO conductive layer with the aforementioned thickness and sheet resistance, deposited via magnetron sputtering or electron beam evaporation, reduces ohmic losses in the electrode itself, ensuring rapid electron transfer on the electrode surface. This helps to narrow the potential difference between redox peaks, thus improving reversibility. ITO exhibits excellent chemical stability within common electrochemical windows, is not prone to corrosion or surface oxidation, reduces side reactions and electrode degradation, and allows for reproducible reactions, further supporting reversible reactions. The working electrode sheet is exposed in a hollowed-out circular region to form the ITO working electrode, ensuring a consistent electrochemical active area and avoiding edge effects or uneven current distribution, thereby improving reaction reversibility.
[0057] The auxiliary electrode sheet integrates the reference electrode (Ag / AgCl), counter electrode (carbon electrode), electrode rails, and rail contacts, all components screen-printed on the same flexible substrate. This design places all electrodes within closely adjacent electrolytic cell chambers, reducing solution resistance and connection impedance found in conventionally separated electrodes. The reference electrode (Ag / AgCl) provides a stable reference potential, while the counter electrode (carbon electrode) is electrochemically inert, together ensuring potential control and reaction equilibrium at the working electrode. An insulating layer covers the conductive layer, but the electrolytic cell chambers expose the working electrode, reference electrode, and counter electrode, while the electrode rails are located outside the chambers. This layout prevents short circuits and current leakage, while ensuring a uniform electric field distribution and reducing stray current interference. The fact that both the reference and counter electrodes are located within the chambers ensures the stability of the reaction system.
[0058] The contact area and rail contact of the ITO working electrode are located outside the insulation layer coverage area, which realizes low-resistance electrical connection, reduces external contact impedance, and is conducive to fast and stable signal transmission.
[0059] The aforementioned membrane substrates and flexible substrates possess excellent thermoplasticity and chemical inertness, do not participate in reactions in electrochemical environments, and avoid interface contamination.
[0060] The aforementioned hot-pressing lamination conditions and post-lamination processing conditions are designed based on material properties, helping to avoid thermal damage to the substrate, ensuring a strong bond between electrode layers, and maintaining electron transfer efficiency. Holding the hot-pressed lamination at the aforementioned temperature and pressure for a period of time eliminates internal stress and microbubbles, ensuring uniform distribution of the adhesive layer and forming a tight, defect-free interface. Therefore, all components of the electrochemical ITO integrated flexible electrode of this application are integrated on a flexible substrate, reducing wiring and assembly errors of traditional electrodes and making the electrode more stable during testing. Especially in dynamic applications, it can buffer stress and maintain consistent electrochemical performance.
[0061] It should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and are not intended to limit it. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solution of this utility model without departing from the spirit and scope of the technical solution of this utility model, and all such modifications or substitutions should be covered within the scope of the claims of this utility model.
Claims
1. An electrochemical ITO integrated flexible electrode, characterized in that, The system comprises, from bottom to top, a working electrode sheet (1), a composite bonding sheet (2), and an auxiliary electrode sheet (3). The working electrode sheet (1) includes a membrane substrate (6) and an ITO conductive layer (7) disposed on the membrane substrate (6). The auxiliary electrode sheet (3) includes, from bottom to top, a flexible substrate (17), a conductive layer (4), and an insulating layer (5). The flexible substrate (17) is bonded to the ITO conductive layer (7) through the composite bonding sheet (2). The flexible substrate (17) is provided with an electrolytic cell cavity region (13) and a contact area (14). The electrolytic cell cavity region (13) Both the contact area (14) and the contact area (5) are located outside the coverage of the insulating layer (5). The flexible substrate (17) is provided with a hollow circular area (15) and a hollow square area (16) that penetrate the auxiliary electrode sheet (3). The hollow circular area (15) is located in the electrolytic cell cavity area (13), and the hollow square area (16) is located in the contact area (14). The area of the working electrode sheet (1) opposite to the hollow circular area (15) is the ITO working electrode (8), and the area of the working electrode sheet (1) opposite to the hollow square area (16) is the contact of the ITO working electrode (8).
2. The electrochemical ITO integrated flexible electrode according to claim 1, wherein, The conductive layer (4) includes a reference electrode (9), a counter electrode (10), an electrode rail (11), and a rail contact (12) disposed on a flexible substrate (17). The reference electrode (9) and the counter electrode (10) are both connected to the electrode rail (11). The rail contact (12) is connected to the end of the electrode rail (11). The insulating layer (5) covers the electrode rail (11). The reference electrode (9) and the counter electrode (10) are located in the electrolytic cell cavity area (13). The rail contact (12) is located in the contact area (14).
3. The electrochemical ITO integrated flexible electrode according to claim 1, wherein, The membrane substrate (6) is made of any one of polyethylene terephthalate, polyimide or polyethylene.
4. The electrochemical ITO integrated flexible electrode according to claim 3, wherein, The thickness of the film substrate (6) is 50-200 μm, and the thickness of the ITO conductive layer (7) is 50-200 nm.
5. The electrochemical ITO integrated flexible electrode according to claim 4, wherein, The flexible substrate (17) is made of the same material and has the same dimensions as the membrane substrate (6).
6. The electrochemical ITO integrated flexible electrode according to claim 1, wherein, The composite adhesive layer (2) is an ethylene-vinyl acetate copolymer hot melt adhesive layer or a polyamide hot melt adhesive layer, and the thickness of the composite adhesive layer (2) is 20-100 μm.
7. The electrochemical ITO integrated flexible electrode according to claim 1, wherein, The thickness of the conductive layer (4) is 5-20 μm.