Ultramicro electrode and preparation method and surface updating method thereof
By using flexible tubes and easy melting paraffin in ultra -micro -electrodes, the problem of cumbersome operation of traditional ultra -micro -electrode surface updates was solved, and the simplification of the electrode surface update and the flexibility of the electrode shape were realized.
Patent Information
- Application Number
- CN202411619696.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-13
- Publication Date
- 2025-01-24
AI Technical Summary
The existing ultramicro electrode needs to be updated after use for a period of time. The traditional method requires polishing and polishing by sandpaper. The operation is cumbersome and the electrode shape cannot be flexibly changed.
Flexible tubes are used to replace glass capillary tubes, easy-melting and easy-to-solidify paraffin wax is used to replace epoxy resin, and the electrode surface is updated by cutting the flexible tube to achieve flexible electrode shapes.
It simplifies the ultramicroelectrode surface updating operation, improves the simplicity and speed of the operation, and makes the electrode shape flexible and suitable for a variety of electrode materials.
Smart Images
Figure CN119361246A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of ultramicroelectrodes, and in particular to an ultramicroelectrode and a preparation method and a surface renewal method thereof. Background Art
[0002] Ultramicroelectrodes usually refer to electrodes with an electrode diameter of less than 100 μm. They are widely used in electrochemical research because of their fast electrochemical reaction response speed, ability to effectively eliminate IR drop (IR drop) and significantly increase the steady-state limiting diffusion current. Existing ultramicroelectrodes usually include a glass capillary, an electrode wire disposed in the glass capillary, and a sealing body, which wraps the electrode wire to form a seal. Among them, the material of the electrode wire includes carbon fiber, metal fiber, alloy fiber, etc., and the sealing material is usually epoxy resin. This ultramicroelectrode needs to be polished by sandpaper to obtain a fresh electrode surface. In actual use, the ultramicroelectrode needs to update the surface after a period of use, and at this time it needs to be polished again, making the operation cumbersome. Summary of the invention
[0003] To solve the above problems, the purpose of the embodiments of the present application includes providing an ultramicroelectrode and a preparation method and a surface renewal method thereof to simplify the ultramicroelectrode surface renewal operation.
[0004] In a first aspect, the present application provides a method for preparing an ultramicroelectrode, comprising the following steps:
[0005] After one end of the electrode wire and one end of the current collector are connected, they are inserted into the flexible tube, and a gap is formed circumferentially between the electrode wire, the current collector and the inner wall of the flexible tube. The flexible tube is in the shape of a dropper, and the flexible tube includes a first end and a second end opposite to each other, and the diameter of the second end is smaller than the diameter of the first end. The free end of the current collector exposes the first end, and the free end of the electrode wire exposes the second end. Liquid paraffin is injected from the first end of the flexible tube until the electrode wire and the current collector in the flexible tube are immersed, and a sealing body is formed after the liquid paraffin solidifies. The second end of the flexible tube is cut so that the electrode wire is flush with the end surface of the flexible tube and the sealing body.
[0006] In the above technical scheme, the glass capillary is replaced by a flexible tube, and the epoxy resin is replaced by paraffin wax which is easy to melt, easy to solidify, and can be melted again after solidification and is easy to cut, so that the preparation method of the ultramicroelectrode in this application is simple to operate and has a high success rate. The prepared ultramicroelectrode can simply use cutting to update the electrode surface, and the electrode shape is flexible and changeable.
[0007] In some embodiments of the present application, the material of the flexible tube includes at least one of polyethylene, polypropylene, polytetrafluoroethylene or polyvinyl chloride. The inner diameter of the flexible tube is 0.4-1 mm. The flexible tube is made of these flexible polymer materials to achieve a variety of regular or irregular electrode shapes.
[0008] In some embodiments of the present application, the flexible tube includes a first portion and a second portion connected to the first portion, the first end is located at the first portion, the second end is located at the second portion, the first portion is cylindrical, and the inner diameter of the second portion gradually decreases in a direction away from the first portion. The second portion is a regular conical shape, or the second portion is an irregular curved shape.
[0009] In the above technical solution, the ultramicroelectrode in the present application can achieve flexible and changeable electrode shapes by simply controlling the shape of the flexible tube.
[0010] In some embodiments of the present application, the electrode wire includes at least one of carbon fiber, gold wire or platinum wire. In the present application, liquid paraffin is used for sealing, and the preparation conditions are mild, so it can be applied to a variety of electrode materials that are stable at room temperature.
[0011] In some embodiments of the present application, the diameter of the electrode wire is 5-60 μm. The preparation method of the present application can be used to prepare ultramicroelectrodes when the diameter of the electrode wire is within a suitable range, and the current passing through the electrode can be ensured to be moderate.
[0012] In some embodiments of the present application, the current collector includes at least one of a copper wire or a tin wire. In the present application, the copper wire or the tin wire can be used as the current collector to complete current transmission.
[0013] In some embodiments of the present application, the electrode wire and the current collector are connected by welding or bonding with a conductive adhesive. Both welding and bonding can be applied to the preparation method of the present application, and a suitable connection method can be selected according to the actual electrode wire and current collector materials.
[0014] In some embodiments of the present application, after connecting one end of the electrode wire to one end of the current collector, the process further includes: cleaning the electrode wire and drying it. By cleaning and removing oil and impurities on the surface of the electrode wire, holes or gaps can be prevented from forming between the electrode wire and the paraffin, which is beneficial to improving the accuracy of the electrochemical signal.
[0015] In a second aspect, the present application provides an ultra-microelectrode prepared by the above-mentioned preparation method. The surface of the ultra-microelectrode provided in the present application is very easy to update, and the shape of the electrode is flexible and changeable.
[0016] In the third aspect, an embodiment of the present application provides a method for surface renewal of the above-mentioned ultramicroelectrode, comprising the following steps: when the above-mentioned ultramicroelectrode needs to be surface renewed after being used for a period of time, the second end of the flexible tube is cut to remove part of the flexible tube, part of the electrode wire and part of the sealing body, and the electrode wire is kept flush with the end faces of the flexible tube and the sealing body, thereby completing the surface renewal of the ultramicroelectrode.
[0017] In the above technical solution, since a flexible tube is used to replace the glass capillary, and paraffin wax which is easy to melt, easy to solidify, and can be melted again after solidification and is easy to cut is used to replace the epoxy resin, the ultramicroelectrode in this application does not need to use the traditional sandpaper grinding and polishing method, but can simply be cut to achieve surface renewal. The operation is simple and fast, and is convenient for practical application. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.
[0019] Figure 1 It is a schematic diagram of the structure of an ultramicroelectrode according to one embodiment of the present application.
[0020] Figure 2 This is a schematic diagram of the structure of an ultramicroelectrode according to another embodiment of the present application.
[0021] Figure 3 This is the cyclic voltammetry curve of the platinum ultramicroelectrode in Example 3 of the present application.
[0022] Description of reference numerals:
[0023] 1-current collector; 2-flexible tube; 21-first part; 21a-first end; 23-second part; 23a-second end; 3-sealing body; 4-connecting part; 5-electrode wire. DETAILED DESCRIPTION
[0024] Hereinafter, the embodiments of the ultramicroelectrode and its preparation method and the surface renewal method of the present application are specifically disclosed with appropriate reference to the accompanying drawings. However, there may be cases where unnecessary detailed descriptions are omitted. For example, there are cases where detailed descriptions of well-known matters and repeated descriptions of actually the same structures are omitted. This is to avoid the following description from becoming unnecessarily lengthy and to facilitate the understanding of those skilled in the art. In addition, the drawings and the following description are provided for those skilled in the art to fully understand the present application and are not intended to limit the subject matter described in the claims.
[0025] Unless otherwise specified, all embodiments and optional embodiments of the present application can be combined with each other to form a new technical solution.
[0026] Unless otherwise specified, all technical features and optional technical features of this application can be combined with each other to form a new technical solution.
[0027] Unless otherwise specified, all steps of the present application may be performed sequentially or randomly, preferably sequentially. For example, a method includes steps (a) and (b), which means that the method may include steps (a) and (b) performed sequentially, or may include steps (b) and (a) performed sequentially. For example, a method may also include step (c), which means that step (c) may be added to the method in any order, for example, the method may include steps (a), (b) and (c), or may include steps (a), (c) and (b), or may include steps (c), (a) and (b), etc.
[0028] In existing research, glass capillaries are usually used in combination with epoxy resin sealing materials to make ultra-microelectrodes. Since the viscosity of epoxy resin before curing is extremely high and its fluidity is poor, it is easy to cause the ultra-fine electrode material to be distorted when wrapping the electrode material filaments. At the same time, the epoxy resin cures quickly and is irreversible, so the success rate of epoxy resin curing and sealing is low. At the same time, epoxy resin curing and sealing requires sandpaper polishing to obtain a fresh electrode surface, and the electrode needs to be renewed after a period of use. At this time, it needs to be polished again, which brings trouble to actual use. In addition, due to the characteristics of the sealing material, the shape of the electrode cannot be flexibly changed.
[0029] Based on this, an embodiment of the present application provides a method for preparing an ultramicroelectrode. The preparation method is simple to operate and has a high success rate. The surface of the prepared ultramicroelectrode can be easily updated, and the shape of the electrode can be flexible and changeable.
[0030] Figure 1 This is a schematic diagram of the structure of the ultramicroelectrode provided in one embodiment of the present application. Figure 1 The method for preparing the ultramicroelectrode provided in the present application comprises the following steps:
[0031] S110, connect one end of the electrode wire 5 and one end of the current collector 1 and insert them into the flexible tube 2, and form a gap circumferentially between the electrode wire 5, the current collector 1 and the inner wall of the flexible tube 2. The flexible tube 2 is in the shape of a dropper, and the flexible tube 2 includes a first end 21a and a second end 23a opposite to each other, and the diameter of the second end 23a is smaller than the diameter of the first end 21a. The free end of the current collector 1 exposes the first end 21a, and the free end of the electrode wire 5 exposes the second end 23a.
[0032] In some embodiments, the electrode wire 5 may be carbon fiber, gold wire or platinum wire. The diameter of the electrode wire 5 is 5-60 μm, for example, 5 μm, 10 μm, 20 μm, 30 μm, 50 μm, 60 μm, etc.
[0033] In some embodiments, the current collector 1 may be a copper wire or a tin wire. Typically, the diameter of the current collector 1 is greater than the diameter of the electrode wire 5, for example, it may be 0.1 to 0.2 mm.
[0034] In some embodiments, the electrode wire 5 and the current collector 1 are connected via a connecting portion 4 , which may be connected by welding, such as spot welding, and the connecting portion 4 is a welding point; or they may be bonded by conductive adhesive, and the connecting portion 4 is a cured conductive adhesive.
[0035] In some embodiments, after connecting the electrode wire 5 and the current collector 1, the method further includes: cleaning and drying the electrode wire 5. As an example, the electrode wire 5 is cleaned with acetone and ultrapure water respectively to remove oil and impurities on the surface of the electrode wire 5, and then dried under an infrared lamp.
[0036] In some embodiments, the material of the flexible tube 2 can be a polymer flexible material such as polyethylene, polypropylene, polytetrafluoroethylene or polyvinyl chloride. The shape of the dropper-shaped flexible tube 2 can be regular or irregular.
[0037] In some embodiments, the inner diameter of the flexible tube 2 may be 0.4-1 mm.
[0038] In some embodiments, the dropper-shaped flexible tube 2 includes a first portion 21 and a second portion 23 connected to the first portion 21, the first end 21a is located at the first portion 21, the second end 23a is located at the second portion 23, the first portion 21 is generally in a regular cylindrical shape, and the inner diameter of the second portion 23 gradually decreases in a direction away from the first portion 21. The diameter of the first portion 21 may be 0.7 to 1 mm. The inner diameter of the second portion 23 may not exceed 0.5 mm, for example, 0.4 mm.
[0039] In some embodiments, the second portion 23 is substantially in the shape of a regular cone or a truncated cone.
[0040] In other embodiments, the second portion 23 may be an irregular random shape. Figure 2 The second portion 23 is in a curved shape, and the angle between the second portion 23 and the first portion 21 is approximately 90°, so that the flexible tube 2 is approximately L-shaped, forming a Luggin capillary shape.
[0041] It should be noted that the end of the current collector 1 away from the electrode wire 5 is exposed from the first end 21a, in order to facilitate the subsequent connection of the current collector 1 to an external test instrument and fix the ultra-microelectrode. The end of the electrode wire 5 away from the current collector 1 is exposed from the second end 23a, in order to ensure that the end face of the electrode wire 5 can be kept bare in the subsequent application of the ultra-microelectrode.
[0042] S120, injecting liquid paraffin from the first end 21a of the flexible tube 2 until the electrode wire 5 and the current collector 1 in the flexible tube 2 are immersed, and forming a sealing body 3 after the liquid paraffin is solidified.
[0043] In some embodiments, sufficient paraffin wax can be melted in a clean container to obtain liquid paraffin wax with good fluidity and no bubbles. After being injected into the flexible tube 2, it is cooled and solidified at room temperature to form the sealing body 3.
[0044] It should be noted that, during the process of injecting liquid paraffin, it is necessary to ensure that the electrode wire 5 cannot be twisted. In addition, the electrode wire 5 and the current collector 1 should be located on the center line of the flexible tube 2 as much as possible.
[0045] S130 , cutting the second end 23 a of the flexible tube 2 so that the electrode wire 5 is flush with the end surfaces of the flexible tube 2 and the sealing body 3 .
[0046] Since the material of the flexible tube 2 is a flexible polymer material, and the material of the sealing body 3 is paraffin which is easy to melt and solidify and can be melted again after solidification and is easy to cut, the electrode wire 5 can be directly cut with sharp scissors or blades to make the end faces of the flexible tube 2 and the sealing body 3 flush, and the end face of the electrode wire 5 is exposed, thereby obtaining an ultramicroelectrode.
[0047] In addition, an embodiment of the present application also provides a method for renewing the surface of the above-mentioned ultramicroelectrode, comprising the following steps: when the surface of the ultramicroelectrode needs to be renewed after being used for a period of time, the second end 23a of the flexible tube 2 is cut to remove part of the flexible tube 2, part of the electrode wire 5 and part of the sealing body 3, and the electrode wire 5 is kept flush with the end faces of the flexible tube 2 and the sealing body 3, thereby completing the surface renewal of the ultramicroelectrode.
[0048] Since the material of the flexible tube 2 is a flexible polymer material, and the material of the sealing body 3 is paraffin which is easy to melt and solidify and can be melted again after solidification and is easy to cut, the surface renewal of the ultramicroelectrode can be achieved by directly using sharp scissors or blades to cut off a part from the second end 23a.
[0049] The technical solution of the present application is described in detail below in conjunction with specific embodiments.
[0050] Example 1
[0051] See also Figure 1 This embodiment provides a carbon fiber ultrafine electrode. The electrode wire 5 is a carbon fiber wire with a diameter of 6 μm, the current collector 1 is a copper wire, the second part 23 of the flexible tube 2 is a regular cone, and the material of the flexible tube 2 is polypropylene. The preparation method of the carbon fiber ultrafine working electrode includes the following steps:
[0052] S110, the electrode wire 5 and the current collector 1 are bonded together by conductive glue, and placed at room temperature to wait for the conductive glue to solidify to form the connecting portion 4. After the conductive glue is solidified, the electrode wire 5 is ultrasonically cleaned with acetone and ultrapure water respectively to remove oil and impurities on the surface of the electrode wire 5, and dried for use. The electrode wire 5 connected to the current collector 1 is placed in a dropper-shaped flexible tube 2, so that the end of the electrode wire 5 away from the current collector 1 is exposed from the second end 23a of the flexible tube 2, and the end of the current collector 1 away from the electrode wire 5 is exposed from the first end 21a of the flexible tube 2.
[0053] S120, melt enough paraffin in a clean container to obtain liquid paraffin with good fluidity and no bubbles. Slowly inject the liquid paraffin from the first end 21a of the flexible tube 2 until the current collector 1 and the electrode wire 5 are immersed, so that the electrode wire 5 is sealed, and at the same time, the flexible tube 2 is filled with paraffin, and the paraffin is solidified at room temperature to form a sealing body 3.
[0054] S130, using sharp scissors to cut the second end 23a of the cured flexible tube 2, so that the end surface of the electrode wire 5 is exposed, and the end surfaces of the electrode wire 5, the flexible tube 2 and the sealing body 3 are roughly flush, so as to obtain a carbon fiber ultramicroelectrode.
[0055] Example 2
[0056] See also Figure 1 This embodiment provides a gold ultramicroelectrode, the electrode wire 5 is a gold wire with a diameter of 30 μm, and the current collector 1 is a tin wire. The preparation method is substantially the same as that of embodiment 1, except that:
[0057] In step S110 , the current collector 1 is melted by spot welding, and then one end of the electrode wire 5 is placed on the welding spot. After cooling, the connection between the electrode wire 5 and the current collector 1 is completed.
[0058] Example 3
[0059] See also Figure 2 This embodiment provides a platinum ultramicroelectrode, wherein the electrode wire 5 is a platinum wire with a diameter of 30 μm, the current collector 1 is a tin wire, the first portion 21 of the flexible tube 2 is a regular cylindrical shape, and the second portion 23 is an irregular cone bent into a roughly L-shaped shape, with a sharp thin end, forming a Luggin capillary shape. The preparation method of the platinum ultramicro reference electrode is substantially the same as that of Example 2.
[0060] The platinum ultramicroelectrode in Example 3 was used as the working electrode, a platinum sheet with an area of about 1 square centimeter was used as the counter electrode, a reversible hydrogen electrode (RHE) was used as the reference electrode, and 0.5 mol / L dilute sulfuric acid was used as the electrolyte to perform cyclic voltammetry scanning with a scanning speed of 10 mV / s and a scanning voltage range of 0.05 to 1.3 V (vs. RHE). Before starting the scan, the electrolyte was purged with high-purity argon (99.99%) for 10 minutes to remove oxygen in the electrolyte, and then the scan was started to obtain a complete cyclic voltammetry curve of the platinum ultramicroelectrode. Figure 3 The cyclic voltammetry curve of the platinum ultramicroelectrode in Example 3 is shown in FIG. Figure 3 It can be seen that the platinum ultramicroelectrode has good electrochemical activity.
[0061] The embodiments described above are part of the embodiments of the present application, rather than all of the embodiments. The detailed description of the embodiments of the present application is not intended to limit the scope of the present application for protection, but merely represents the selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application.
Claims
1. A method for preparing an ultramicroelectrode, characterized in that: The following steps are involved: Connect one end of the electrode wire and one end of the current collector and insert them into the flexible tube, wherein a gap is formed circumferentially between the electrode wire, the current collector and the inner wall of the flexible tube; wherein the flexible tube is dropper-shaped and comprises a first end and a second end opposite to each other, wherein the diameter of the second end is smaller than the diameter of the first end; the free end of the current collector exposes the first end, and the free end of the electrode wire exposes the second end; Injecting liquid paraffin from the first end of the flexible tube until the electrode wire and the current collector in the flexible tube are immersed, and forming a sealing body after the liquid paraffin is solidified; The second end of the flexible tube is cut so that the electrode wire is flush with the end surfaces of the flexible tube and the sealing body.
2. The preparation method according to claim 1, characterized in that: The material of the flexible tube includes at least one of polyethylene, polypropylene, polytetrafluoroethylene or polyvinyl chloride; And / or, the inner diameter of the flexible tube is 0.4-1 mm.
3. The preparation method according to claim 1 or 2, characterized in that: The flexible tube comprises a first portion and a second portion connected to the first portion, the first end is located in the first portion, the second end is located in the second portion, the first portion is cylindrical, and the inner diameter of the second portion gradually decreases in a direction away from the first portion; The second portion is in a regular conical shape; or, the second portion is in a curved shape.
4. The preparation method according to claim 1, characterized in that: The electrode wire includes at least one of carbon fiber, gold wire or platinum wire.
5. The preparation method according to claim 1 or 4, characterized in that: The diameter of the electrode wire is 5 to 60 μm.
6. The preparation method according to claim 1, characterized in that: The current collector includes at least one of copper wire or tin wire.
7. The preparation method according to claim 1, characterized in that: The electrode wire and the current collector are connected by welding or bonding with a conductive adhesive.
8. The preparation method according to claim 1 or 7, characterized in that: After one end of the electrode wire is connected to one end of the current collector, the method further includes: cleaning and drying the electrode wire.
9. An ultramicroelectrode, characterized in that: The compound is prepared by the preparation method according to any one of claims 1 to 8.
10. A method for surface renewal of an ultramicroelectrode as claimed in claim 9, characterized in that: The following steps are involved: When the surface of the ultramicroelectrode needs to be renewed after being used for a period of time, the second end of the flexible tube is cut to remove part of the flexible tube, part of the electrode wire and part of the sealing body, and the electrode wire is kept flush with the end faces of the flexible tube and the sealing body, thereby completing the surface renewal of the ultramicroelectrode.