Two-channel ultra-microelectrode for electrochemical analysis and manufacturing method therefor

Abstract

The present invention relates to a two-channel ultra-microelectrode for electrochemical analysis and a manufacturing method therefor.

Description

Two-channel ultra-microelectrode for electrochemical analysis and method for manufacturing the same

[0001] The present invention relates to a two-channel ultra-fine electrode for electrochemical analysis, which can be utilized not only as an electrode for a scanning electrochemical microscope but also as a specimen for micro-surface analysis using a scanning electrochemical microscope, and a method for manufacturing the same.

[0002] As research on copper as a catalyst for improving the lifespan of secondary batteries and reducing carbon dioxide emissions has progressed, understanding of these electrochemical phenomena is increasing.

[0003] The lifespan of secondary batteries is affected by the deformation of local areas caused by volume expansion due to the inflow and outflow of lithium ions during charging and discharging, the formation of dead zones (inactive areas) due to excessive SEI (solid electrolyte interface) formation, and the degree of activation of the generated gas during the reduction reaction of copper catalysts for carbon dioxide reduction being concentrated at grain boundaries. Therefore, there is a growing need for analysis and measurement of electrochemical reactions in local areas that can analyze the aforementioned phenomena in order to improve the lifespan of secondary batteries.

[0004] For these two-dimensional electrochemical analyses, research on electrochemical processes using a scanning electrochemical microscope (SEM) has been actively conducted recently through the development of new electrodes.

[0005] Scanning electrochemical microscopy has excellent spatial resolution by quantitatively measuring local electrical activity using ultra-electrodes.

[0006] To improve the spatial resolution of these scanning electrochemical microscopes, smaller area ultra-microelectrodes are required to measure local electrochemical reactions.

[0007] Ultra-fine electrodes can be used not only as probes for scanning electrochemical microscope probes, but also as substrates because they can themselves become reaction surfaces where electrochemical reactions occur. In order to use these reaction electrodes themselves and observe various electrochemical reactions, it is necessary to manufacture ultra-fine electrodes for a wider variety of metals in addition to platinum and gold, which have been mainly used in the past.

[0008] As shown in Fig. 20, it is known that a microelectrode (23) is generally manufactured by applying a tension force to both ends of a glass tube (21) into which a conductive wire (22) is inserted, heating the center using a laser or the like to form a necking in the center, and then further heating using a laser or the like while applying a tension force to cause the conductive wire (22) and the inside of the glass tube (21) to come into close contact and cause a break in the center.

[0009] At this time, as the center where the necking is formed is heated and the temperature of the conductive wire (22) located at the center increases to near the melting point, coarse crystal grains are formed on the surface of the conductive wire (22) located at the center of the glass tube (21), and when the ultra-fine electrode (23) is used as a measuring substrate, there is a problem in that it is difficult to use it as a substrate for analyzing the fine crystal grains, and in the case of a metal that is oxidized severely by laser heat generation, there is a problem in that it is easily broken by tensile stress when the surface brittleness increases.

[0010] In addition, in general, the ultra-fine electrodes used in scanning electrochemical microscopes have a problem in that they have difficulty in performing various electrochemical analyses because only one surface of the conductive wire (22) for performing electrochemical analysis is formed, or even if multiple electrode surfaces are formed, the electrode surfaces are formed using the same platinum wire.

[0011] The purpose of the present invention is to solve the above-mentioned problems, and to provide a two-channel ultra-fine electrode for electrochemical analysis having a buried layer formed thereon, which can be used not only as a probe of a scanning electrochemical microscope probe but also as a specimen for analyzing microcrystals, and can perform electrochemical analysis on multiple surfaces simultaneously, and a method for manufacturing the same.

[0012] The purpose of the present invention is not limited to the purposes mentioned above, and other purposes not mentioned can be clearly understood from the description below.

[0013] In order to achieve the above-described object, a method for manufacturing a two-channel ultra-fine electrode for electrochemical analysis according to one aspect of the present invention comprises the steps of: preparing an insulating member having two hollows formed along a longitudinal direction; preparing a conductive wire made of a conductive material; inserting the conductive wire into the hollows; applying heat and an external force to the insulating member into which the conductive wire is inserted to elongate the insulating member and the conductive wire so that the central portion of the insulating member becomes thin, and causing the central portions of the insulating member and the conductive wire to be fractured, thereby manufacturing a semi-finished product; etching the conductive wire located on the fracture surface side of the semi-finished product to form two grooves having a predetermined depth; and electroplating the semi-finished product to form a buried layer in a portion corresponding to each of the two grooves, thereby manufacturing an ultra-fine electrode.

[0014] In order to achieve the above-mentioned object, a two-channel microelectrode method for electrochemical analysis according to another aspect of the present invention comprises: an insulating member having two hollows formed along a longitudinal direction; a conductive wire inserted into the hollows so that a groove having a predetermined depth is formed at one end of the insulating member; and two buried layers formed in an area corresponding to the groove formed at one end of the insulating member and composed of a conductive material.

[0015] The ultra-fine electrode for electrochemical analysis according to the embodiment of the present invention with the above-described configuration and the method for manufacturing the same have the advantage of being able to be used not only as a tip of a scanning electrochemical microscope probe, but also as a specimen of a scanning electrochemical microscope.

[0016] In particular, by forming a conductive buried layer by etching the surface of the conductive wire exposed at the center and then using plating, not only can the type of material constituting the buried layer be changed as needed, but also the formation of a buried layer with fine crystal grains is possible, which has the advantage of increasing usability as a specimen for a scanning electrochemical microscope.

[0017] In addition, since it is possible to form two embedding layers composed of different materials when forming the embedding layer, there is an effect of enabling simultaneous electrochemical analysis of different materials when performing electrochemical analysis using an ultra-fine electrode.

[0018] Figures 1 and 2 are flowcharts showing the order of a method for manufacturing a two-channel ultra-fine electrode for electrochemical analysis according to one embodiment of the present invention.

[0019] Figures 3 to 7 are optical microscope analysis images obtained through optical microscope analysis according to a test example.

[0020] Figures 8 to 12 are images obtained through scanning electron microscope analysis according to a test example.

[0021] Figures 13 to 18 are images obtained through analysis using energy dispersive spectroscopy according to a test example.

[0022] Figure 19 is a drawing showing the results of analyzing the hydrogen generation reaction according to Test Example 2 of the ultra-fine electrode manufactured according to Example 1.

[0023] Figure 20 is a drawing for explaining a method for manufacturing an ultra-fine electrode according to a conventional technology.

[0024] In order to achieve the above-described object, a method for manufacturing a two-channel ultra-fine electrode for electrochemical analysis according to one aspect of the present invention comprises the steps of: preparing an insulating member having two hollows formed along a longitudinal direction; preparing a conductive wire made of a conductive material; inserting the conductive wire into the hollows; applying heat and an external force to the insulating member into which the conductive wire is inserted to elongate the insulating member and the conductive wire so that the central portion of the insulating member becomes thin, and causing the central portions of the insulating member and the conductive wire to be fractured, thereby manufacturing a semi-finished product; etching the conductive wire located on the fracture surface side of the semi-finished product to form two grooves having a predetermined depth; and electroplating the semi-finished product to form a buried layer in a portion corresponding to each of the two grooves, thereby manufacturing an ultra-fine electrode.

[0025] In order to achieve the above-mentioned object, a two-channel microelectrode method for electrochemical analysis according to another aspect of the present invention comprises: an insulating member having two hollows formed along a longitudinal direction; a conductive wire inserted into the hollows so that a groove having a predetermined depth is formed at one end of the insulating member; and two buried layers formed in an area corresponding to the groove formed at one end of the insulating member and composed of a conductive material.

[0026] The advantages and features of the present invention, and the methods for achieving them, will become clearer with reference to the embodiments described in detail below together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms. These embodiments are provided only to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention. Meanwhile, the terminology used in this specification is for the purpose of describing the embodiments and is not intended to limit the present invention. In this specification, the singular includes the plural unless specifically stated otherwise.

[0027]

[0028] Hereinafter, with reference to the drawings, an ultra-fine electrode for electrochemical analysis and a method for manufacturing the same according to embodiments of the present invention will be described.

[0029] In describing a two-channel ultra-fine electrode for electrochemical analysis and a method for manufacturing the same according to embodiments of the present invention, substantially identical components are described with matching reference numerals, and repeated descriptions are omitted for convenience of explanation.

[0030]

[0031] A method for manufacturing a two-channel ultra-fine electrode for electrochemical analysis according to one embodiment of the present invention is a method for manufacturing a two-channel ultra-fine electrode (10) for electrochemical analysis according to another embodiment of the present invention, and includes an insulating member preparation step (S100), a conductive wire preparation step (S200), an insertion step (S300), a semi-finished product manufacturing step (S400), an etching step (S600), and an embedding step (S700).

[0032] According to another embodiment of the present invention, an electrochemical analysis ultra-fine electrode (10) includes an insulating member (100), a conductive wire (200), and a buried layer (300).

[0033] An insulating member (100) having a capillary shape with two hollows formed along the length direction is prepared (S100).

[0034] The insulating member (100) prepared in the insulating member preparation step (S100) may be formed with two hollow portions separated from each other along the length direction.

[0035] The insulating member (100) prepared in the insulating member preparation step (S100) may have two hollow parts with the same diameter along the length direction, but is not limited thereto and may have different diameters.

[0036] The two cavities formed in the insulating member (100) prepared in the insulating member preparation step (S100) may be formed parallel to each other.

[0037] The insulating member (100) prepared in the insulating member preparation step (S100) is not limited to being composed of a material having insulating properties, and may be composed of a glass material, and may be composed of, for example, at least one of borosilicate glass, silicon oxide, and aluminum silicon oxide.

[0038] The inner diameter of the insulating member (100) prepared in the insulating member preparation step (S100) is not limited as long as it is on the order of several to several hundred μm, but may be conveniently 100 to 1000 μm so that it can be smoothly broken in the semi-finished product manufacturing step (S400).

[0039]

[0040] A conductive wire having a diameter smaller than the diameter of the hollow formed along the length direction of the insulating member (100) is prepared (S200).

[0041] The conductive wire (200) prepared in the conductive wire preparation step (S200) is not limited as long as it is composed of a material having conductivity.

[0042] However, when the inventors of the present invention were conducting research and development to complete the present invention, when a copper wire having a diameter of 25 ㎛ or less was used as a conductive wire (200), there was a problem that when a semi-finished product (H) was manufactured in the semi-finished product manufacturing step (S400), the oxidation of the conductive wire (200) located on the fracture surface of the semi-finished product (H) was so severe that the end of the conductive wire (200) where oxidation occurred broke off.

[0043] Accordingly, the conductive wire (200) prepared in the conductive wire preparation step (S200) may be composed of a material having conductivity, but may be composed of a material having relatively superior oxidation resistance compared to copper.

[0044] For example, the conductive wire (200) prepared in the conductive wire preparation step (S200) may be composed of a material having relatively excellent oxidation resistance and less high-temperature corrosion than copper, including at least one of nickel (Ni) and chromium (Cr).

[0045] Preferably, the conductive wire (200) prepared in the conductive wire preparation step (S200) may be composed of stainless steel containing at least one of nickel (Ni) and chromium (Cr).

[0046] More preferably, the conductive wire (200) prepared in the conductive wire preparation step (S200) may be composed of austenitic stainless steel containing nickel (Ni) and chromium (Cr), and most preferably, the conductive wire (200) prepared in the conductive wire preparation step (S200) may be composed of any one of stainless steel 304 and stainless steel 316 containing nickel (Ni) and chromium (Cr), and may have relatively superior oxidation resistance than copper.

[0047] If the conductive wire (200) prepared in the conductive wire preparation step (S200) is composed of stainless steel containing nickel and chromium, even if the diameter of the conductive wire (200) is 25 ㎛ or less, the conductive wire (200) located on the fracture surface of the semi-finished product (H) manufactured in the semi-finished product manufacturing step (S400) can be prevented from breaking even when exposed to high temperature and tensile deformation is applied.

[0048] The conductive wire (200) prepared in the conductive wire preparation step (S200) may have a diameter of a hollow space formed along the length direction of the insulating member (100) prepared in the insulating member preparation step (S100) so that it can be inserted into the hollow space of the insulating member (100) in the insertion step (S300), i.e., a diameter less than or equal to the inner diameter of the insulating member (100).

[0049] In addition, the lower limit of the diameter of the conductive wire (200) prepared in the conductive wire preparation step (S200) is not limited, but since the manufacture of a conductive wire (200) having a diameter of 10 ㎛ or less is currently somewhat difficult in terms of technology, the diameter of the conductive wire (200) prepared in the conductive wire preparation step (S200) may exceed 10 ㎛.

[0050] The conductive wire preparation step (S200) may be a step of preparing two conductive wires (200) to insert the conductive wires (200) into two hollow holes formed in the insulating member (100) in the insertion step (S300).

[0051]

[0052] In the insulating member preparation step (S100), the conductive wire (200) prepared in the conductive wire preparation step (S200) is inserted into a hollow space formed along the length of the insulating member (100) prepared in the insulating member preparation step (S300).

[0053] The insertion step (S300) may be a step of inserting a conductive wire (200) into each of two hollows formed in the insulating member (100) to obtain an insulating member (100) in which a conductive wire (200) is inserted into each of the two hollows. Accordingly, the insulating member (100) obtained in the insertion step (S300) may have two conductive wires (200) inserted along the longitudinal direction.

[0054] In the insertion step (S300), the conductive wires (200) inserted into each of the two hollows formed in the insulating member (100) may be composed of different materials, but are not limited to being composed of the same material.

[0055]

[0056] In the insertion step (S300), heat and external force are applied to an insulating member (100) into which two conductive wires (200) are inserted to manufacture a semi-finished product (S400).

[0057] The semi-finished product manufacturing step (S400) may be a step of manufacturing a semi-finished product (H) by heating an insulating member (100) into which two conductive wires (200) are inserted, applying a tensile force to the insulating member (100) into which the conductive wires (200) are inserted, so that the center of the insulating member (100) becomes relatively thinner than one end and the other end, and causing a break in the center of the insulating member (100) and the conductive wires (200).

[0058] Accordingly, the surfaces of two conductive wires (200) may be exposed on one side of the semi-finished product (H) formed when the insulating member (100) and the conductive wire (200) are broken in the semi-finished product manufacturing step (S400).

[0059] The semi-finished product manufacturing step (S400) may be a step of manufacturing a semi-finished product (H) by heating the conductive wire (200) and the insulating member (100) and applying a tensile force in one direction and the other direction to one end and the other end of the insulating member (100) into which the conductive wire (200) is inserted, thereby elongating the insulating member (100) into which the conductive wire (200) is inserted, thereby making the center of the insulating member (100) thinner and causing the center of the insulating member (100) and the conductive wire (200) to break.

[0060] The semi-finished product manufacturing step (S400) applies tensile force in one direction and the other direction to one end and the other end of the insulating member (100) into which the conductive wire (200) is inserted, respectively, so that the center of the insulating member (100) becomes thinner, and then while heating the thinned center using a laser, tensile force is continuously applied to one end and the other end of the insulating member (100) so that the center of the insulating member (100) and the conductive wire (200) are broken.

[0061] When manufacturing a semi-finished product in the semi-finished product manufacturing step (S400), by heating the conductive wire (200) and the insulating member (100) and applying a tensile force in one direction and the other direction to one end and the other end of the insulating member (100) into which the conductive wire (200) is inserted, the inner surface of the insulating member (100) and the outer surface of the conductive wire (200) can be brought into close contact.

[0062] Accordingly, the inner diameter of the insulating member (100) and the diameter of the conductive wire (200) included in the ultra-fine electrode (10) manufactured according to one embodiment of the present invention may correspond to each other.

[0063]

[0064] In the semi-finished product manufacturing step (S400), a conductive wire (200) located on the cross-section side of the semi-finished product (H) manufactured is etched to form a groove (G) having a predetermined depth (S600).

[0065] The etching step (S600) may be a step of etching two conductive wires (200) inserted into the insulating member (100) so that two grooves (G) having a predetermined depth are formed on the cross-sectional surface of the semi-finished product (H) manufactured in the semi-finished product manufacturing step (S400).

[0066] The etching step (S600) may be to form a groove (G) having a predetermined depth in the semi-finished product (H) by etching two conductive wires (200) exposed on one side of the semi-finished product (H) manufactured in the semi-finished product manufacturing step (S400) in the opposite direction.

[0067] The etching step (S600) may be a step of forming a groove (G) by etching the conductive wire (200) of the semi-finished product (H) manufactured in the semi-finished product manufacturing step (S400) using at least one of wet etching, dry etching, and electrolytic etching.

[0068] For example, in the case of etching a conductive wire (200) by an electrolytic etching method in the etching step (S600), an etching solution is prepared, and the semi-finished product (H) obtained in the semi-finished product manufacturing step (S400) is immersed in the prepared etching solution, and then a voltage is applied to the etching solution, thereby etching two conductive wires (200) and forming two grooves (G) in the semi-finished product (H).

[0069] As the conductive wire (200) is etched in the etching step (S600), two conductive wires (200) may be inserted in a form such that two grooves (G) having a predetermined depth are formed in one end of the insulating member (100).

[0070]

[0071] Two grooves (G) of a semi-finished product (H) obtained in the etching step (S600) are filled with a conductive material to form two filling layers (300), thereby manufacturing an ultra-fine electrode (10) having two channels (S700).

[0072] The embedding step (S700) may be a step of manufacturing an ultra-fine electrode (10) having two channels by plating the semi-finished product (H) obtained in the etching step (S600) and embedding two grooves (G) of the semi-finished product (H) with a conductive material.

[0073] Meanwhile, in the present specification, the ultra-fine electrode (10) having two channels or two channels may mean an ultra-fine electrode (10) that enables simultaneous electrochemical analysis on the surfaces of two buried layers (300) formed when two buried layers (300) are formed and electrochemical analysis is performed.

[0074] The embedding step (S700) may be a step of forming two embedding layers (300) by plating the semi-finished product (H) obtained in the etching step (S600) to form an embedding layer (300) in each area corresponding to the two grooves (G) of the semi-finished product (H).

[0075] The embedding step (S700) can form two embedding layers (300) by repeatedly forming the embedding layer (300) by plating the portion where two grooves (G) are formed in the semi-finished product (H) obtained in the etching step (S600).

[0076] The two embedding layers (300) formed in the embedding step (S700) may be composed of different materials, but are not limited thereto, and are not limited to being composed of the same materials.

[0077] The embedding step (S700) may be a step of forming an embedding layer (300) by embedding a groove (G) of a semi-finished product (H) with a conductive material by preparing a plating solution containing conductive material ions, immersing the semi-finished product in the plating solution, and then applying voltage to the plating solution, but is not limited thereto. It may be a step of forming an embedding layer (300) by an electroless plating method of preparing a plating solution containing conductive material ions, immersing the semi-finished product in the plating solution, and then using a reducing agent to cause reduction of the conductive material.

[0078] In the embedding step (S700), by changing the plating conditions such as the composition of the plating solution, the strength of the current applied to the plating solution, and the time of the current applied to the plating solution as needed, an embedding layer (300) having a microstructure required by the user can be formed, and accordingly, an ultra-fine electrode (10) composed of a conductive material and having a surface having a microstructure required by the user can be manufactured.

[0079] In addition, since two embedding layers (300) composed of different materials can be formed in the embedding step (S700), electrochemical analysis of different materials can be performed simultaneously using the ultra-fine electrode (10) manufactured according to one embodiment of the present invention.

[0080] The embedding step (S700) may include a plating solution preparation step (S710), an immersion step (S720), and a plating step (S720).

[0081] The plating solution preparation step (S710) may be a step for preparing a plating solution for plating a semi-finished product (H) obtained in the etching step (S600).

[0082] The plating solution preparation step (S710) may be a step of preparing a plating solution containing ions of a conductive material for filling a groove (G) formed in a semi-finished product (H) obtained in the etching step (S600).

[0083] The ions of the conductive material included in the plating solution prepared in the plating solution preparation step (S710) may be at least one of copper (Cu), nickel (Ni), tin (Sn), aluminum (Al), iron (Fe), cobalt (Co), zinc (Zn), zirconium (Zr), chromium (Cr), palladium (Pd), silver (Ag), indium (In), and lead (Pb) ions, but are not limited thereto, and any ion of a plating-capable material may be included without limitation.

[0084] Since the ions of the conductive material included in the plating solution prepared in the embedding step (S700) are at least one of copper (Cu), nickel (Ni), tin (Sn), aluminum (Al), iron (Fe), cobalt (Co), zinc (Zn), zirconium (Zr), chromium (Cr), palladium (Pd), silver (Ag), indium (In), and lead (Pb) ions, the embedding layer (300) formed in the embedding step (S700) may be composed of any one selected from the group consisting of copper (Cu), nickel (Ni), tin (Sn), aluminum (Al), iron (Fe), cobalt (Co), zinc (Zn), zirconium (Zr), chromium (Cr), palladium (Pd), silver (Ag), indium (In), and an alloy resulting from a combination of at least two of these.

[0085] For example, when the buried layer (300) formed in the buried step (S700) is composed of an alloy, the buried layer (300) may be composed of an alloy of any one of copper (Cu)-nickel (Ni), tin (Sn)-silver (Ag), nickel (Ni)-iron (Fe), and nickel (Ni)-cobalt (Co), but is not limited thereto, and may be composed of various alloys in which at least two of copper (Cu), nickel (Ni), tin (Sn), aluminum (Al), iron (Fe), cobalt (Co), zinc (Zn), zirconium (Zr), chromium (Cr), palladium (Pd), silver (Ag), and indium (In) are combined as described above.

[0086] The plating solution prepared in the plating solution preparation step (S710) may include ions of a conductive material to fill the groove (G) formed in the semi-finished product (H) obtained in the etching step (S600), and may further include an organic or inorganic additive including at least one of a plating inhibitor, a plating accelerator, and a leveling agent, as needed.

[0087] The plating solution preparation step (S710) can prepare two plating solutions having different compositions to fill two grooves (G) formed in the semi-finished product (H) with different materials.

[0088] The plating solution prepared in the plating solution preparation step (S710) can be one generally used in the plating technology field, and for example, when the conductive material for filling the groove (G) formed in the semi-finished product (H) obtained in the etching step (S600) is copper, the plating solution prepared in the plating solution preparation step (S710) can be prepared by mixing sulfuric acid, copper sulfate, and water to contain copper ions.

[0089] If the conductive material for filling the groove (G) formed in the semi-finished product (H) obtained in the etching step (S600) is nickel, the plating solution prepared in the plating solution preparation step (S710) may include nickel sulfate hexahydrate (NiSO4·6H2O), nickel chloride hexahydrate (NiCl2·6H2O), boric acid (H3BO3), and sodium dodecyl sulfate (SDS) to include nickel ions.

[0090]

[0091] The first plating step (S720) may be a step of immersing the semi-finished product (H) obtained in the etching step (S600) in any one of the plating solutions prepared in the plating solution preparation step (S710) and plating a portion corresponding to any one of the two grooves (G) formed in the semi-finished product (H) to form a buried layer (300).

[0092] In the first plating step (S720), an anode can be immersed in the plating solution prepared in the plating solution preparation step (S710) together with the semi-finished product (H) obtained in the etching step (S600).

[0093] At this time, the oxidation electrode is not limited to those commonly used in the electrochemical field. For example, a copper-containing electrode can be used for copper plating as a soluble electrode, and a nickel ball can be used for nickel plating. In addition, when an insoluble electrode is used as the oxidation electrode, any one of an iridium oxide (IrO2) electrode, an insoluble platinum oxide (PtO2) electrode, a platinum (Pt), and a lead (Pb) electrode can be used.

[0094] The first plating step (S720) may be a step in which a current is applied to a plating solution in which a semi-finished product is immersed to plate a portion corresponding to one of the two grooves (G) formed in the semi-finished product (H) to form one buried layer (300).

[0095] When a current is applied to the plating solution in the first plating step (S720), ions of the conductive material included in the plating solution prepared in the plating solution preparation step (S710) are reduced, so that plating can be performed on the inner surface of the groove (G) formed in the semi-finished product (H) immersed in the plating solution, and accordingly, a buried layer (300) composed of a conductive material can be formed in the groove (G) of the semi-finished product (H).

[0096] The first plating step (S720) may be a step of forming a buried layer (300) by electrically connecting one of the conductive wires (200) inserted into the semi-finished product (H) immersed in the plating solution and the oxidation electrode to an external power source and applying current. At this time, the buried layer (300) may be formed in an area corresponding to a groove (G) located at one end of the conductive wire (200) that is electrically connected to the external power source and to which voltage is applied.

[0097]

[0098] The second plating step (S730) may be a step of immersing a semi-finished product (H) in which one embedded layer (300) is formed in the first plating step (S720) into one of the plating solutions prepared in the plating solution preparation step (710) and applying current to the plating solution to form the embedded layer (300).

[0099] In the second plating step (S730), the oxidation electrode can be immersed in the plating solution together with the semi-finished product (H), and at this time, the oxidation electrode used in the first plating step (720) can be used.

[0100] The second plating step (S730) can form a buried layer (300) in a portion corresponding to one of the two grooves (G) formed in the semi-finished product (H) in which the buried layer (300) was not formed in the first plating step (S720).

[0101] The second plating step (S730) may be a step of forming a buried layer (300) by inserting a conductive wire (200) having one end formed in a groove (G) in which a buried layer (300) is not formed and electrically connecting an oxidation electrode to an external power source and applying current, and at this time, the buried layer (300) may be formed in an area corresponding to the groove (G) located at one end of the conductive wire (200) that is electrically connected to an external power source and to which voltage is applied.

[0102] By using plating solutions having different compositions in the first plating step (S720) and the second plating step (S730), the buried layer (300) can be formed of different materials.

[0103]

[0104] A method for manufacturing an ultra-fine electrode for electrochemical analysis according to one embodiment of the present invention may further include a first polishing step (S500) and a second polishing step (S800).

[0105] The first polishing step (S500) may be performed between the semi-finished product manufacturing step (S400) and the etching step (S600). The semi-finished product (H) manufactured in the semi-finished product manufacturing step (S400) may have a fractured surface that is relatively uneven, as the insulating member (100) and the conductive wire (200) are fractured.

[0106] The first polishing step (S500) may be a step of polishing the fracture surface of the semi-finished product (H) manufactured in the semi-finished product manufacturing step (S400) so that the fracture surface of the semi-finished product (H) becomes flatter. If the fracture surface of the semi-finished product (H) is polished in the first polishing step (S500), the formation of the embedding layer (300) in the embedding step (S700) can be carried out more smoothly.

[0107] The first polishing step (S500) may be a step of polishing the cross-section of the semi-finished product (H) using a mechanical polishing method, but is not limited thereto, and an ion milling method may be used. For example, the cross-section of the semi-finished product (H) may be polished using an ion milling method using at least one of FIB (Focused, Ion Beam) and CP (Cross-section Polisher).

[0108]

[0109] The second polishing step (S800) can be performed after the landfill step (S700).

[0110] The second polishing step (S800) may be a step of polishing the surface on which the embedding layer (300) of the ultra-fine electrode (10) manufactured in the embedding step (S700) is formed.

[0111] In the embedding step (S700), when forming the embedding layer (300) using plating, an unnecessary plating portion (W) may be formed, and as a result, when the ultra-fine electrode (10) is used as a tip of a scanning electrochemical microscope probe or a specimen, electrochemical analysis may not be performed smoothly.

[0112] The second polishing step (S800) may be a step of polishing the surface on which the embedding layer (300) of the ultra-fine electrode (10) manufactured in the embedding step (S700) is formed in order to remove an unnecessarily plated portion (W) formed when forming the embedding layer (300) using plating in the embedding step (S700).

[0113] The second polishing step (S800) can polish the surface on which the embedded layer (300) of the ultra-fine electrode (10) manufactured in the embedding step (S700) is formed using a mechanical polishing method and an electrochemical polishing method, and for example, the surface on which the embedded layer (300) of the ultra-fine electrode (10) manufactured in the embedding step (S700) is formed can be polished by irradiating an ion beam using a FIB device.

[0114]

[0115] <Example 1>

[0116] An insulating member (100) composed of borosilicate glass, having an outer diameter of 1 mm and a capillary shape in which two hollow sections having a diameter of 300 μm are formed and separated from each other along the length direction was prepared.

[0117] Two conductive wires (200) made of stainless steel 304 were prepared, and the two prepared conductive wires (200) were each inserted into two hollow holes formed in the insulating member (100). At this time, the diameter of the prepared conductive wires (200) was 11 μm.

[0118] A semi-finished product (H) was manufactured by heating an insulating member (100) with a conductive wire (200) inserted therein using a laser puller (model name: P-2000, manufacturer: Sutter) and applying tensile force to thin the center of the insulating member (100), and then heating the center of the insulating member (100) and the conductive wire (200) using a laser to cause a break in the center.

[0119] The cross-section of the manufactured semi-finished product (H) was polished using a milling method using FIB.

[0120] The cross-section of the semi-finished product (H) obtained after polishing is immersed in pyrophosphoric acid, which is an etching solution, and the current density calculated according to the reaction area between the etching solution and the cross-section of the semi-finished product (H) is 7.5 mA / cm 2 By applying voltage to the etching solution for 30 minutes, the conductive wire (200) located on the fracture surface of the semi-finished product (H) was etched to form two grooves (G) with a depth of 4 ㎛.

[0121] A plating solution containing copper ions and a plating solution containing nickel ions were prepared.

[0122] In more detail, a first plating solution containing copper ions was prepared by mixing copper sulfate pentahydrate, sulfuric acid, and water so that the concentrations of copper sulfate pentahydrate and sulfuric acid were 249.68 g / L and 98.08 g / L, respectively, and a second plating solution containing nickel ions was prepared by mixing nickel sulfate hexahydrate, nickel chloride hexahydrate, boric acid, and sodium lauryl sulfate so that the concentrations of nickel sulfate hexahydrate, nickel chloride hexahydrate, boric acid, and sodium lauryl sulfate were 341.7 g / L, 47 g / L, 45 g / L, and 0.7 g / L, respectively.

[0123] A semi-finished product (H) with two grooves (G) formed in the first plating solution and an oxidation electrode were immersed together. At this time, an insoluble platinum oxide film electrode was used as the oxidation electrode.

[0124] After immersing the semi-finished product (H) in the first plating solution, an external power source was connected to one of the conductive wires (200) and the oxidation electrode to apply voltage, thereby forming one buried layer (300) in a portion corresponding to the groove (G) formed at the location of one end of the conductive wire (200) to which the voltage was applied.

[0125] A semi-finished product (H) having one buried layer (300) formed was immersed in a second plating solution together with an oxidation electrode. At this time, an insoluble platinum oxide film electrode was used as the oxidation electrode.

[0126] By connecting an external power source to the remaining conductive wire (200) and the oxidation electrode, which have one end surface positioned in a groove (G) where no buried layer (300) is formed, and then applying voltage, one buried layer (300) is formed in a portion corresponding to the groove (G) formed where one end surface of the conductive wire (200) to which voltage is applied is located, thereby manufacturing an ultra-fine electrode (10).

[0127] The surface on which the buried layer (300) of the ultra-fine electrode (10) was formed was polished by irradiating the ion beam using a FIB device.

[0128]

[0129] <Example 1>

[0130] In Test Example 1, to confirm whether the electrode was manufactured smoothly using the manufacturing method according to Example 1, a semi-finished product (H) and an ultra-fine electrode (G) were analyzed using an optical microscope (OM), a scanning electron microscope (SEM), and an energy dispersive spectrometer (EDS).

[0131] Images obtained by OM analysis are shown in Figs. 3 to 7, images obtained by SEM analysis are shown in Figs. 8 to 12, and images obtained by EDS analysis are shown in Figs. 13 to 18.

[0132] FIG. 3 is an image obtained by photographing a semi-finished product (H) manufactured by heating the center of an insulating member (100) into which a conductive wire (200) is inserted in the manufacturing method according to Example 1 so that the center of the insulating member (100) and the conductive wire (200) are fractured, using an OM; FIG. 4 is an image obtained by photographing a semi-finished product (H) whose fracture surface has been polished by a milling method using an FIB, using an OM; FIG. 5 is an image obtained by photographing a conductive wire (200) located on the fracture surface side of the polished semi-finished product (H) after etching it, using an OM; FIG. 6 is an image obtained by photographing an ultra-fine electrode (10) in which a buried layer (300) is formed by filling a groove (G) formed in the semi-finished product (H), using an OM; and FIG. 7 is an image obtained by photographing an ultra-fine electrode (10) in which a buried layer (300) is formed and then polished using an FIB device.

[0133] FIG. 8 is an image obtained by photographing the fracture surface of a semi-finished product (H) manufactured by heating the center of an insulating member (100) into which a conductive wire (200) is inserted in the manufacturing method according to Example 1, thereby causing fracture of the center of the insulating member (100) and the conductive wire (200), using an SEM; FIG. 9 is an image obtained by photographing the fracture surface of a semi-finished product (H) polished through a milling method using an FIB, using an SEM; FIG. 10 is an image obtained by photographing the conductive wire (200) located on the fracture surface side of the polished semi-finished product (H) after forming a groove (G) by etching it, and then photographing it with an SEM; FIG. 11 is an image obtained by photographing the ultra-fine electrode (10) in which a buried layer (300) is formed by filling the groove (G) formed in the semi-finished product (H), using an SEM; FIG. 12 is an image obtained by photographing the ultra-fine electrode (10) in which a buried layer (300) is formed by polishing using an FIB device after the buried layer (300) is formed. This is an image obtained by photographing an ultra-fine electrode (10) with OM.

[0134] FIG. 13 is an image obtained by performing an oxygen analysis using EDS on an ultra-fine electrode (10) in which a buried layer (300) is formed by filling a groove (G) formed in a semi-finished product (H) in a manufacturing method according to Example 1, FIG. 14 is an image obtained by performing an nickel analysis using EDS on an ultra-fine electrode (10) in which a buried layer (300) is formed by filling a groove (G) formed in a semi-finished product (H) in a manufacturing method according to Example 1, and FIG. 15 is an image obtained by performing an copper analysis using EDS on an ultra-fine electrode (10) in which a buried layer (300) is formed by filling a groove (G) formed in a semi-finished product (H) in a manufacturing method according to Example 1.

[0135] FIG. 16 is an image obtained by performing oxygen analysis using EDS on an ultra-fine electrode (10) polished using a FIB device after a buried layer (300) is formed in the manufacturing method according to Example 1, FIG. 17 is an image obtained by performing nickel analysis using EDS on an ultra-fine electrode (10) polished using a FIB device after a buried layer (300) is formed in the manufacturing method according to Example 1, and FIG. 18 is an image obtained by performing copper analysis using EDS on an ultra-fine electrode (10) polished using a FIB device after a buried layer (300) is formed in the manufacturing method according to Example 1.

[0136] Referring to FIGS. 3 to 5 and 8 to 10, it can be confirmed that two grooves (G) are formed when the conductive wire (200) is etched after manufacturing a semi-finished product (H), and referring to FIGS. 6 and 11, it can be confirmed that a buried layer (300) is formed in each portion corresponding to the two formed grooves (G), and referring to FIGS. 7 and 12, it can be confirmed that after the buried layer (300) is formed, the ultra-fine electrode (10) is polished using a FIB device, thereby manufacturing an ultra-fine electrode (10) having a flat single-side surface.

[0137] In addition, referring to FIGS. 13 to 15, it can be confirmed that the buried layers (300) formed in the portions corresponding to the two formed grooves (G) are made of nickel and copper, respectively, and referring to FIGS. 16 to 18, it can be confirmed that after the two buried layers (300) made of nickel and copper, respectively, are formed, the ultra-fine electrode (10) is polished using a FIB device, thereby manufacturing an ultra-fine electrode (10) having a flat single-side surface.

[0138]

[0139] <Example 2>

[0140] In Test Example 2, the hydrogen evolution reaction (HER) that occurs when a negative overvoltage is applied to a 0.5 M sulfuric acid solution using an ultra-fine electrode (10) manufactured by the manufacturing method according to Example 1 was analyzed.

[0141] In more detail, the results obtained when an overvoltage was applied to a buried layer (300) made of copper and formed using the first plating solution among the two buried layers (300) formed on an ultra-fine electrode manufactured by the manufacturing method according to Example 1, when an overvoltage was applied to a buried layer (300) made of nickel and formed using the second plating solution among the two buried layers (300), and when an overvoltage was applied to the two buried layers (300) simultaneously were analyzed.

[0142] The analysis results are shown in Figure 19.

[0143] In FIG. 19, 'Singlepotential Cu' is a result (501) obtained when an overvoltage is applied to a buried layer (300) made of copper and formed using the first plating solution among two buried layers (300), 'Singlepotential Ni' is a result (503) obtained when an overvoltage is applied to a buried layer (300) made of nickel and formed using the second plating solution among two buried layers (300), and 'Bipotential Ni' and 'Bipotential Cu' are results (505, 507) obtained in a buried layer (300) made of nickel and a buried layer (300) made of copper, respectively, when an overvoltage is applied simultaneously to two buried layers (300).

[0144] Referring to FIG. 19, it can be confirmed that when an overvoltage is applied to a buried layer (300) made of copper and formed using the first plating solution among the two buried layers (300), and when an overvoltage is applied to a buried layer (300) made of nickel and formed using the second plating solution among the two buried layers (300), a difference of more than 20 times in hydrogen generation occurs.

[0145] When overvoltage is applied simultaneously to two buried layers (300), it can be confirmed that there is a slight decrease, which is a result confirming that hydrogen ions are consumed simultaneously in both buried layers (300).

[0146] That is, it is possible to arbitrarily replace the metal constituting the buried layer (300) in the ultra-fine electrode (10) with a metal that can be electroplated, and the difference in electrochemical reactions for two buried layers (300) in the ultra-fine electrode (10) in which only the material at a morphologically symmetrical position is changed to nickel, copper, etc. can be compared at once, and errors occurring during repeated measurements can be reduced.

[0147]

[0148] Those skilled in the art will appreciate that the present invention can be implemented in other specific forms without altering its technical spirit or essential characteristics. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims below rather than the detailed description above, and all changes or modifications derived from the claims and their equivalents should be construed as being included within the scope of the present invention.

[0149] The present invention relates to a two-channel ultra-fine electrode for electrochemical analysis, which can be utilized not only as an electrode for a scanning electrochemical microscope but also as a specimen for micro-surface analysis using a scanning electrochemical microscope, and a method for manufacturing the same.

Claims

1. A step of preparing an insulating member in which two cavities are formed along the longitudinal direction; A step of preparing a conductive wire made of a conductive material; A step of inserting the conductive wire into the hollow; A step of manufacturing a semi-finished product by applying heat and an external force to the insulating member into which the conductive wire is inserted to elongate the insulating member and the conductive wire so that the central portion of the insulating member becomes thinner and the central portion of the insulating member and the conductive wire is broken; A step of forming two grooves having a predetermined depth by etching the conductive wire located on the cross-section side of the semi-finished product; and A step of manufacturing an ultra-fine electrode by electroplating the semi-finished product to form a buried layer in a portion corresponding to each of the two grooves; A method for manufacturing a two-channel ultra-fine electrode for electrochemical analysis.

2. In paragraph 1, The steps for manufacturing the above ultra-fine electrodes are Step for preparing the plating solution; A first plating step of immersing the semi-finished product in the plating solution and forming a buried layer in a portion corresponding to one of the two grooves formed in the semi-finished product; and A second plating step comprising: immersing the semi-finished product on which the above-mentioned buried layer has been formed in the plating solution, and forming the buried layer in a portion corresponding to the remaining one of the grooves; A method for manufacturing a two-channel ultra-fine electrode for electrochemical analysis.

3. In paragraph 2, The step of preparing the above plating solution is It is to prepare two plating solutions with different compositions, The above second plating step Immersing the semi-finished product on which the embedded layer is formed in the plating solution having a different composition from the plating solution used in the first plating step to form the embedded layer in a portion corresponding to the remaining one of the grooves. A method for manufacturing a two-channel ultra-fine electrode for electrochemical analysis.

4. In paragraph 2, After the step of manufacturing the above semi-finished product and before the step of forming the groove, further comprising a step of polishing the cross-section of the above semi-finished product; After the above plating step, A step of polishing the surface on which the buried layer of the manufactured ultra-fine electrode is formed; further comprising A method for manufacturing an ultra-fine electrode for electrochemical analysis.

5. In paragraph 4, the step of preparing the plating solution is A step of preparing a plating solution containing ions of a conductive material including at least one of copper, nickel, tin, aluminum, iron, cobalt, zinc, zirconium, chromium, palladium, silver, indium, and lead; A method for manufacturing a two-channel ultra-fine electrode for electrochemical analysis.

6. In paragraph 1, The steps for preparing the above insulating material are Preparing the insulating member comprising at least one of borosilicate glass, silicon oxide, silicon nitride and quartz. A method for manufacturing a two-channel ultra-fine electrode for electrochemical analysis.

7. In paragraph 1, The step of preparing the above conductive wire is Preparing the conductive wire having a diameter less than or equal to the inner diameter of the insulating material exceeding 0 ㎛ A method for manufacturing a two-channel ultra-fine electrode for electrochemical analysis.

8. An insulating member in which two cavities are formed along the longitudinal direction; A conductive wire inserted into the hollow portion so that a groove having a predetermined depth is formed at one end of the insulating member; and A method comprising: forming two buried layers in an area corresponding to the groove formed at one end of the insulating member and comprising a conductive material; A two-channel microelectrode for electrochemical analysis.

Images