70 results about "Electrochemical etching" patented technology

The invention provides an electrolyte composition, an electrochemical in-situ etching method of non-metallic inclusions for heavy rail steel and application of the electrochemical in-situ etching method. The electrolyte composition comprises the following components in parts by weight: 1.6 to 2.3 parts of lithium chloride, 10 to 13.5 parts of acetylacetone, 45 to 84 parts of methanol and 2 to 43 parts of a reagent A, the reagent A is a mixed aqueous solution of ethylenediamine tetraacetic acid and sodium citrate. The lithium chloride, the acetylacetone, the methanol and the reagent A in specific parts are matched for use, the obtained electrolyte composition is used for in-situ electrochemical etching of the heavy rail steel, and three-dimensional in-situ etching of the non-metallic inclusions in the heavy rail steel can be successfully achieved. The in-situ information of the non-metallic inclusions in the hypereutectoid heavy rail steel is reserved, and the three-dimensional morphology of the non-metallic inclusions can be presented more comprehensively.

The invention relates to the technical field of batteries, in particular to an ultra-thin copper foil, a preparation method thereof and a battery. The preparation method comprises the following steps: providing an initial copper foil, fixing the initial copper foil on an anode plate, placing the initial copper foil and a cathode plate in an electrolyte together, electrifying and carrying out electrochemical etching, so that the thickness of the initial copper foil fixed on the anode plate is reduced, and the ultra-thin copper foil is obtained. According to the method, the thick initial copper foil is used as the anode, the electrochemical etching method is used for preparing the ultra-thin copper foil, the problems that when the ultra-thin copper foil is produced in the prior art, the copper foil with the specific thickness is selected as a carrier, and stripping is needed again, so that the process is tedious, and the cost is high are solved, and a new thought is provided for development of the ultra-thin copper foil. Meanwhile, no specific requirement on the copper foil of the anode exists, that is, the copper foil at the anode is easy to obtain, and the preparation cost of the ultrathin copper foil is effectively reduced.

The invention discloses a preparation method of a metal surface micro-pattern texture, and belongs to the technical field of metal materials and machining thereof. The method comprises the following steps: S1, depositing a metal shading layer on a monocrystalline silicon wafer and patterning, spin-coating a polysiloxane precursor, curing and stripping to prepare a flexible transparent photoetching template; s2, conformally attaching a template to the cleaned bent metal surface, and performing ultraviolet exposure and development to form a cured photoresist mask; and S3, the metal workpiece with the mask serves as an anode, the metal workpiece with the mask is placed in HF-HCl mixed electrolyte for electrochemical etching, the voltage is controlled to be 2.0-5.0 V, the time is 2-8 min, and the micron-sized surface texture of 0.5-2.5 microns is obtained. And the thickness of the template is 0.3-3.0 mm, so that the template can adapt to metal surfaces with different curvature radiuses. According to the method, the photoetching-electrochemical etching process is successfully extended to the curved metal surface for the first time, the pattern fidelity is high, the texture depth is controllable, and the method can be widely applied to key parts, needing mechanical sealing and lubricating, of a carrier vehicle body.

The invention discloses a copper-diamond composite board with high heat conductivity and low expansion coefficient and a preparation method thereof, and belongs to the technical field of preparation of heat-conducting packaging materials for electronic equipment. The preparation method comprises the following steps: grinding and cleaning a base copper plate, milling a rectangular groove to obtain a pretreated base copper plate, and performing electrochemical etching on the pretreated base copper plate to obtain an etched base copper plate; filling a rectangular groove in the etched base copper plate with the carbon nano tube and modified diamond, and compacting for 1-2 minutes under 20-30 MPa to obtain a mixed base copper plate; and the copper covering plate covers one side of the mixed base copper plate filled with the carbon nano tube modified diamond, and then the mixed base copper plate is placed in a graphite mold to be subjected to direct current hot pressing sintering to obtain the copper-diamond composite plate. The prepared copper-diamond composite board has good heat conduction performance and low thermal expansion performance, the bending strength is high, and the problem that the brittleness of the material is too high is effectively solved.

The application provides a preparation method of an aluminum foil current collector, an aluminum foil current collector, a positive pole piece and a lithium ion battery, and relates to the technical field of new materials for energy storage devices. The preparation method of the aluminum foil current collector comprises the following steps: performing pretreatment on the surface of a base material aluminum foil with a purity of 99.7% or above, so that the surface reaches a du Nouy value of 64 dyne / cm or above, to obtain a pretreated base material aluminum foil; performing electrochemical etching treatment on the pretreated base material aluminum foil, to obtain an etched base material aluminum foil; performing cleaning on the etched base material aluminum foil, and then performing post-treatment, so that a phosphating film is formed on the surface, to obtain the aluminum foil current collector. The preparation method of the aluminum foil current collector is an etched aluminum foil current collector for high-safety lithium ion batteries and a preparation method, and can solve the problems that the safety is not good enough when a conventional current collector is used to prepare a lithium ion battery, and the mechanical property of a high-purity aluminum foil is poor after etching.

This invention discloses a peelable nitride structure, its preparation method, and its peeling method. The peelable nitride structure includes a substrate, a buffer layer, a sacrificial layer, an etching layer, and a target nitride structure arranged sequentially. The sacrificial layer has through-cracks. Because a sacrificial layer with through-cracks is introduced into the buffer layer and the target nitride structure, the through-cracks provide flow channels for the solution, allowing for rapid etching of the etching layer via electrochemical etching to achieve peeling of the target nitride structure from the substrate and the buffer layer.

The invention provides a method for applying a low-concentration mixed acid electrolyte to electrochemical etching of a commercial alloy electrode, and belongs to the technical field of electrochemistry. In-situ surface etching is carried out on commercial alloy through mixed acid electrolyte, a surface micro-nano structure is formed, the surface area and the electrochemical active area of the commercial alloy are remarkably increased, and the method comprises the following steps that firstly, phosphoric acid, hydrochloric acid, sulfuric acid or nitric acid are mixed according to a specific combination and proportion, and a low-concentration mixed acid solution is obtained; and 2, using a double-cathode strategy in an electrolytic bath, fixing the pretreated commercial alloy in the electrolytic bath as an anode and electrodes on two sides as cathodes, adding the mixed acid electrolyte in the step 1 for electrochemical etching, taking out after the reaction is completed, cleaning, and carrying out vacuum drying. According to the method, the surface area and the electrochemical active area of the commercial alloy can be remarkably increased, a specific surface micro-nano structure is formed according to different commercial alloy types and etching parameters, and the method is suitable for hydrogen production application of alkaline electrolyzed water and electrolyzed seawater.

The application discloses a foil type tantalum electrolytic capacitor anode with super high capacitance density and a preparation method thereof. The energy source is a pulse direct current power supply, the pre-processed tantalum foil is used as the anode, the graphite electrode or inert metal is used as the cathode, the anode and the cathode are connected with the pulse direct current power supply, and are placed in an etching solution to perform electrochemical etching. The etching foil is subjected to anodic oxidation in a phosphoric acid aqueous solution to obtain the etched tantalum foil. The electrochemical etching process truly realizes the preparation of the high specific capacity etched tantalum anode foil. For the anode foil with a voltage resistance of 8.3V, the specific capacity is up to 570nF / mm 2 , and the thickness is less than 30μm, which is only 1 / 10 of the traditional sintered tantalum capacitor. If the tantalum capacitor is packaged in a sheet type, the size can be even reduced to below 100μm, which can almost meet the requirements of the most stringent embedded capacitor in technology. If the tantalum capacitor is packaged in a winding type, the maximum capacity can fully meet the requirements of more than 90% of the power system.

The invention discloses a copper-zinc catalyst material for carbon dioxide reduction and a preparation method thereof. The method comprises the following steps: by taking a zinc acetate solution as an electrolyte, carrying out constant-potential electrochemical deposition on foamy copper to obtain a copper-zinc base mold; cO2 is introduced into a cathode chamber of an electrolytic tank with a KHCO3 solution as an electrolyte and a copper-zinc-based mold as a working electrode until the cathode chamber is in a saturated state, and the copper-zinc-based mold is subjected to electrochemical etching through linear voltammetry scanning to obtain the copper-zinc catalyst. The method is simple and controllable, and the obtained catalyst has high specific surface area and excellent carbon dioxide reduction catalytic activity.

A method for producing a planar semiconductor surface includes forming a workpiece that has a carrier substrate, one or more insulating layers, a semiconductor layer, a first etch stop layer, and a second etch stop layer; forming a contact on the workpiece; biasing the workpiece to a second voltage through the contact; etching the second etch stop layer and part of the first etch stop layer with a photo-electrochemical etching and the second voltage that selectively removes the second etch stop layer faster than the first etch stop layer; biasing the workpiece to a first voltage through the contact; and etching the first etch stop layer and part of the semiconductor layer with the photo-electrochemical etching and the first voltage that selectively removes the first etch stop layer faster than the semiconductor layer to produce a semiconductor device with a planar surface on the semiconductor layer.

The invention relates to the technical field of capacitors, and discloses an aluminum foil for an electrolytic capacitor and a production method thereof, and the production method comprises the steps: preparing a photochemical reaction main solution containing bis (2-ethylhexyl) phosphate, terephthalic acid, a photosensitive catalytic etching system and sulfolane; immersing a high-purity aluminum foil substrate into the reaction main liquid, performing patterning ultraviolet irradiation on the surface of the high-purity aluminum foil substrate, and generating an organic-inorganic hybrid dielectric layer in situ in an irradiated preset patterning area; and finally carrying out thermocuring treatment. The surface of the aluminum foil prepared by the invention comprises the patterned area formed by the dielectric layer and the non-patterned area for keeping the conductive characteristic of the metal. According to the method, a traditional electrochemical corrosion and formation two-step method is integrated into a one-step photochemical method, the technological process is remarkably simplified, and accurate construction of the functional area on the single aluminum foil is achieved. Meanwhile, the method is carried out in a non-water system, so that the generation of chlorine-containing wastewater is fundamentally avoided, and the environmental load is reduced.

This invention discloses a wettable hybrid surface directional transport fog collection device and method. The device includes: an aluminum alloy substrate and a honeycomb and cactus spine coupled biomimetic surface on the aluminum alloy substrate; the honeycomb and cactus spine coupled biomimetic surface is composed of superhydrophobic and superhydrophilic regions; the superhydrophobic region is the aluminum alloy substrate surface after electrochemical etching and fluorosilane modification treatment; the superhydrophilic region is a honeycomb and cactus spine coupled biomimetic pattern formed by laser precision etching on the superhydrophobic region, and the fluorosilane layer in this pattern region is removed and the surface microstructure is reconstructed. Specifically, the pattern consists of multiple wedge-shaped channels of the same size arranged periodically, in a regular arrangement simulating a honeycomb; the wedge-shaped channels have a width gradient from the narrow end to the wide end along the length direction. This invention can achieve full-process optimization from efficient fog droplet capture, rapid condensation, to directional transport and inertial desorption in a two-dimensional plane.

This application provides an electrochemical etching method for a metal composite, comprising a first metal part and a second metal part interconnected. The electrochemical etching method includes: anodizing the metal composite to form a first oxide film on the surface of the first metal part and a second oxide film on the surface of the second metal part; placing the anodized metal composite in a sealing solution to seal the first oxide film; placing the metal composite with the first oxide film sealed in an etching solution and applying ultrasonic waves, using the metal composite as the anode, to perform electrochemical etching to remove the second oxide film and form micropores on the surface of the second metal part; wherein the etching solution comprises: water, a water-miscible organic solvent, an acid, and a soluble chloride. The method provided in this application solves the problems of complex pretreatment, difficulty in corrosion, and difficulty in protecting aluminum alloys in micropore etching of metal composites.

The application discloses a preparation method of a steel skeleton plastic composite pipe and the steel skeleton plastic composite pipe and belongs to the technical field of pipes. The method is characterized in that: low-carbon steel wires are subjected to electrochemical etching to form a nano-scale porous structure, and are woven into a gradient porosity steel wire mesh with porosity gradually decreasing in the thickness direction of the pipe wall; the steel wire mesh is subjected to immersion in a molten mixed liquid containing maleic anhydride grafted high-density polyethylene and an initiator under ultrasonic vibration, so as to form a chemical bonding interface layer on the surface of the steel wire; and the steel wire mesh is sent into a co-extrusion die to fill high-density polyethylene melt under high pressure and is once composite formed to obtain a pipe blank, and the pipe blank is subjected to step temperature control cooling and heat treatment to obtain a finished product. The steel wire surface of the composite pipe is connected with the plastic matrix through a covalent chemical bond, and the steel wire end face at the pipe end is completely closed by the continuous plastic matrix. The application realizes synergistic effects in the aspects of interface bonding strength, corrosion resistance and thermal cycle stability.

The invention belongs to the technical field of detection, and particularly relates to an in-situ electrochemical etching silk-screen printing silver electrode, a preparation method thereof and an EC-SERS platform. On the basis of a pesticide protonation-EC-SERS combined strategy, an independently prepared SPE-Ag electrode is used as an enhanced substrate, a mobile phone is coupled to regulate and control a portable electrochemical workstation to apply potential, an EC-SERS rapid detection platform is established, the EC-SERS rapid detection platform is successfully used for rapid and sensitive detection of the residues of the neonicotinoid pesticide imidacloprid, the detection limit is as low as 1.5 nM, and the EC-SERS rapid detection platform can be used for rapid and sensitive detection of the residues of the neonicotinoid pesticide imidacloprid. According to the present invention, the problem that the on-site real-time application of the EC-SERS technology is limited by the equipment size, the cost and the operation complexity is solved, the portable and low-threshold on-site detection platform is provided, the detection cost is significantly reduced while the sensitivity of the traditional EC-SERS is maintained by the platform, the operation threshold is substantially reduced, and the detection efficiency is improved. And a method with a better application prospect is hopefully provided for on-site real-time detection of pesticide residues.

This invention relates to a method for preparing an electrocatalytic electrode for degrading antibiotics and its application. The method is characterized by the following steps: S1: electrochemical etching; S2: KOH etching; S3: carbon nanofiber growth. In this invention, pores are created on the surface of a graphite sheet by etching, and then carbon nanofibers are grown on the surface of the graphite sheet using chemical vapor deposition to obtain a composite electrode composed of graphite and carbon nanofibers. Experimental results show that the composite electrode, as an anode, can achieve highly efficient electrocatalytic degradation of various antibiotics.

The invention provides a tungsten needle electrochemical corrosion microchannel control method and system, and relates to the technical field of micromachining and electrochemical corrosion precision control, and the method comprises the following steps: obtaining corrosion state characteristic data and a boundary characteristic image of a microchannel in a tungsten needle electrochemical corrosion process; based on the boundary feature image of the microchannel, generating structural integrity data; fusing the corrosion state characteristic data and the structural integrity data to form comprehensive state data, and performing time sequence correlation analysis on the comprehensive state data to predict a depth change sequence of the micro-channel; and based on the depth change sequence of the microchannel, a corrosion parameter matching degree is calculated by combining a deep learning controller, corrosion control parameters for optimizing the morphology of the microchannel are generated based on the corrosion parameter matching degree, and the corrosion process of the microchannel is controlled through the corrosion control parameters. According to the method, the morphology control precision and the process stability of micro-channel preparation are improved.

The application discloses a porous aluminum current collector and a preparation method thereof, a negative plate and a sodium battery, and relates to the technical field of sodium ion batteries. The application is characterized in that the aluminum base material is subjected to surface modification, a porous material is prepared through electrochemical etching, sodium-active ions are introduced, a three-dimensional porous structure with high surface energy is prepared, and finally, a thin active material coating (carbon layer) with ion and electron conductivity is coated, so that the negative electrode dosage is reduced, the cost is reduced, the energy density is improved, the fatal defects such as dendrites and unstable interface of the negative electrode-free system are avoided, and the balance between performance and safety is achieved.

The utility model relates to a tungsten needle etcher based on electrochemical oxidation under microscope, including alternating -current power supply system, electrochemical etching liquid lifting system, microscope system, tungsten wire electrode clamping system, illumination system five part compositions. The tungsten needle etcher of the utility model, its structure is reasonable, and convenient operation can directly watch the corrosion degree of the needle tip of tungsten needle under microscope, avoids the operation of installing tungsten needle back and forth many times, and the accuracy increases, greatly shortens the time of making tungsten needle.

A method to lift-off and remove thin-film III-nitride layers from a growth substrate. The method comprises epitaxially growing III-nitride layers including a sacrificial layer on or above a substrate, wherein the sacrificial layer has an electron carrier concentration from 1 x 1019 cm-3 to 1 x 1021 cm-3; exposing at least a portion of the sacrificial layer to an electrolyte in an electrochemical etching apparatus; at least partially etching the exposed portion of the sacrificial layer in the electrochemical etching apparatus to expose at least an area of a newly-created surface of the III-nitride layers; and removing the III-nitride layers from the etched sacrificial layer.

The invention provides a tungsten filament electrolyte for preparing a photovoltaic screen printing plate through electrochemical etching, and the etching speed is controlled by controlling the current of the electrolyte, so that the tungsten filament screen printing plate with smooth tungsten filament surface, small wire diameter and long service life is obtained. The method is characterized in that the method is an acidic solution, the acidic solution is obtained by mixing concentrated sulfuric acid and methanol, and the volume ratio of the concentrated sulfuric acid to the methanol is 1: (6.2-7.8).

A medical product and a method of surface treatment and / or manufacture of a medical product. The medical product includes a metal or an alloy or consists of a metal or an alloy. The method includes the following steps: a) dulling a surface of the medical product, b) electropolishing the dulled surface of the medical product, c) electrochemically etching the dulled and electropolished surface of the medical product and d) electropolishing the dulled, electropolished and electrochemically etched surface of the medical product. The medical product has at least one of the following features:a pitting corrosion potential of 100 mV to 1200 mV, and / ora contact angle of 80° to 140°, and / ora passive layer having a thickness of 1 nm to 10 nm, which coats at least sections of the surface of the medical product.

The invention belongs to the field of alcohol catalytic oxidation, and particularly relates to a multi-component alloy alcohol oxidation electrode, preparation and application of the multi-component alloy alcohol oxidation electrode in an alcohol fuel cell, and the preparation method of the electrode comprises the following steps: depositing an M1-M2-M3-LDH material on a carbon-based carrier, and then performing reduction treatment to prepare an M1-M2-M3-multi-component alloy carbon-based carrier; and preparing a precursor electrode by taking the M1-M2-M3-multicomponent alloy and carbon-based carrier as an active material, and carrying out CV electrochemical etching in an acidic electrolyte by taking the precursor electrode as a working electrode to prepare the multicomponent alloy alcohol oxidation electrode, wherein M1 comprises at least one noble metal of Pt, Au, Ag, Pd and Ir; m2 comprises at least one divalent metal of Co, Ni, Cu, Zn and Mn; m3 comprises at least one trivalent metal of Ga, In, Bi, Sb and Fe; the molar weight ratio of M1 to M2 to M3 is 1: (1-8): (1-6); the number of CV circulation circles of the CV electrochemical etching is 10 to 100. The material provided by the invention can effectively resist the problem of CO poisoning, and can significantly improve the alcohol catalytic oxidation effect.

The present application relates to a kind of flip GaN HEMT device array transfer and heterogeneous integration method and its device array, which is by setting up GaN HEMT device array structure containing heavily doped GaN sacrificial layer and high resistance layer of blocking leakage current path, covering passivation insulating layer on the surface of device to protect device, by opening via hole on passivation insulating layer to expose source drain and gate and then bond it to target substrate by bonding metal, further combined with specific electrochemical etching method, release HEMT array from rigid substrate, realize the lossless peeling of device array, release the stress inside material, effectively solve the problem of buffer layer and substrate leakage, greatly improve the performance of HEMT device, provide new channel for the heterogeneous integration of HEMT device and target substrate, greatly widen the use range of electronic power device.

This invention discloses a catalyst for topological interface engineering-controlled lattice oxygen, its preparation method, and its application, belonging to the field of catalyst technology. The invention prepares a catalyst via a two-step method of electrochemical etching and thermal oxidation. The catalyst has an IrGa intermetallic compound core, a Ga-vacancy-rich transition layer in the middle, and a crystalline IrO2 layer as the outer shell. This invention modulates the local electronic structure of the catalyst through the interface topological confinement effect, breaking the trade-off bottleneck between high activity and structural instability under the LOM mechanism in acidic OER. By suppressing the accumulation and dissolution of deep lattice defects, a reversible lattice oxygen redox process is achieved, thereby improving the catalyst's lifetime, activity, and stability.

The application discloses a method for preparing medium-high-entropy two-dimensional carbide nanomaterials from waste denitration catalysts. The method comprises the following steps: powdering the waste denitration catalysts; mixing the waste denitration catalyst powder, aluminum oxide powder and graphite powder according to a set molar ratio, adding a PVB binder in the mixing process, and then pressing into a porous block; taking the porous block as a first cathode, taking a graphite electrode as a first anode, and combining with a molten salt electrolyte to form a first electrolysis system; introducing argon as a protective atmosphere into the first electrolysis system, setting the electrolysis temperature and electrolysis voltage of the first electrolysis system to perform electrolysis, and generating a medium-high-entropy MAX ceramic phase in the first cathode through reduction; taking the first cathode generating the medium-high-entropy MAX ceramic phase as a second anode, taking the first anode as a second cathode, combining with a molten salt electrolyte to form a second electrolysis system, setting the electrolysis temperature and electrolysis voltage of the second electrolysis system to perform electrolysis, and performing electrochemical etching on the medium-high-entropy MAX ceramic phase to obtain medium-high-entropy two-dimensional carbide nanomaterials.

This invention provides an aluminum capacitor shell and a capacitor containing the same, relating to the field of capacitor technology. It solves the technical problem of short circuits caused by the easy contact of the anode foil with the bottom of the aluminum shell due to capacitor size reduction. The capacitor shell includes a shell body molded from an aluminum sheet, with an insulating film coated on the inner bottom wall of the shell body. The inner wall of the shell body has a rough, uneven surface, formed by electrochemical etching with micro-etched pits. The insulating film coating on the bottom of the aluminum shell prevents short circuits caused by the anode foil contacting the bottom of the shell. The micro-etched pits on the inner wall of the aluminum shell increase the contact area between the shell wall and the rubber stopper at the waist, confining the electrolyte within the shell. The etched pits on the inner wall of the aluminum shell achieve surface roughening, increasing the shell wall roughness, enhancing contact with the rubber stopper, and improving sealing performance.

The application relates to an electrochemical etching method of a porous electrode and an electrolytic water electrode. The electrochemical etching method comprises the following steps: using a nickel-iron metal salt containing a pore-forming agent as an electroplating solution, using a nickel mesh as a working electrode and a platinum sheet as a counter electrode, performing constant-current electrodeposition in the electroplating solution, ensuring that the deposition rate remains unchanged, obtaining a nickel mesh material loaded with a porous nickel-iron alloy deposition layer; cleaning and drying; using a high-temperature furnace to perform fast firing treatment to improve the stability of the catalyst layer; in a two-electrode system, using prepared hydrochloric acid as an etching solution, using the obtained electrode as a working electrode and a platinum sheet as a counter electrode, performing constant-current etching, ensuring that the etching rate remains unchanged, and obtaining a porous electrode finished product after etching. Compared with the prior art, the application solves the problems of insufficient catalytic area of a traditional porous electrode and poor bubble release structure on the surface; is suitable for industrial large-scale production, has a simple preparation process, good repeat stability and low cost.

The invention discloses a method for improving the water electrolysis oxygen evolution reaction performance of a Mn-based high-entropy alloy catalyst through electrochemical etching, and belongs to the field of electrochemistry. The preparation method comprises the following steps: putting a substrate into a uniformly mixed salt solution containing five metals of Fe, Co, Ni, Mn and Mo, carrying out hydrothermal reaction to obtain a high-entropy alloy precursor, and calcining to obtain a high-entropy alloy; and then the high-entropy alloy is placed in a (NH4) 2SO4 solution, electrochemical etching treatment is carried out, and therefore the oxygen evolution reaction performance of the Mn-based high-entropy alloy catalyst is improved. The method is simple and obvious in effect, the Mn-based high-entropy alloy material with the good microstructure can be obtained, the specific surface area of the catalyst is remarkably increased, and the water electrolysis oxygen evolution reaction performance of the Mn-based high-entropy alloy material is improved.

The invention discloses a preparation method of a silicon carbide ceramic membrane, and belongs to the technical field of ceramic membrane preparation. The method comprises the following steps: firstly, loading organic sol on the surface of a porous silicon carbide support body, and constructing a nano-porous carbon prefabricated layer through gelation and carbonization treatment; then introducing a silicon source, heating in a vacuum or inert atmosphere for reactive sintering, infiltrating liquid silicon into the carbon skeleton to generate silicon carbide in situ, and filling pores with excessive silicon to form a compact silicon carbide / silicon composite layer; and finally, removing a silicon phase in the composite layer through selective chemical or electrochemical etching to obtain the nano-aperture silicon carbide ceramic membrane. According to the invention, the problems of high sintering temperature, difficult pore size control and easy cracking in the traditional silicon carbide film preparation are solved by utilizing a sacrifice template strategy. The prepared membrane layer has the characteristics of narrow pore size distribution, large permeation flux, good chemical stability and the like, and is suitable for precise filtration and separation.