KR-102963382-B1 - Methods for repairing superhydrophobic surfaces

Abstract

The present invention relates to a method for repairing a superhydrophobic surface that uses aluminum nitride nanopowder to selectively form micro-nanostructures only on damaged areas, thereby enabling selective restoration of superhydrophobicity only on localized areas where superhydrophobic properties have disappeared, and exhibiting superior adhesion compared to a coating method using resin.

Inventors

• 조한동

Assignees

• 국립목포대학교산학협력단

Dates

Publication Date

20260508

Application Date

20240115

Claims (10)

1. A step of physically removing a region with reduced hydrophobicity from the superhydrophobic surface of the substrate; A step of fixing aluminum nitride nanoparticles to the surface of the physically removed substrate; A step of fixing the aluminum nitride nanoparticles fixed on the surface of the above substrate by applying a water-soluble fixative; A step of forming a nanostructure composed of the nanoparticles on the surface of the substrate, wherein the substrate surface on which the aluminum nitride nanoparticles are fixed is immersed in boiling water to form a hydroxide layer on the surface of the aluminum nitride nanoparticles and cause the nanoparticles to self-bond to each other, thereby forming the nanostructure composed of the nanoparticles on the surface of the substrate. A method for repairing a superhydrophobic surface comprising the step of applying a hydrophobic material to the above nanostructure to achieve superhydrophobicity
2. In Article 1, A method for repairing a superhydrophobic surface characterized by the above-mentioned material being a conductive material.
3. In Article 1, A method for repairing a superhydrophobic surface characterized in that the above-mentioned region with reduced hydrophobicity is a damaged surface structure or coating layer.
4. In Article 1, A method for repairing a superhydrophobic surface characterized by physically removing the area with reduced hydrophobicity by polishing.
5. In Article 1, The step of fixing the aluminum nitride nanoparticles to the surface of the physically removed substrate is, A method for repairing a superhydrophobic surface characterized by immersing it in an aqueous solution containing the above-mentioned aluminum nitride nanoparticles and fixing it by applying an electric field.
6. In Article 1, The step of fixing the aluminum nitride nanoparticles to the surface of the physically removed substrate is, A method for repairing a superhydrophobic surface characterized by applying and fixing a solution containing the above-mentioned aluminum nitride nanoparticles to the surface via a spray.
7. In Article 1, The above nanostructure is, Repair method for a superhydrophobic surface characterized by a flake-shaped nanostructure
8. In Article 1, A method for repairing a superhydrophobic surface characterized in that the above hydroxide layer is an aluminum hydroxide layer.
9. In Article 1, A method for repairing a superhydrophobic surface characterized in that when the substrate surface on which the aluminum nitride nanoparticles are fixed is immersed in boiling water, the water-soluble fixative applied to the aluminum nitride nanoparticles dissolves and is removed.
10. In Article 1, A method for repairing a superhydrophobic surface characterized in that the nanostructure composed of the nanoparticles on the surface of the above substrate is a hierarchical structure of micro-nanometer size.

Description

Methods for repairing superhydrophobic surfaces The present invention relates to a method for repairing a superhydrophobic surface, and more specifically, to a method for repairing a superhydrophobic surface capable of locally repairing a damaged superhydrophobic surface of various conductive substrates. Generally, superhydrophobic surfaces have the characteristic of forming a contact angle of more than 150° when a water droplet touches the surface, causing the water droplet to form like a bead. Substrates exhibiting such superhydrophobic surfaces are useful in various industrial fields requiring self-cleaning functions, antifouling properties, and water resistance. However, the surface structure and coating layer of a superhydrophobic surface can be damaged due to physical impact or chemical damage, and upon such damage, the wetting properties of the superhydrophobic surface deteriorate rapidly in some areas. Most superhydrophobic surfaces are fabricated using physical or chemical methods, but these methods have the disadvantage of being difficult to apply only to localized areas where superhydrophobicity is lost without altering the properties of the undamaged parts. On the other hand, there is a method of mixing nanoparticles into resin and attaching them to the surface; however, this method has the disadvantage that if attached to a superhydrophobic area where the resin is not damaged, it degrades the wetting characteristics of that area and also has low adhesion. FIG. 1 is a flowchart of a method for repairing a superhydrophobic surface according to an embodiment of the present invention. Figure 2 is a diagram illustrating the flowchart of Figure 1. Figure 3 shows electron microscope magnified images of an undamaged area (A1) and a damaged area (A2) of a superhydrophobic surface, as well as images of water droplet contact angles. FIG. 4 shows electron microscope magnified images and water droplet contact angles of each region in a state where a commercial superhydrophobic spray (NeverWet) was applied to each of the undamaged region (A1) and damaged region (A2) of a superhydrophobic surface and repaired using a conventional resin coating method. FIG. 5 shows electron microscope magnified images and water droplet contact angles of each region in a state where repairs were performed in the manner of the present invention on each of the undamaged region (A1) and the damaged region (A2) of the superhydrophobic surface. Figure 6 shows images of the results of an adhesion test using cross-cut tape on a superhydrophobic surface implemented by attaching aluminum nitride nanoparticles as in an embodiment of the present invention, and a superhydrophobic surface produced by applying a commercial superhydrophobic spray as in a conventional method. The terms used in this invention have been selected to be as widely used as possible; however, in specific cases, terms have been arbitrarily selected by the applicant. In such cases, the meaning should be understood by considering the meaning described or used in the detailed description of the invention, rather than merely the name of the term. Hereinafter, the technical configuration of the present invention will be described in detail with reference to preferred embodiments illustrated in the attached drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Throughout the specification, the same reference numerals indicate the same components. FIG. 1 is a flowchart of a method for repairing a superhydrophobic surface according to an embodiment of the present invention, and FIG. 2 is a diagram illustrating the flowchart of FIG. 1. First, referring to FIG. 1, a method for repairing a superhydrophobic surface according to an embodiment of the present invention comprises the steps of: physically removing a region of reduced hydrophobicity from the superhydrophobic surface of a substrate (S100); fixing aluminum nitride nanoparticles to the physically removed substrate surface (S200); fixing the aluminum nitride nanoparticles fixed to the substrate surface by applying a water-soluble fixing agent (S300); immersing the substrate surface with the fixed aluminum nitride nanoparticles in boiling water to form a hydroxide layer on the surface of the aluminum nitride nanoparticles and causing the nanoparticles to self-bond to each other, thereby forming a nanostructure composed of the nanoparticles on the substrate surface (S400); and applying a hydrophobic material to the nanostructure to achieve superhydrophobicity (S500). Referring to FIG. 2, (i) the figure is a schematic representation of the above S100 step, (ii) the figure is a schematic representation of the above S200 step, (iii) the figure is a schematic representation of the above S300 step, (iv) the figure is a schematic representation of the above S400 step, and (v) the figure is a schematic representation of the above S500 step. Here, the substrat