Preparation method of reduced graphene oxide packaged metal grid transparent conductive film

Abstract

The invention discloses a preparation method of a reduced graphene oxide packaged metal grid transparent conductive film. The preparation method comprises the following steps: S1, preparing a metal grid; s2, preparation of a packaging material: doping the graphene oxide aqueous dispersion liquid with isopropanol to obtain the packaging material; s3, spin coating of a packaging layer: spin coating the packaging material on the metal grid to obtain a graphene oxide coating layer, namely the packaging layer; s4, performing atmospheric plasma reduction treatment: setting parameters of an atmospheric plasma processor, and performing scanning reduction treatment on the packaging layer through a nozzle of the atmospheric plasma processor; and S5, obtaining a reduced graphene oxide packaging layer, namely the composite transparent conductive film. Compared with the prior art, the transparent conductive film (namely the reduced graphene oxide packaging layer) prepared by the method can enhance the conductivity of the packaging layer and improve the overall photoelectric property of the film.

Description

Technical Field

[0001] The invention belongs to the technical field of thin-film optoelectronic components, and in particular relates to a method for preparing a reduced graphene oxide encapsulated metal grid transparent conductive film. Background Art

[0002] With the widespread application of thin-film optoelectronic components, such as flexible wearable electronics, solar thin-film batteries, smart windows, etc., flexible transparent conductive films are important components of optoelectronic devices, and the requirements for optoelectronic performance are getting higher and higher. The traditional transparent conductive material is In2O3 (ITO), which has excellent optoelectronic performance, but with the rapid development of the economy, due to the large brittleness of indium elements, shortage of reserves, and poor environmental affinity. Researchers are studying a new generation of transparent conductive materials to replace traditional ITO. As a new generation of flexible transparent electrode materials, the metal grid, the grid lines form a connected conductive path, and the pattern gaps inside the grid play a role in light transmission. The metal grid can adjust the spacing, line width, pattern shape and other parameters of the metal grid according to the application requirements to adjust the optoelectronic performance of the optoelectronic device and adapt to the application requirements. Although it has excellent optoelectronic adjustable performance, the metal grid transparent conductive film exposed to humid air is prone to corrosion due to its large specific surface area. Therefore, the process of encapsulating the metal grid transparent conductive film is of great significance for prolonging the service life of the device.

[0003] In the prior art, the encapsulation of the metal mesh transparent conductive film is mostly based on the metal mesh and other materials, and the coating method is drip coating, scraping, spraying, spin coating, etc. The selection of packaging materials is divided into conductive materials (conductive polymers, graphene, carbon nanotubes, MXene, etc.) and non-conductive materials (such as graphene oxide, biomass materials, UV glue, etc.) according to whether they are conductive. When conductive materials are used as packaging coatings, acid and alkali corrosion of the metal mesh may be introduced (such as the conductive polymer PEDOT:PSS dispersion is strongly acidic), or the dispersion is non-uniform, causing discontinuity of the packaging layer (such as agglomeration in graphene and carbon nanotube dispersions). For non-conductive materials, the coating layer has good continuity, but as the thickness of the coating packaging layer increases, the photoelectric performance of the metal mesh transparent conductive film gradually deteriorates.

[0004] Therefore, in view of the above technical problems, it is necessary to provide a method for preparing a reduced graphene oxide encapsulated metal grid transparent conductive film.

[0005] The information disclosed in this background technology section is only intended to enhance the understanding of the overall background of the invention and should not be regarded as an acknowledgment or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art. Summary of the invention

[0006] The object of the present invention is to provide a method for preparing a reduced graphene oxide encapsulated metal grid transparent conductive film, which can enhance the conductivity of the encapsulation layer and improve the overall photoelectric performance of the film.

[0007] In order to achieve the above object, a technical solution provided by a specific embodiment of the present invention is as follows:

[0008] The method for preparing a metal grid transparent conductive film encapsulated by reduced graphene oxide comprises the following steps:

[0009] S1, metal grid preparation;

[0010] S2. Preparation of packaging material: doping the graphene oxide aqueous dispersion with isopropanol to obtain a packaging dispersant, i.e., a packaging material;

[0011] S3, spin coating the encapsulation layer: spin coating the encapsulation material on the metal grid to obtain a graphene oxide coating layer, i.e., an encapsulation layer;

[0012] S4, atmospheric plasma reduction treatment: setting the parameters of the atmospheric plasma treatment machine, and performing scanning reduction treatment on the encapsulation layer through the atmospheric plasma treatment machine nozzle;

[0013] S5. Obtaining a reduced graphene oxide encapsulation layer, i.e., a composite transparent conductive film.

[0014] In one or more embodiments of the present invention, in S2, the volume ratio of the graphene oxide aqueous dispersion to isopropanol is 1:1.

[0015] In one or more embodiments of the present invention, in S3, the packaging material is spin-coated 2-5 times.

[0016] In one or more embodiments of the present invention, in S3, the spin coating rate is 2000rpm-4000rpm.

[0017] In one or more embodiments of the present invention, in S4, setting the parameters of the atmospheric plasma processor includes setting the power of the atmospheric plasma processor to 300-400W.

[0018] In one or more embodiments of the present invention, in S4, setting the atmospheric plasma processor parameters further includes setting the distance between the atmospheric plasma processor nozzle and the packaging layer to 2-3 cm.

[0019] In one or more embodiments of the present invention, in S4, the scanning and restoring process adopts an intermittent scanning method.

[0020] In one or more embodiments of the present invention, the specific steps of the intermittent scanning are: the atmospheric plasma treatment machine nozzle moves left and right and up and down in sequence, scanning for 1 minute and cooling for 1 minute.

[0021] In one or more embodiments of the present invention, the scanning and restoring processing time is 8-12 minutes.

[0022] In one or more embodiments of the present invention, in S1, the metal grid preparation step includes chemical plating and laser direct writing.

[0023] Compared with the prior art, the present invention adopts a spin coating process, and the uniformity of the coating layer is significantly increased compared with coating methods such as scraping, dripping, and spraying. By setting the optimal number of spin coating times and spin coating rate, the encapsulation layer can ensure effective encapsulation of the metal grid;

[0024] The present invention adopts atmospheric plasma to reduce the graphene oxide coating layer, taking into account the advantages of graphene oxide dispersibility and reduced graphene oxide conductivity, so that the graphene oxide encapsulation layer is in situ reduced to reduced graphene oxide, which can enhance the conductivity of the composite film;

[0025] The present invention adopts intermittent plasma treatment, which reduces the heat accumulation of high-energy atmospheric plasma on the surface of the metal grid transparent conductive film and effectively protects the continuity of the metal grid and the polymer substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1 The present invention is a flowchart of a method for preparing a metal grid transparent conductive film encapsulated by reduced graphene oxide in one embodiment of the present invention. DETAILED DESCRIPTION

[0028] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0029] like Figure 1As shown, a method for preparing a reduced graphene oxide encapsulated metal grid transparent conductive film in one embodiment of the present invention comprises the following steps:

[0030] S1. Metal grid preparation: The metal grid is prepared by chemical plating and laser direct writing;

[0031] S2. Preparation of packaging material: doping the graphene oxide aqueous dispersion with isopropanol to obtain a packaging dispersant, i.e., a packaging material;

[0032] S3, spin coating the encapsulation layer: spin coating the encapsulation material on the metal grid to obtain a graphene oxide coating layer, i.e., the encapsulation layer;

[0033] S4, atmospheric plasma reduction treatment: setting the parameters of the atmospheric plasma treatment machine, and performing scanning reduction treatment on the encapsulation layer through the atmospheric plasma treatment machine nozzle;

[0034] S5. Obtaining a reduced graphene oxide encapsulation layer, i.e., a composite transparent conductive film.

[0035] The transparent conductive film (i.e., reduced graphene oxide encapsulation layer) prepared by this method can enhance the conductivity of the encapsulation layer and improve the overall photoelectric performance of the film. This method uses a spin coating method of graphene oxide to coat the encapsulation layer, and the coating process ensures the uniformity of the coating layer. Compared with directly spin coating the graphene dispersion, the graphene oxide dispersion has better continuity and does not have a segregation phenomenon, which will improve the uniformity of the encapsulation layer and reduce the scattering of incident light.

[0036] Further atmospheric plasma reduction treatment can promote the transformation of graphene oxide to the conjugated structure of graphene, restore its conductivity, and enhance the conductivity of the film. Atmospheric plasma reduction has high efficiency and simple process. Compared with chemical reduction of graphene oxide, it can effectively prevent the metal grid from contacting the reducing agent solution and causing corrosion. Compared with the thermal reduction process of graphene oxide, it can not damage the substrate material. Therefore, atmospheric plasma reduction of graphene oxide film is used to encapsulate metal grids, improve the chemical stability of metals, and increase the conductivity of composite films, which is of great significance.

[0037] Preferably, in S2, the volume ratio of the graphene oxide aqueous dispersion to the isopropanol doping is 1:1 to improve coating wettability.

[0038] Too few coating times and too high a spin coating rate will result in incomplete encapsulation; too many spin coating times and too low a spin coating rate will result in too thick an encapsulation layer, significantly reducing the photoelectric performance of the composite film. Therefore, in S3, the number of spin coating times of the encapsulation material is preferably 3 times to ensure that the encapsulation layer can completely cover the surface of the metal grid; the spin coating rate is preferably 3000 rpm for better results, which can ensure that the metal grid is completely covered as much as possible while the thickness of the encapsulation layer is relatively thin.

[0039] Since the distance between the atmospheric plasma treatment machine nozzle and the packaging layer is too close, it is easy to cause local overheating of the metal grid and thermal damage to the polymer transparent substrate, and the reduction effect of the graphene oxide coating layer is poor if the distance is too far. Therefore, in S4, the power of the atmospheric plasma treatment machine is set to 350W and the distance between the atmospheric plasma treatment machine nozzle and the packaging layer is set to 2-3cm.

[0040] In order to prevent the accumulation of heat effects caused by the atmospheric plasma treatment process from causing damage to the metal grid and the polymer substrate, in S4, the scanning reduction treatment adopts an intermittent scanning method.

[0041] The specific steps of intermittent scanning are as follows: the nozzle of the atmospheric plasma treatment machine moves rapidly left, right, up and down in sequence, scanning for 1 minute and cooling for 1 minute.

[0042] Preferably, the scanning reduction treatment time (excluding cooling time) is more suitable for 8-12 minutes, and 10 minutes has the best effect.

[0043] Compared with the prior art, the present invention adopts a spin coating process, and the uniformity of the coating layer is significantly increased compared with coating methods such as scraping, dripping, and spraying. By setting the optimal number of spin coating times and spin coating rate, the encapsulation layer can ensure effective encapsulation of the metal grid;

[0044] The present invention adopts atmospheric plasma to reduce the graphene oxide coating layer, taking into account the advantages of graphene oxide dispersibility and reduced graphene oxide conductivity, so that the graphene oxide encapsulation layer is in situ reduced to reduced graphene oxide, which can enhance the conductivity of the composite film;

[0045] The present invention adopts intermittent plasma treatment, which reduces the heat accumulation of high-energy atmospheric plasma on the surface of the metal grid transparent conductive film and effectively protects the continuity of the metal grid and the polymer substrate.

[0046] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0047] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A method for preparing a metal grid transparent conductive film encapsulated by reduced graphene oxide, characterized in that: The following steps are involved: S1, metal grid preparation; S2. Preparation of packaging material: doping the graphene oxide aqueous dispersion with isopropanol to obtain a packaging dispersant, i.e., a packaging material; S3, spin coating the encapsulation layer: spin coating the encapsulation material on the metal grid to obtain a graphene oxide coating layer, i.e., an encapsulation layer; S4, atmospheric plasma reduction treatment: setting the parameters of the atmospheric plasma treatment machine, and performing scanning reduction treatment on the encapsulation layer through the atmospheric plasma treatment machine nozzle; S5. Obtaining a reduced graphene oxide encapsulation layer, i.e., a composite transparent conductive film.

2. The method for preparing a reduced graphene oxide encapsulated metal grid transparent conductive film according to claim 1, characterized in that: In S2, the volume ratio of the graphene oxide aqueous dispersion to isopropanol is 1:

1.

3. The method for preparing a reduced graphene oxide encapsulated metal grid transparent conductive film according to claim 1, characterized in that: In S3, the packaging material is spin-coated 2-5 times.

4. The method for preparing the reduced graphene oxide encapsulated metal grid transparent conductive film according to claim 3, characterized in that: In S3, the spin coating rate is 2000rpm-4000rpm.

5. The method for preparing a reduced graphene oxide encapsulated metal grid transparent conductive film according to claim 1, characterized in that: In S4, setting the parameters of the atmospheric plasma processing machine includes setting the power of the atmospheric plasma processing machine to 300-400W.

6. The method for preparing the reduced graphene oxide encapsulated metal grid transparent conductive film according to claim 5, characterized in that: In S4, setting the parameters of the atmospheric plasma processing machine also includes setting the distance between the atmospheric plasma processing machine nozzle and the packaging layer to 2-3 cm.

7. The method for preparing a reduced graphene oxide encapsulated metal grid transparent conductive film according to claim 1, characterized in that: In S4, the scanning and restoring process adopts an intermittent scanning method.

8. The method for preparing a reduced graphene oxide encapsulated metal grid transparent conductive film according to claim 7, characterized in that: The specific steps of the intermittent scanning are: the nozzle of the atmospheric plasma treatment machine moves left and right and up and down in sequence, scanning for 1 minute and cooling for 1 minute.

9. The method for preparing the reduced graphene oxide encapsulated metal grid transparent conductive film according to claim 7 or 8, characterized in that: The scanning and restoring process takes 8-12 minutes.

10. The method for preparing a reduced graphene oxide encapsulated metal grid transparent conductive film according to claim 1, characterized in that: In S1, the metal grid preparation step includes chemical plating and laser direct writing.

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