WO2019136624A1 - Method for scalable preparation of flexible transparent electrode - Google Patents

Abstract

A method for scalable preparation of a flexible transparent electrode is characterized by the following steps: 1. substrate pretreating; taking out a cleaned substrate, drying with high purity nitrogen, and placing the substrate in an ultraviolet ozone treatment for treatment; 2. preparation of a conductive solution based on a doped PEDOT:PSS dispersion liquid; mixing a PEDOT:PSS dispersion liquid and an acid solution in a container to obtain a conductive solution containing the doped PEDOT:PSS dispersion liquid; the concentration of the acid in the conductive solution containing the doped PEDOT:PSS dispersion liquid ranging from 0.01-0.9 mol/L; the concentration of the acid solution ranging from 0.8-2 mol/L; 3. spin coating the dispersion liquid; depositing the conductive solution obtained in step 2 on the substrate obtained in step 1 by a spin coating process; 5. heat treatment of a transparent electrode; heating the substrate covered with the conductive solution prepared in step 3. at a constant temperature, cooling naturally to room temperature to obtain a transparent electrode. The constant temperature is in a range of 100-170 °C, and the heating time is 5-120 mins.

Description

Method for preparing flexible transparent electrode on a large scale Technical field

The invention relates to the field of organic optoelectronic technology materials, in particular to a method for preparing flexible transparent electrodes on a large scale.

Background technique

Transparent conductive electrodes are an important component of various electronic devices, including touch screens, displays, thin film solar cells, and the like. Currently, transparent conductive electrodes generally employ a metal oxide such as an indium tin oxide (ITO) film. Due to the limited reserves of indium metal elements, metal oxide films require vacuum coating equipment and technology, and various factors lead to an increase in the cost of the electrode; more importantly, due to the intrinsic brittleness of metal oxides, it cannot be applied to the current rise. In a flexible device.

The study found that transparent electrodes prepared based on poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonic acid) (PEDOT:PSS) have higher light transmittance and performance in terms of flexibility. Can also meet people's requirements.

However, the electrode of PEDOT:PSS has a large square resistance, which makes the conductivity lower than 1S/cm, which greatly limits its application range.

The surface conductivity of the PEDOT:PSS film-forming acid or polar organic solvent can significantly improve the conductivity. However, surface treatment increases the steps, time and complexity of industrial production, thereby increasing the cost of preparation.

Summary of the invention

The object of the present invention is to solve the problems in the prior art and to provide a method for preparing a flexible transparent electrode on a large scale.

The technical solution adopted for achieving the object of the present invention is such a method for large-scale preparation of a flexible transparent electrode, which comprises the following steps:

1) Pretreatment of the substrate

The cleaned substrate is taken out, dried with high-purity nitrogen gas, and placed in an ultraviolet ozone treatment device for treatment;

2) Preparation of conductive solution based on doped PEDOT:PSS dispersion

PEDOT:PSS dispersion and acid solution are placed in a container for mixing to obtain a conductive solution based on the doped PEDOT:PSS dispersion;

The concentration of the acid in the conductive solution based on the doped PEDOT:PSS dispersion is in the range of 0.01 to 0.9 mol/L;

The concentration of the acid solution ranges from 0.8 to 2 mol/L;

3) Dispersing film

The conductive solution obtained in the step 2) is deposited on the substrate obtained in the step 1) by a coating process;

5) Transparent electrode heat treatment

The substrate covered with the conductive solution prepared in the step 3) is heated at a constant temperature, and naturally cooled to room temperature to obtain a transparent electrode;

The temperature of the constant temperature heating is 100 to 170 ° C, and the heating time is 5 to 120 minutes.

Further, the cleaning process of the glass substrate in the step 1) comprises: placing the divided square glass substrate on the Teflon cleaning bracket, placing the stent in the container, and sequentially adding deionized water to the container; Detergent, deionized water, acetone, the container is placed in an ultrasonic cleaner filled with water for cleaning, the deionized water washing step is repeated several times; after the cleaning is completed, the solution in the container is replaced with isopropanol, Store the cleaned glass substrate.

Further, the acid solution in the step 2) includes phosphoric acid (H ₃ PO ₄ ), sulfuric acid (H ₂ SO ₄ ), nitric acid (HNO ₃ ), pyrophosphoric acid (H ₄ P ₂ O ₇ ), perchloric acid (HClO). ₄ ), methanesulfonic acid (CH ₄ SO ₃ ), benzenesulfonic acid (C ₆ H ₆ O ₃ S), camphorsulfonic acid (C ₁₀ H ₁₆ O ₄ S), hydroxybenzenesulfonic acid (C ₆ H ₆ O ₄ S), 4-chlorobenzenesulfonic acid (C ₆ H ₅ ClO ₃ S), p-toluenesulfonic acid (C ₇ H ₈ O ₃ S), 4-methoxybenzenesulfonic acid (C ₇ H ₈ O ₄ S) , 4-ethylbenzenesulfonic acid (C ₈ H ₁₀ O ₃ S), B-naphthalenesulfonic acid (C ₁₀ H ₈ O ₃ S), dodecylbenzenesulfonic acid (C ₁₈ H ₃₀ O ₃ S), Inorganic or organic acids having phosphate, sulfate, nitrate, chlorate and sulfonate, such as phosphorous acid (H ₃ PO ₃ ), hexafluorophosphoric acid (HPF ₆ ), polyphosphoric acid (HO(HPO ₃ )H) One or more.

Further, the mixing process in the step 2) is stirring or sonication; the stirring speed ranges from 500 rpm to 1500 rpm, and the stirring time ranges from 5 min to 12 hr.

Further, the substrate in the step 1) comprises a flexible plastic transparent substrate in addition to the rigid glass or quartz base material; the plastic transparent substrate comprises polyethylene terephthalate (PET), polynaphthalene Ethylene glycol dicarboxylate (PEN) or polyimide substrate (PI).

Further, the coating process in the step 3) includes a blade preparation process, a bar coating process, a screen printing, a squeezing extrusion coating, an inkjet printing or a roll-to-roll process in addition to the spin coating method. Printed printing process suitable for large scale preparation.

It is worth noting that: through the direct mixing of proper acid solution and PEDOT:PSS stock solution, not only has good optical and electrical properties after film formation, but also its simple operation, it can be used for large-scale preparation of flexible transparent electrodes. The practical significance and commercial value.

The technical effect of the present invention is undoubtedly, and the present invention has the following advantages:

1) The present invention designs a novel PEDOT:PSS-based solution formulation. The present invention adds a certain proportion of an acid solution to an aqueous solution dispersion of PEDOT:PSS to form a completely transparent electrode solution. The electrode prepared by the solution can greatly reduce the sheet resistance and improve the conductivity of the electrode while maintaining the original light transmittance and flexibility;

2) The preparation process of the electrode of the invention is simple and easy to operate, no need for post-processing of the electrode, and can be prepared in a large amount in a short time, effectively shortening the production cycle and reducing the production cost, and realizing large-scale commercial production;

3) The invention can be processed by an ink printing preparation process, such as a spin coating method, a doctor blade preparation process, a bar coating process, a slit-type extrusion coating, an inkjet printing or a roll-to-roll printing process (roll-to-roll). Printing, etc., at room temperature or below 200 degrees Celsius, a transparent electrode film with excellent photoelectric properties and mechanical flexibility is directly prepared on different substrates, and the surface treatment after film formation is not required, thereby reducing the preparation process and production cycle. Reduced production costs and reduced energy consumption, providing a viable solution for large-scale manufacturing of flexible transparent electrodes.

4) The performance of the flexible transparent electrode prepared by the invention is greatly improved, and a new method for the later application of the photovoltaic device in the flexible direction is provided.

DRAWINGS

1 is a schematic view showing the structure of a doped PEDOT:PSS transparent electrode;

2 is a light transmittance curve of a transparent electrode prepared in Examples 1 to 5 in a wavelength range of 350 to 800 nm.

Detailed ways

The invention is further illustrated by the following examples, but it should not be understood that the scope of the invention described above is limited to the following examples. Various changes and modifications may be made without departing from the spirit and scope of the invention.

Example 1:

In the examples, PEDOT:PSS was purchased from Heraeus, Germany, product model PH1000. Phosphoric acid and other chemical reagents were purchased from Adamas.

A method for large-scale preparation of a flexible transparent electrode, comprising the steps of:

1) Pretreatment of the substrate

1.1) Cleaning of the glass substrate

Place the divided square glass substrate on the Teflon cleaning bracket, place the bracket in the beaker, add deionized water and detergent, deionized water, acetone to the beaker, and place the beaker in the beaker. Cleaning in a water ultrasonic cleaner, the deionized water washing step is repeated a plurality of times; after the cleaning is finished, the solution in the beaker is replaced with isopropyl alcohol to store the cleaned glass substrate;

1.2) Removal of the glass substrate

After the glass substrate stored in the isopropanone in the step 1.1) is taken out, dried with high-purity nitrogen gas, placed in an ultraviolet ozone treatment device, and then taken out;

2) Preparation of conductive solution based on doped PEDOT:PSS dispersion

PEDOT:PSS dispersion and phosphoric acid solution are placed in a container for mixing, and the container is placed on a magnetic stirrer to be stirred to obtain a conductive solution based on the doped PEDOT:PSS dispersion;

The concentration of phosphoric acid in the conductive solution based on the doped PEDOT:PSS dispersion is 0.6 mol/L;

The concentration of the phosphoric acid solution ranges from 1 to 2 mol/L;

3) Dispersing film

The ozone-treated glass substrate is placed at the center of rotation of the homogenizer, and the sample dispersion is evenly covered, and the squeezing machine is opened to carry out the enamel film;

4) Transparent electrode heat treatment

The substrate covered with the conductive solution prepared in the step 3) is heated at a constant temperature and naturally cooled to room temperature to obtain a transparent electrode as shown in FIG. 1;

The constant temperature heating temperature range was 150 ° C and the heating time was 15 min.

The transparent electrode prepared in this example was tested to obtain the results as shown in Table 1. As shown in FIG. 2, the transmittance curve of the transparent electrode prepared in the present embodiment is in the wavelength range of 350 to 800 nm.

Table 1

Example 2:

In the examples, PEDOT:PSS was purchased from Heraeus, Germany, product model PH1000. Sulfuric acid and other chemical reagents were purchased from Adamas.

A method for large-scale preparation of a flexible transparent electrode, comprising the steps of:

1) Pretreatment of the substrate

1.1) Cleaning of the glass substrate

Place the divided square glass substrate on the Teflon cleaning bracket, place the bracket in the beaker, add deionized water and detergent, deionized water, acetone to the beaker, and place the beaker in the beaker. Cleaning in a water ultrasonic cleaner, the deionized water washing step is repeated a plurality of times; after the cleaning is finished, the solution in the beaker is replaced with isopropyl alcohol to store the cleaned glass substrate;

1.2) Removal of the glass substrate

After the glass substrate stored in the isopropanone in the step 1.1) is taken out, dried with high-purity nitrogen gas, placed in an ultraviolet ozone treatment device, and then taken out;

2) Preparation of conductive solution based on doped PEDOT:PSS dispersion

PEDOT:PSS dispersion and sulfuric acid solution are placed in a container for mixing, and the container is placed on a magnetic stirrer to be stirred to obtain a conductive solution based on the doped PEDOT:PSS dispersion;

The concentration of sulfuric acid in the conductive solution based on the doped PEDOT:PSS dispersion is 0.1 mol / L;

The concentration of the sulfuric acid solution ranges from 0.8 to 1 mol/L;

3) Dispersing film

The ozone-treated glass substrate is placed at the center of rotation of the homogenizer, and the sample dispersion is evenly covered, and the squeezing machine is opened to carry out the enamel film;

4) Transparent electrode heat treatment

The substrate covered with the conductive solution prepared in the step 3) is heated at a constant temperature, and naturally cooled to room temperature to obtain a transparent electrode;

The constant temperature heating temperature range was 150 ° C and the heating time was 15 min.

The transparent electrode prepared in this example was tested to obtain the results as shown in Table 2. As shown in FIG. 2, the transmittance curve of the transparent electrode prepared in the present embodiment is in the wavelength range of 350 to 800 nm.

Table 2

Example 3:

In the examples, PEDOT:PSS was purchased from Heraeus, Germany, product model PH1000. Nitric acid and other chemical reagents were purchased from Adamas.

A method for large-scale preparation of a flexible transparent electrode, comprising the steps of:

1) Pretreatment of the substrate

1.1) Cleaning of the glass substrate

Place the divided square glass substrate on the Teflon cleaning bracket, place the bracket in the beaker, add deionized water and detergent, deionized water, acetone to the beaker, and place the beaker in the beaker. Cleaning in a water ultrasonic cleaner, the deionized water washing step is repeated a plurality of times; after the cleaning is finished, the solution in the beaker is replaced with isopropyl alcohol to store the cleaned glass substrate;

1.2) Removal of the glass substrate

After the glass substrate stored in the isopropanone in the step 1.1) is taken out, dried with high-purity nitrogen gas, placed in an ultraviolet ozone treatment device, and then taken out;

2) Preparation of conductive solution based on doped PEDOT:PSS dispersion

PEDOT:PSS dispersion and nitric acid solution are placed in a container for mixing, and the container is placed on a magnetic stirrer to be stirred to obtain a conductive solution based on the doped PEDOT:PSS dispersion;

The concentration of nitric acid in the conductive solution based on the doped PEDOT:PSS dispersion is 0.6 mol/L;

The concentration of the nitric acid solution ranges from 1 to 2 mol/L;

3) Dispersing film

The ozone-treated glass substrate is placed at the center of rotation of the homogenizer, and the sample dispersion is evenly covered, and the squeezing machine is opened to carry out the enamel film;

4) Transparent electrode heat treatment

The substrate covered with the conductive solution prepared in the step 3) is heated at a constant temperature, and naturally cooled to room temperature to obtain a transparent electrode;

The constant temperature heating temperature range is 120 ° C, and the heating time is 10 min.

The transparent electrode prepared in this example was tested to obtain the results as shown in Table 3. As shown in FIG. 2, the transmittance curve of the transparent electrode prepared in the present embodiment is in the wavelength range of 350 to 800 nm.

table 3

Example 4:

In the examples, PEDOT:PSS was purchased from Heraeus, Germany, product model PH1000. Pyrophosphoric acid and other chemical reagents were purchased from Adamas.

A method for large-scale preparation of a flexible transparent electrode, comprising the steps of:

1) Pretreatment of the substrate

1.1) Cleaning of the glass substrate

Place the divided square glass substrate on the Teflon cleaning bracket, place the bracket in the beaker, add deionized water and detergent, deionized water, acetone to the beaker, and place the beaker in the beaker. Cleaning in a water ultrasonic cleaner, the deionized water washing step is repeated a plurality of times; after the cleaning is finished, the solution in the beaker is replaced with isopropyl alcohol to store the cleaned glass substrate;

1.2) Removal of the glass substrate

After the glass substrate stored in the isopropanone in the step 1.1) is taken out, dried with high-purity nitrogen gas, placed in an ultraviolet ozone treatment device, and then taken out;

2) Preparation of conductive solution based on doped PEDOT:PSS dispersion

PEDOT:PSS dispersion and pyrophosphoric acid solution are placed in a container for mixing, and the container is placed on a magnetic stirrer to be stirred to obtain a conductive solution based on the doped PEDOT:PSS dispersion;

The concentration of pyrophosphoric acid in the conductive solution based on the doped PEDOT:PSS dispersion is 0.2 mol/L;

The concentration of the pyrophosphoric acid solution ranges from 0.8 to 1 mol/L;

3) Dispersing film

The ozone-treated glass substrate is placed at the center of rotation of the homogenizer, and the sample dispersion is evenly covered, and the squeezing machine is opened to carry out the enamel film;

4) Transparent electrode heat treatment

The substrate covered with the conductive solution prepared in the step 3) is heated at a constant temperature, and naturally cooled to room temperature to obtain a transparent electrode;

The constant temperature heating temperature range is 120 ° C, and the heating time is 10 min.

The transparent electrode prepared in this example was tested to obtain the results as shown in Table 4. As shown in FIG. 2, the transmittance curve of the transparent electrode prepared in the present embodiment is in the wavelength range of 350 to 800 nm.

Table 4

Example 5:

In the examples, PEDOT:PSS was purchased from Heraeus, Germany, product model PH1000. Perchloric acid and other chemicals were purchased from Adamas.

A method for large-scale preparation of a flexible transparent electrode, comprising the steps of:

1) Pretreatment of the substrate

1.1) Cleaning of the glass substrate

Place the divided square glass substrate on the Teflon cleaning bracket, place the bracket in the beaker, add deionized water and detergent, deionized water, acetone to the beaker, and place the beaker in the beaker. Cleaning in a water ultrasonic cleaner, the deionized water washing step is repeated a plurality of times; after the cleaning is finished, the solution in the beaker is replaced with isopropyl alcohol to store the cleaned glass substrate;

1.2) Removal of the glass substrate

After the glass substrate stored in the isopropanone in the step 1.1) is taken out, dried with high-purity nitrogen gas, placed in an ultraviolet ozone treatment device, and then taken out;

2) Preparation of conductive solution based on doped PEDOT:PSS dispersion

PEDOT:PSS dispersion and perchloric acid solution are placed in a container for mixing, and the container is placed on a magnetic stirrer to be stirred to obtain a conductive solution based on the doped PEDOT:PSS dispersion;

The concentration of perchloric acid in the conductive solution based on the doped PEDOT:PSS dispersion is 0.2 mol/L;

The concentration of the perchloric acid solution ranges from 0.8 to 1 mol/L;

3) Dispersing film

The ozone-treated glass substrate is placed at the center of rotation of the homogenizer, and the sample dispersion is evenly covered, and the squeezing machine is opened to carry out the enamel film;

4) Transparent electrode heat treatment

The substrate covered with the conductive solution prepared in the step 3) is heated at a constant temperature, and naturally cooled to room temperature to obtain a transparent electrode;

The constant temperature heating temperature range is 120 ° C, and the heating time is 10 min.

The transparent electrode prepared in this example was tested to obtain the results as shown in Table 5. As shown in FIG. 2, the transmittance curve of the transparent electrode prepared in the present embodiment is in the wavelength range of 350 to 800 nm.

table 5

Claims (6)

A method for large-scale preparation of a flexible transparent electrode, comprising the steps of: 1) Pretreatment of the substrate The cleaned substrate is taken out, dried with high-purity nitrogen gas, and placed in an ultraviolet ozone treatment device for treatment; 2) Preparation of conductive solution based on doped PEDOT:PSS dispersion PEDOT:PSS dispersion and acid solution are placed in a container for mixing to obtain a conductive solution based on the doped PEDOT:PSS dispersion; The concentration of the acid in the conductive solution based on the doped PEDOT:PSS dispersion is in the range of 0.01 to 0.9 mol/L; The concentration of the acid solution ranges from 0.8 to 2 mol/L; 3) Dispersing film The conductive solution obtained in the step 2) is deposited on the substrate obtained in the step 1) by a coating process; 5) Transparent electrode heat treatment The substrate covered with the conductive solution prepared in the step 3) is heated at a constant temperature, and naturally cooled to room temperature to obtain a transparent electrode; The temperature of the constant temperature heating is 100 to 170 ° C, and the heating time is 5 to 120 minutes. The method for preparing a flexible transparent electrode according to claim 1, wherein the cleaning process of the glass substrate in the step 1) comprises: placing the divided square glass substrate in polytetrafluoroethylene On the ethylene cleaning bracket, the stent is placed in a container, deionized water and detergent, deionized water, acetone are sequentially added to the container, and the container is placed in an ultrasonic cleaner filled with water for cleaning. The water washing step is repeated several times; after the cleaning is completed, the solution in the container is replaced with isopropyl alcohol to store the cleaned glass substrate. The method for preparing a flexible transparent electrode according to claim 1, wherein the acid solution in the step 2) comprises phosphoric acid, sulfuric acid, nitric acid, perchloric acid, methanesulfonic acid and benzenesulfonic acid. , camphorsulfonic acid, hydroxybenzenesulfonic acid, 4-chlorobenzenesulfonic acid, p-toluenesulfonic acid, 4-methoxybenzenesulfonic acid, 4-ethylbenzenesulfonic acid, B-naphthalenesulfonic acid, dodecylbenzene One or more of inorganic acids or organic acids having a phosphate, a sulfate, a nitrate, a chlorate, and a sulfonate, such as a sulfonic acid, pyrophosphoric acid, phosphorous acid, hexafluorophosphoric acid, or polyphosphoric acid. The method for preparing a flexible transparent electrode according to claim 1, wherein the mixing process in the step 2) is stirring or ultrasonic treatment; the stirring speed ranges from 500 rpm to 1500 rpm, and the stirring time is The range is from 5 min to 12 hr. The method for preparing a flexible transparent electrode according to claim 1, wherein the substrate in the step 1) comprises a flexible plastic transparent substrate in addition to a rigid glass or quartz base material; The plastic transparent substrate comprises polyethylene terephthalate, polyethylene naphthalate or a polyimide substrate. The method for preparing a flexible transparent electrode according to claim 1, wherein the coating process in the step 3) comprises a doctor blade preparation process and a bar coating method in addition to the spin coating method. A printing process suitable for large-scale preparation of processes, screen printing, squeezing extrusion coating, ink jet printing or roll-to-roll printing.

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