CN115418013B

CN115418013B - Conductive film and preparation method thereof

Info

Publication number: CN115418013B
Application number: CN202211119700.3A
Authority: CN
Inventors: 陶利松
Original assignee: Zhejiang Hete Photoelectricity Co ltd
Current assignee: Zhejiang Hete Photoelectricity Co ltd
Priority date: 2022-09-15
Filing date: 2022-09-15
Publication date: 2023-09-01
Anticipated expiration: 2042-09-15
Also published as: CN115418013A

Abstract

The application relates to the technical field of flexible-based transparent conductive film preparation, in particular to a conductive film and a preparation method thereof. A conductive film comprises a flexible substrate and a conductive film layer formed on the surface layer of the flexible substrate, wherein the conductive film layer contains conductive particles A and conductive particles B; the conductive particles A consist of an inorganic metal-based carrier and doped metal atoms, wherein the doped metal atoms are fixedly connected to the surface of the inorganic metal-based carrier; the mass ratio of the doped metal atoms to the inorganic metal-based carrier in the conductive particles is 1:5-8; the doped metal atom is at least one of Ag, zn and Al; the conductive particles B consist of inorganic silicon-based carriers and nanoscale metal clusters; the nanoscale metal clusters are at least one of silver nanoparticles and copper nanoparticles. The conductive film in the application is comparable to an ITO film in conductivity, the light transmittance is more than or equal to 80%, the preparation method is relatively simple, the production cost is lower, the realization of industrialized mass production is facilitated, and the application is easy to popularize in the market.

Description

Conductive film and preparation method thereof

Technical Field

The application relates to the technical field of flexible-based transparent conductive film preparation, in particular to a conductive film and a preparation method thereof.

Background

Currently, optoelectronic devices are evolving toward miniaturization, portability, and foldability. The flexible base Transparent Conductive Film (TCF) not only has photoelectric performance which is compared with that of a hard base, but also has the characteristics of being bendable, not fragile, light and thin, convenient to carry and the like, so that the flexible base transparent conductive film becomes a trend of future development, and has good application prospect in industrial production. The flexible base transparent conductive film has lower resistivity (p)<10 ^-3 Ω cm) and has a high transmittance in the visible light range (0=380 to 760 nm), has become an important component of solar cells in optoelectronic devices.

Currently, a transparent conductive film in the related art includes a substrate base layer and a conductive film layer fixedly connected to the substrate base layer. The substrate base layer is divided into a rigid substrate and a flexible substrate, wherein the rigid substrate comprises glass, ceramic, organic glass and the like, and the flexible substrate comprises a PET substrate, a PI substrate, a PC substrate, ultrathin flexible toughened glass and the like. The most widely used conductive film layer is still an Indium Tin Oxide (ITO) film. However, since indium resources are rare metals, indium resources are scarce and expensive, a high deposition temperature is required, and in addition, the deposited Indium Tin Oxide (ITO) film is fragile, which severely restricts the application and development of ITO materials in transparent conductive films of flexible substrates.

For this reason, many potential alternative materials have been developed by researchers, such as graphene, conductive polymers, carbon Nanotubes (CNT), metal films, and the like. However, the conductivity of the conductive polymer and the carbon nanotube film is not comparable to that of the ITO film. Graphene films prepared by Chemical Vapor Deposition (CVD) have excellent conductivity, but are expensive to produce, and the process is complex and unfavorable for mass production. The pure metal in the metal film has good conductivity, but is opaque, and can be used as a transparent conductive film only when the metal film is extremely thin (below 20 nm), and the metal film has low film strength and hardness and high preparation cost, and is mainly used in the field of electromagnetic shielding at present. To this end, the present application provides a novel conductive film.

Disclosure of Invention

In order to solve the technical problems, the application provides a conductive film and a preparation method thereof.

In a first aspect, the present application provides a conductive film, which is implemented by the following technical scheme:

the conductive film comprises a flexible substrate and a conductive film layer formed on the surface layer of the flexible substrate, wherein the conductive film layer contains conductive particles A and conductive particles B, and the conductive particles A and the conductive particles B form a conductive network; the particle size of the conductive particles A is controlled to be 10-200nm; the particle size of the conductive particles B is controlled to be 100-250nm; the conductive particles A consist of an inorganic metal-based carrier and doped metal atoms, and the doped metal atoms are fixedly connected to the surface of the inorganic metal-based carrier; the mass ratio of the doped metal atoms to the inorganic metal-based carrier in the conductive particles is 1:5-8; the doped metal atoms are at least one of Ag, zn and Al; the conductive particles B consist of an inorganic silicon-based carrier and nanoscale metal clusters; the nanoscale metal cluster is at least one of silver nanoparticle and copper nanoparticle.

By adopting the technical scheme, the conductive film is comparable to the ITO film in conductivity, the light transmittance is more than or equal to 80 percent, the preparation method is relatively simple, the production cost is low, the industrialized mass production is convenient to realize, and the conductive film is easy to popularize in the market.

Preferably, the material is prepared from the following raw materials in parts by weight: 80-100 parts of organic polymer resin, 4-8 parts of conductive particles A and 2-4 parts of conductive particles B; the organic polymer resin is one of PET, PI, TPU.

By adopting the technical scheme, the flexibility and the light transmittance of the application can be ensured, and the prepared conductive film is comparable to an ITO film and has the potential of replacing the conventional ITO film.

Preferably, the inorganic metal-based carrier is one of an inorganic zinc-based carrier and an inorganic tin-based carrier with granularity controlled between 10 and 200 nm; the inorganic zinc-based carrier is wurtzite phase zinc dioxide; the inorganic tin-based carrier is tin dioxide with a rutile structure.

The forbidden bandwidth of tin dioxide is about 3.55-4.0eV, and has very high transmission performance to visible light, which can reach more than 90%, and meanwhile, due to high carrier concentration (10 ¹⁵ -10 ¹⁸ cm ³ ) The SnO2 film has high reflectivity in the middle infrared and far infrared regions and mobility of 5-30cm ² and/Vs, the resistivity is 10 < -4 > -10 < -3 > Ω cm. SnO2 has stable chemical property and extremely strong chemical corrosion resistance. The wurtzite phase zinc dioxide direct band gap I-VI semiconductor has larger forbidden band width eg=3.1-3.6 eV, larger exciton binding energy (60 meV) and piezoelectric effect, and has photoelectric characteristics comparable with ITO.

Preferably, the inorganic metal-based carrier is tin dioxide with a rutile structure, and when the doped metal atoms are Ag and Zn; the mass percentage of Ag in the doped metal atoms is 80-95%; when the doped metal atoms are Ag and Al; the mass percentage of Ag in the doped metal atoms is 75-90%; when the doped metal atoms are Ag, zn and Al; the mass percentage of Al in the doped metal atoms is 5-10%; the mass percentage of Zn in the doped metal atoms is 10-15%.

Through the doping optimization scheme, the conductivity of the application can be improved, and the overall quality of the application can be improved.

Preferably, the preparation method of the conductive particles A comprises the following steps:

s1, roasting an inorganic metal-based carrier at 400-600 ℃ and 0.8-1.0Mpa for 10-15min, cooling, and performing planetary ball milling until the granularity is 10-200nm for later use;

s2, preparing a precursor: dropwise adding 20-40mL of 3-5% ammonia water solution into the solution at a speed of 80-120 mu L/s, stirring, wherein the metal salt is at least one of silver nitrate, zinc nitrate and aluminum nitrate, the concentration of the metal salt solution is 50-200 g/L, the solvent of the metal salt solution is deionized water, stirring for 2-5 h, heating to 60 ℃ within 20-40min, and continuing stirring for 2-4h to obtain a mixed solution;

S3, synthesizing a conductive particle precursor by in-situ coprecipitation: adding the precursor of the inorganic metal-based carrier in S1 into the mixed solution in S2 according to the mass ratio of the doped metal atoms to the inorganic metal-based carrier of 1:5-8, reacting for 20-28h at 120-150 ℃, cooling to room temperature after the reaction is finished, centrifugally separating to obtain a solid product, washing the obtained solid product with ethanol and water for at least 3 times respectively, then vacuum drying for 3-5h at 100 ℃, and performing planetary ball milling to obtain conductive particle powder with the granularity of 10-150 nm;

s4, in-situ generating finished conductive particles by a one-step method: and (3) placing the conductive particle powder obtained in the step (S3) in the atmosphere of 3-10% hydrogen-argon mixture, heating at 350-800 ℃ for 2-4h, cooling to room temperature, and grinding to obtain the finished conductive particles A.

By adopting the technical scheme, the conductive particles A can be prepared in batches, the preparation process difficulty of the conductive particles A is relatively low, the production cost is relatively low, and the overall production cost can be further reduced.

In a second aspect, the present application provides a method for preparing a conductive film, which is implemented by the following technical scheme:

a preparation method of a conductive film comprises the following steps:

step one, drying organic polymer resin, and carrying out surface modification treatment on conductive particles A and conductive particles B;

Uniformly mixing the dried organic polymer resin with conductive particles A and B which are subjected to surface modification treatment accurately in a metering way, extruding, and granulating to obtain film-making master batch;

extruding, casting and cooling the film-making master batch to obtain a semi-finished film;

and fourthly, heating the semi-finished film to 3-8 ℃ above Tg to enable molecular chain links in the semi-finished film to freely move, performing particle migration treatment in a uniform electric field to form a conductive film layer on the surface layer of the semi-finished film, performing particle migration treatment for 3-5h, and cooling to normal temperature to obtain the finished conductive film.

By adopting the technical scheme, the ITO film with conductivity comparable to that of the ITO film can be prepared, the light transmittance is more than or equal to 85 percent, and the conductive film can replace the conventional ITO film. In addition, the preparation method is relatively simple, has lower production cost, is convenient for realizing industrialized mass production, and is easy for market popularization.

Preferably, the specific operation of the surface modification treatment of the conductive particles A and the conductive particles B in the step one is that the conductive particles A and the conductive particles B are placed in 5-8g/L of propyl dioleate acyloxy (dioctyl phosphate acyloxy) titanate aqueous solution, ultrasonic treatment is carried out for 30-60min, and the conductive particles A and the conductive particles B are taken out and dried for standby.

By adopting the technical scheme, the compatibility of the conductive particles A and B with the organic polymer resin can be improved, and the quality of the prepared conductive film is further ensured.

Preferably, the semi-finished film is loaded into a quartz mold, one end of the quartz mold is opened and the other end of the quartz mold is closed, the quartz mold loaded with the semi-finished film is placed in an environment of 3-8 ℃ above Tg, positive electrode plates are placed on the opening end face of the quartz mold in parallel, the linear distance between the opening end face of the quartz mold and the lower surface of the positive electrode plates is 0.1-4mm, negative electrode plates are placed on the closing end face of the quartz mold in parallel, the linear distance between the closing end face of the quartz mold and the lower surface of the negative electrode plates is above 15mm, and the electric strength formed between the positive electrode plates and the negative electrode plates is controlled to be 10 ⁴ -10 ⁶ N/C, particle migration treatment for 3-5h to form conductive film layer on the surface of semi-finished film, and coolingCooling the gas to 40-45 ℃ at 10-15 ℃/min, and naturally cooling to normal temperature to obtain the finished conductive film.

By adopting the technical scheme, one surface layer surface of the finished electrothermal film is enriched with the conductive particles A and the conductive particles B to form a conductive network structure, and then the flexible transparent conductive film with better conductivity is obtained.

Preferably, the finished electrothermal film in the fourth step is treated by adopting an irradiation crosslinking process to obtain the finished electrothermal film; the irradiation crosslinking process uses cobalt as a radiation source, an electron gun emits low-energy electron beams, the energy is increased to 8-12MeV through an accelerator and then is output, the surface of a semi-finished film material under the accelerator is directly irradiated, the irradiation dose is controlled to be 10-15Mrad, and the crosslinking treatment time is controlled to be 6-10s.

The conductive film treated by the irradiation crosslinking process is improved in mechanical property, weather resistance, conductivity and flame retardance, and the quality of the conductive film can be improved.

In summary, the application has the following advantages:

1. the conductive film in the application is comparable to an ITO film in conductivity, the light transmittance is more than or equal to 85%, and the conductive film has the potential of replacing the conventional ITO film.

2. The preparation method is relatively simple, has lower production cost, is convenient for realizing industrialized mass production, and is easy for market popularization.

Detailed Description

The present application will be described in further detail with reference to comparative examples and examples.

Preparation example

Preparation example 1

The particle diameter of the conductive particles A is controlled to be 10-50nm, and the conductive particles A consist of an inorganic metal-based carrier and doped metal atoms. The inorganic metal-based carrier is tin dioxide with a rutile structure, the doped metal atoms are Ag and Zn, the mass percentage of Ag in the doped metal atoms is 85%, and the mass percentage of Zn is 15%.

A method for preparing conductive particles a, comprising the steps of:

s1, roasting rutile structure tin dioxide at 400 ℃ and 1.0Mpa for 15min, cooling, and performing planetary ball milling until the granularity is 10-50nm to obtain activated rutile structure tin dioxide for later use;

s2, preparing a precursor: dropwise adding 40ml of 5% ammonia water solution into 100g/L of silver nitrate/zinc nitrate water solution at a speed of 100 mu L/s, stirring, wherein the mass ratio of the silver nitrate to the zinc nitrate is 0.85:0.15, stirring for 4 hours, heating to 60 ℃ within 30 minutes, and continuously stirring for 3 hours to obtain a mixed solution;

s3, synthesizing a conductive particle precursor by in-situ coprecipitation: adding the tin dioxide precursor with the activated rutile structure in S1 into the mixed solution in S2 according to the mass ratio of the doped metal atoms Ag to Zn to the tin dioxide of 0.85:0.15:5, reacting for 26 hours at 140 ℃, cooling to room temperature after the reaction is finished, centrifugally separating to obtain a solid product, washing the obtained solid product with ethanol and water for 3 times respectively, then vacuum-drying for 4 hours at 100 ℃, and performing planetary ball milling to obtain conductive particle powder with the granularity of 10-50 nm;

s4, in-situ generating finished conductive particles by a one-step method: and (3) placing the conductive particle powder obtained in the step (S3) in the atmosphere of 5% hydrogen-argon mixture, heating at 420 ℃ for 4 hours, cooling to room temperature, and grinding to obtain the finished conductive particles with the granularity of 10-50 nm.

Preparation example 2

Preparation 2 differs from preparation 1 in that:

the inorganic metal-based carrier is tin dioxide with a rutile structure, the doped metal atoms are Ag and Zn, the mass percentage of Ag in the doped metal atoms is 80%, and the mass percentage of Zn is 20%.

S2, preparing a precursor: dropwise adding 40ml of 5% ammonia water solution into 100g/L of silver nitrate/zinc nitrate water solution at a speed of 100 mu L/s, stirring, wherein the mass ratio of the silver nitrate to the zinc nitrate is 0.8:0.2, stirring for 4 hours, heating to 60 ℃ within 30 minutes, and continuously stirring for 3 hours to obtain a mixed solution;

s3, synthesizing a conductive particle precursor by in-situ coprecipitation: adding the tin dioxide precursor with the activated rutile structure in S1 into the mixed solution in S2 according to the mass ratio of the doped metal atoms Ag to Zn to the tin dioxide of 0.8:0.2:5, reacting for 26 hours at 140 ℃, cooling to room temperature after the reaction is finished, centrifugally separating to obtain a solid product, washing the obtained solid product with ethanol and water for 3 times respectively, then vacuum drying for 4 hours at 100 ℃, and performing planetary ball milling to obtain conductive particle powder with the granularity of 10-50 nm.

Preparation example 3

Preparation 3 differs from preparation 1 in that:

the particle diameter of the conductive particles A is controlled to be 10-50nm, and the conductive particles A consist of an inorganic metal-based carrier and doped metal atoms. The inorganic metal-based carrier is tin dioxide with a rutile structure, the doped metal atoms are Ag and Zn, the mass percentage of Ag in the doped metal atoms is 88%, and the mass percentage of Zn is 12%.

S2, preparing a precursor: dropwise adding 40ml of 5% ammonia water solution into 100g/L of silver nitrate/zinc nitrate water solution at a speed of 100 mu L/s, stirring, wherein the mass ratio of the silver nitrate to the zinc nitrate is 0.88:0.12, stirring for 4 hours, heating to 60 ℃ within 30 minutes, and continuously stirring for 3 hours to obtain a mixed solution;

s3, synthesizing a conductive particle precursor by in-situ coprecipitation: adding the tin dioxide precursor with the activated rutile structure in S1 into the mixed solution in S2 according to the mass ratio of the doped metal atoms Ag to Zn to the tin dioxide of 0.88:0.12:5, reacting for 26 hours at 140 ℃, cooling to room temperature after the reaction is finished, centrifugally separating to obtain a solid product, washing the obtained solid product with ethanol and water for 3 times respectively, then vacuum drying for 4 hours at 100 ℃, and performing planetary ball milling to obtain conductive particle powder with the granularity of 10-50 nm.

Preparation example 4

Preparation example 4 differs from preparation example 1 in that:

the particle diameter of the conductive particles A is controlled to be 10-50nm, and the conductive particles A consist of an inorganic metal-based carrier and doped metal atoms. The inorganic metal-based carrier is tin dioxide with a rutile structure, the doped metal atoms are Ag and Zn, the mass percentage of Ag in the doped metal atoms is 95%, and the mass percentage of Zn is 5%.

S2, preparing a precursor: dropwise adding 40ml of 5% ammonia water solution into 100g/L of silver nitrate/zinc nitrate water solution at a speed of 100 mu L/s, stirring, wherein the mass ratio of the silver nitrate to the zinc nitrate is 0.95:0.05, stirring for 4 hours, heating to 60 ℃ within 30 minutes, and continuously stirring for 3 hours to obtain a mixed solution;

S3, synthesizing a conductive particle precursor by in-situ coprecipitation: adding the tin dioxide precursor with the activated rutile structure in S1 into the mixed solution in S2 according to the mass ratio of the doped metal atoms Ag to Zn to the tin dioxide of 0.95:0.05:5, reacting for 26 hours at 140 ℃, cooling to room temperature after the reaction is finished, centrifugally separating to obtain a solid product, washing the obtained solid product with ethanol and water for 3 times respectively, then vacuum drying for 4 hours at 100 ℃, and performing planetary ball milling to obtain conductive particle powder with the granularity of 10-50 nm.

Preparation example 5

Preparation 5 differs from preparation 1 in that:

the inorganic metal-based carrier is tin dioxide with a rutile structure, the doped metal atoms are Ag and Al, the mass percentage of Ag in the doped metal atoms is 75%, and the mass percentage of Al is 25%.

S2, preparing a precursor: dropwise adding 40ml of 5% ammonia water solution into 100g/L of silver nitrate/aluminum nitrate water solution at a speed of 100 mu L/s, stirring, wherein the mass ratio of the silver nitrate to the aluminum nitrate is 0.75:0.25, stirring for 4 hours, heating to 60 ℃ within 30 minutes, and continuously stirring for 3 hours to obtain a mixed solution;

s3, synthesizing a conductive particle precursor by in-situ coprecipitation: adding the tin dioxide precursor with the activated rutile structure in S1 into the mixed solution in S2 according to the mass ratio of the doped metal atoms Ag to Zn to the tin dioxide of 0.5:0.25:5, reacting for 26 hours at 140 ℃, cooling to room temperature after the reaction is finished, centrifugally separating to obtain a solid product, washing the obtained solid product with ethanol and water for 3 times respectively, then vacuum drying for 4 hours at 100 ℃, and performing planetary ball milling to obtain conductive particle powder with the granularity of 10-50 nm.

Preparation example 6

Preparation 6 differs from preparation 5 in that:

the inorganic metal-based carrier is tin dioxide with a rutile structure, the doped metal atoms are Ag and Al, the mass percentage of Ag in the doped metal atoms is 82%, and the mass percentage of Al is 18%.

Preparation example 7

Preparation 7 differs from preparation 5 in that:

the inorganic metal-based carrier is tin dioxide with a rutile structure, the doped metal atoms are Ag and Al, the mass percentage of the Ag in the doped metal atoms is 90%, and the mass percentage of the Al is 10%.

Preparation example 8

Preparation 8 differs from preparation 1 in that:

the particle diameter of the conductive particles A is controlled to be 10-50nm, and the conductive particles A consist of an inorganic metal-based carrier and doped metal atoms. The inorganic metal-based carrier is tin dioxide with a rutile structure, the doped metal atoms are Ag, zn and Al, the mass percentage of Ag in the doped metal atoms is 75%, the mass percentage of Zn is 15%, and the mass percentage of Al is 10%.

S2, preparing a precursor: dropwise adding 40ml of 5% ammonia water solution into 100g/L of silver nitrate/zinc nitrate/aluminum nitrate water solution at a speed of 100 mu L/s, stirring, wherein the mass ratio of the silver nitrate to the zinc nitrate to the aluminum nitrate is 0.75:0.15:0.1, heating to 60 ℃ within 30min after stirring for 4h, and continuously stirring for 3h to obtain a mixed solution;

S3, synthesizing a conductive particle precursor by in-situ coprecipitation: adding the tin dioxide precursor with the activated rutile structure in S1 into the mixed solution in S2 according to the mass ratio of the doped metal atoms Ag, zn, al and tin dioxide of 0.75:0.15:0.1:5, reacting for 26 hours at 140 ℃, cooling to room temperature after the reaction is finished, centrifugally separating to obtain a solid product, washing the obtained solid product with ethanol and water for 3 times respectively, then drying in vacuum at 100 ℃ for 4 hours, and performing planetary ball milling to obtain conductive particle powder with the granularity of 10-50 nm.

Preparation example 9

Preparation 9 differs from preparation 8 in that:

the particle diameter of the conductive particles A is controlled to be 10-50nm, and the conductive particles A consist of an inorganic metal-based carrier and doped metal atoms. The inorganic metal-based carrier is tin dioxide with a rutile structure, the doped metal atoms are Ag, zn and Al, the mass percentage of Ag in the doped metal atoms is 80%, the mass percentage of Zn is 12%, and the mass percentage of Al is 8%.

Preparation example 10

Preparation 10 differs from preparation 8 in that:

s3, synthesizing a conductive particle precursor by in-situ coprecipitation: adding the tin dioxide precursor with the activated rutile structure in S1 into the mixed solution in S2 according to the mass ratio of the doped metal atoms Ag, zn, al and tin dioxide of 0.75:0.15:0.1:6, reacting for 26 hours at 140 ℃, cooling to room temperature after the reaction is finished, centrifugally separating to obtain a solid product, washing the obtained solid product with ethanol and water for 3 times respectively, then drying in vacuum at 100 ℃ for 4 hours, and performing planetary ball milling to obtain conductive particle powder with the granularity of 10-50 nm.

PREPARATION EXAMPLE 11

Preparation 11 differs from preparation 8 in that:

s3, synthesizing a conductive particle precursor by in-situ coprecipitation: adding the tin dioxide precursor with the activated rutile structure in S1 into the mixed solution in S2 according to the mass ratio of the doped metal atoms Ag, zn, al and tin dioxide of 0.75:0.15:0.1:8, reacting for 26 hours at 140 ℃, cooling to room temperature after the reaction is finished, centrifugally separating to obtain a solid product, washing the obtained solid product with ethanol and water for 3 times respectively, then drying in vacuum at 100 ℃ for 4 hours, and performing planetary ball milling to obtain conductive particle powder with the granularity of 10-50 nm.

Preparation example 12

Preparation 12 differs from preparation 1 in that:

the particle diameter of the conductive particles A is controlled to be 10-50nm, and the conductive particles A consist of an inorganic metal-based carrier and doped metal atoms. The inorganic metal-based carrier is wurtzite phase zinc dioxide, and the doped metal atoms are Ag and Al, wherein the mass percentage of the Ag is 95%.

S2, preparing a precursor: dropwise adding 40ml of 5% ammonia water solution into 100g/L of silver nitrate/aluminum nitrate water solution at a speed of 100 mu L/s, stirring, wherein the mass ratio of the silver nitrate to the aluminum nitrate is 0.95:0.05, stirring for 4 hours, heating to 60 ℃ within 30 minutes, and continuously stirring for 3 hours to obtain a mixed solution;

Preparation example 13

Preparation 13 differs from preparation 1 in that:

the particle diameter of the conductive particles A is controlled to be 10-50nm, and the conductive particles A consist of an inorganic metal-based carrier and doped metal atoms. The inorganic metal-based carrier is wurtzite phase zinc dioxide, and the doped metal atoms are Ag and Al, wherein the mass percentage of the Ag is 92%.

S2, preparing a precursor: dropwise adding 40ml of 5% ammonia water solution into 100g/L of silver nitrate/aluminum nitrate water solution at a speed of 100 mu L/s, stirring, wherein the mass ratio of the silver nitrate to the aluminum nitrate is 0.92:0.08, stirring for 4 hours, heating to 60 ℃ within 30 minutes, and continuously stirring for 3 hours to obtain a mixed solution;

s3, synthesizing a conductive particle precursor by in-situ coprecipitation: adding the tin dioxide precursor with the activated rutile structure in S1 into the mixed solution in S2 according to the mass ratio of the doped metal atoms Ag to Zn to the tin dioxide of 0.92:0.08:5, reacting for 26 hours at 140 ℃, cooling to room temperature after the reaction is finished, centrifugally separating to obtain a solid product, washing the obtained solid product with ethanol and water for 3 times respectively, then vacuum drying for 4 hours at 100 ℃, and performing planetary ball milling to obtain conductive particle powder with the granularity of 10-50 nm.

Preparation 14 (comparative)

Preparation 14 differs from preparation 1 in that:

the particle diameter of the conductive particles A is controlled to be 10-50nm, and the conductive particles A consist of an inorganic metal-based carrier and doped metal atoms. The inorganic metal-based carrier is tin dioxide with a rutile structure, the doped metal atoms are Ag and Zn, the mass percentage of Ag in the doped metal atoms is 98%, and the mass percentage of Zn is 2%.

Preparation 15 (comparative)

Preparation 15 differs from preparation 5 in that:

the inorganic metal-based carrier is tin dioxide with a rutile structure, the doped metal atoms are Ag and Al, the mass percentage of Ag in the doped metal atoms is 95%, and the mass percentage of Al is 5%.

Preparation 16 (comparative)

Preparation 16 differs from preparation 8 in that:

the particle diameter of the conductive particles A is controlled to be 10-50nm, and the conductive particles A consist of an inorganic metal-based carrier and doped metal atoms. The inorganic metal-based carrier is tin dioxide with a rutile structure, the doped metal atoms are Ag, zn and Al, the mass percentage of Ag in the doped metal atoms is 78%, the mass percentage of Zn is 20%, and the mass percentage of Al is 2%.

Preparation 17 (comparative)

Preparation 17 differs from preparation 8 in that:

s3, synthesizing a conductive particle precursor by in-situ coprecipitation: adding the tin dioxide precursor with the activated rutile structure in S1 into the mixed solution in S2 according to the mass ratio of the doped metal atoms Ag, zn, al and tin dioxide of 0.75:0.15:0.1:10, reacting for 26 hours at 140 ℃, cooling to room temperature after the reaction is finished, centrifugally separating to obtain a solid product, washing the obtained solid product with ethanol and water for 3 times respectively, then drying in vacuum at 100 ℃ for 4 hours, and performing planetary ball milling to obtain conductive particle powder with the granularity of 10-50 nm.

PREPARATION EXAMPLE 18

Preparation 18 differs from preparation 1 in that:

the particle diameter of the conductive particles A is controlled to be 10-50nm, and the conductive particles A consist of an inorganic metal-based carrier and doped metal atoms. The inorganic metal-based carrier is tin dioxide with a rutile structure, and the doped metal atom is Ag.

Preparation example 19

The conductive particles B are composed of inorganic metal-based carriers and nanoscale metal clusters, wherein the inorganic metal-based carriers are silicon dioxide with the particle size of 80-120nm, the nanoscale metal clusters are nano silver particles, and the conductive particles are formed on the surface of the silicon dioxide through a conventional chemical liquid phase deposition method.

A method for preparing conductive particles B, comprising the steps of:

adding 2kg of silicon dioxide into 10kg of hydrochloric acid solution with the concentration of 6mol/L, dispersing for 30min at the rotating speed of 160rpm, standing for 1h after uniform mixing, removing supernatant, leaving a precipitate at the lower layer, washing the obtained precipitate with deionized water for 2 times, and performing filter pressing dehydration to obtain a coarsened material;

adding the coarsened material into 6kg deionized water, heating to 70 ℃ while stirring to obtain a feed liquid, then stirring the feed liquid at 160rpm for 0.5h under the condition that the feed liquid is kept at 70 ℃, and then adjusting the pH value of the feed liquid to 1.6-1.8 by using a hydrochloric acid solution with the concentration of 6 mol/L;

2kg of SnCl with the weight percentage of 2.5% is added under the condition that the temperature of the feed liquid is 70 DEG C ₄ Gradually dripping the solution into the feed liquid, finishing dripping within 1h, and simultaneously adopting 6mol/L hydrochloric acid to adjust the pH value of the feed liquid to be between 1.6 and 1.8, wherein SnCl is the catalyst ₄ After the solution is added dropwise, 5wt% NaOH solution is added to regulate the pH value of the feed liquid to 2.0-2.2, the temperature is controlled at 80 ℃, and TiCl with the concentration of 4mol/L is added ₄ The pH value of the feed liquid is kept between 2.0 and 2.2 by using a solution of 5wt% NaOH ₄ The amount of solution was 1.6kg TiCl ₄ Dripping the solution, stirring uniformly, press-filtering and dehydrating to obtain an activated mixed material;

the method for preparing the silver ammonia solution comprises the following steps: 14g of AgNO by weight ₃ Mixing with 250g of NaOH solution with the weight percentage concentration of 5%, uniformly stirring, then dripping ammonia water with the weight percentage concentration of 12.5% until the solution is clear, and regulating the pH value to 12.5 by nitric acid with the weight percentage concentration of 15.5% to obtain silver-ammonia solution; preparing a reducing solution, namely mixing 160g of anhydrous acetaldehyde and 4840g of ethanol solution with the weight percentage concentration of 30%, and uniformly stirring to obtain the reducing solution;

placing the activated mixed material into silver ammonia solution to perform silver mirror reaction to obtain a mixed material with nano metal silver surface modified: adding activated mixed materials into a reaction container, adding 6kg of deionized water into the reaction container, regulating the temperature of the materials in the reaction container to 28 ℃, adding 1g of sodium thiosulfate, stirring for 1h, gradually adding a reducing solution into the reaction container, finishing the addition within 1.5h, stirring for 1.0h, regulating the pH value of the materials in the reaction container to 12-13, adding the prepared silver-ammonia solution into the reaction container at a stirring speed of 360rpm at a dropping speed of 5mL/min, finishing the addition of the silver-ammonia solution within 1h, controlling the temperature of the materials in the reaction container to 25 ℃ in the process of adding the silver-ammonia solution, regulating the pH value of the materials in the reaction container by nitric acid, keeping the pH value of the materials in the reaction container between 12 and 13, after the addition of the silver-ammonia solution, preserving heat for 1h at the stirring speed of 360rpm, filtering out powder, and drying to obtain conductive particles B.

Examples

Example 1

The application discloses a conductive film, which comprises a flexible substrate and a conductive film layer formed on the surface layer of the flexible substrate. The conductive film layer contains conductive particles A and conductive particles B, and the conductive particles A and the conductive particles B form a conductive network. The conductive film is prepared from the following raw materials in parts by weight: 92.5 parts of PET, 5 parts of conductive particles A in preparation example 1, 2 parts of conductive particles B in preparation example 19, and 0.5 part of antioxidant 1010.

A preparation method of a conductive film comprises the following steps:

step one, drying PET resin at 100 ℃ for 6 hours for later use;

and simultaneously carrying out surface modification treatment on the conductive particles A and B: placing the conductive particles A in preparation example 1 and the conductive particles B in preparation example 18 in 5g/L of propyl dioleate acyloxy (dioctyl phosphate acyloxy) titanate aqueous solution, performing ultrasonic treatment for 30min, taking out, and drying for later use;

step two, evenly mixing 1850g of the dried PET resin with 100g of conductive particles A in preparation example 1, 40g of conductive particles B in preparation example 18 and 10g of antioxidant 1010, which are accurately subjected to surface modification treatment, placing the mixture in a double-screw extruder, wherein the temperature of the mixture is 240-250 ℃, the temperature of the mixture is 255-260 ℃, the temperature of the mixture is 265-270 ℃, the temperature of the mixture is 275-280, the temperature of the mixture is 280-282 ℃, the temperature of the mixture is 282-283 ℃, extruding the mixture, water-cooling the mixture and granulating the mixture to obtain film-making master batches;

Step three, drying the film-making master batch at 100 ℃ for 6.0h, putting the dried film-making master batch into a double-screw extruder, setting the film-making master batch at 240-250 ℃ in a first heating temperature zone, 255-260 ℃ in a second heating temperature zone, 265-270 ℃ in a third heating temperature zone, 275-280 in a fourth heating temperature zone, 280-282 ℃ in the first heating temperature zone, 282-283 ℃ in a die head, extruding the extruded hot-melt material to obtain a prefabricated film, longitudinally stretching the prefabricated film at 115 ℃ by a longitudinal stretching machine at a longitudinal stretching ratio of 2.8, transversely stretching the prefabricated film at 115 ℃ by a transverse stretching machine at a transverse stretching ratio of 3.0, setting the film at 230 ℃ for 15s, annealing the film in an electrothermal blowing drying box at 95 ℃ for 10min, and naturally cooling the film to obtain a semi-finished BOPET film with a thickness of 80+/-5 micrometers;

loading the semi-finished film into a quartz mold, wherein one end of the quartz mold is open, the other end of the quartz mold is closed, the quartz mold for loading the semi-finished film is placed in an environment of 168 ℃, positive electrode plates are parallelly arranged on the opening end faces of the quartz mold, the straight line distance between the opening end faces of the quartz mold and the lower surface of the positive electrode plates is 0.5mm, negative electrode plates are parallelly arranged on the closing end faces of the quartz mold, the straight line distance between the closing end faces of the quartz mold and the lower surface of the negative electrode plates is 18mm, and the electric strength formed between the positive electrode plates and the negative electrode plates is controlled to be 8 x 10 ⁵ N/C, particle migration treatment is carried out for 5 hours, a conductive film layer is formed on the surface layer of the semi-finished film, then cooling gas is introduced, the temperature is reduced to 45 ℃ at 12 ℃/min, and natural cooling is carried out to normal temperature, so that the finished conductive film is obtained.

Example 2

Example 2 differs from example 1 in that: the conductive film is prepared from the following raw materials in parts by weight: 92.5 parts of PET, 5 parts of conductive particles A in preparation example 2, 2 parts of conductive particles B in preparation example 19, and 0.5 part of antioxidant 1010.

Example 3

Example 3 differs from example 1 in that: the conductive film is prepared from the following raw materials in parts by weight: 92.5 parts of PET, 5 parts of conductive particles A in preparation example 3, 2 parts of conductive particles B in preparation example 19, and 0.5 part of antioxidant 1010.

Example 4

Example 2 differs from example 1 in that: the conductive film is prepared from the following raw materials in parts by weight: 92.5 parts of PET, 5 parts of conductive particles A in preparation example 4, 2 parts of conductive particles B in preparation example 19, and 0.5 part of antioxidant 1010.

Example 5

Example 5 differs from example 1 in that: the conductive film is prepared from the following raw materials in parts by weight: 92.5 parts of PET, 5 parts of conductive particles A in preparation example 5, 2 parts of conductive particles B in preparation example 19, and 0.5 part of antioxidant 1010.

Example 6

Example 6 differs from example 1 in that: the conductive film is prepared from the following raw materials in parts by weight: 92.5 parts of PET, 5 parts of conductive particles A in preparation example 6, 2 parts of conductive particles B in preparation example 19, and 0.5 part of antioxidant 1010.

Example 7

Example 7 differs from example 1 in that: the conductive film is prepared from the following raw materials in parts by weight: 92.5 parts of PET, 5 parts of conductive particles A in preparation example 7, 2 parts of conductive particles B in preparation example 19, and 0.5 part of antioxidant 1010.

Example 8

Example 8 differs from example 1 in that: the conductive film is prepared from the following raw materials in parts by weight: 92.5 parts of PET, 5 parts of conductive particles A in preparation example 8, 2 parts of conductive particles B in preparation example 19, and 0.5 part of antioxidant 1010.

Example 9

Example 9 differs from example 1 in that: the conductive film is prepared from the following raw materials in parts by weight: 92.5 parts of PET, 5 parts of conductive particles A in preparation example 9, 2 parts of conductive particles B in preparation example 19, and 0.5 part of antioxidant 1010.

Example 10

Example 10 differs from example 1 in that: the conductive film is prepared from the following raw materials in parts by weight: 92.5 parts of PET, 5 parts of conductive particles A in preparation example 10, 2 parts of conductive particles B in preparation example 19, and 0.5 part of antioxidant 1010.

Example 11

Example 11 differs from example 1 in that: the conductive film is prepared from the following raw materials in parts by weight: 92.5 parts of PET, 5 parts of conductive particles A in preparation example 11, 2 parts of conductive particles B in preparation example 19, and 0.5 part of antioxidant 1010.

Example 12

Example 12 differs from example 1 in that: the conductive film is prepared from the following raw materials in parts by weight: 92.5 parts of PET, 5 parts of conductive particles A in preparation example 12, 2 parts of conductive particles B in preparation example 19, and 0.5 part of antioxidant 1010.

Example 13

Example 2 differs from example 1 in that: the conductive film is prepared from the following raw materials in parts by weight: 92.5 parts of PET, 5 parts of conductive particles A in preparation example 13, 2 parts of conductive particles B in preparation example 19, and 0.5 part of antioxidant 1010.

Example 14

Example 14 differs from example 1 in that:

loading the semi-finished film into a quartz mold, wherein one end of the quartz mold is open, the other end of the quartz mold is closed, the quartz mold loaded with the semi-finished film is placed in an environment of 80 ℃, positive electrode plates are parallelly arranged on the opening end faces of the quartz mold, the straight line distance between the opening end faces of the quartz mold and the lower surface of the positive electrode plates is 0.5mm, negative electrode plates are parallelly arranged on the closing end faces of the quartz mold, the straight line distance between the closing end faces of the quartz mold and the lower surface of the negative electrode plates is 18mm, and the electric strength formed between the positive electrode plates and the negative electrode plates is controlled to be 8 x 10 ⁵ N/C, particle migration treatment for 5h, forming a conductive film layer on the surface layer of the semi-finished film, then introducing cooling gas, cooling to 45 ℃ at 12 ℃/min, naturally cooling to normal temperature, obtaining a finished conductive film, treating the finished conductive film by adopting an irradiation crosslinking process, placing the finished conductive film in electron irradiation crosslinking equipment, using cobalt as a radiation source, emitting low-energy electron beams by an electron gun, outputting after the energy is increased to 10MeV by an accelerator, directly irradiating the surface of the finished conductive film under the accelerator, controlling the irradiation dose to be 10Mrad, and controlling the crosslinking treatment time to be 6s, thus obtaining the final product.

Example 15

Example 15 differs from example 1 in that: the conductive film is prepared from the following raw materials in parts by weight: 80 parts of PET, 8 parts of conductive particles A in preparation example 1, 4 parts of conductive particles B in preparation example 19, and 0.5 part of antioxidant 1010.

Example 16

Example 16 differs from example 1 in that: the conductive film is prepared from the following raw materials in parts by weight: 100 parts of PET, 4 parts of conductive particles A in preparation example 1, 2 parts of conductive particles B in preparation example 19, and 0.5 part of antioxidant 1010.

Example 17

Example 17 differs from example 1 in that: and in the fourth step, the particle migration treatment time is 4h.

Example 18

Example 18 differs from example 1 in that: and in the fourth step, the particle migration treatment time is 6h.

Example 19

Example 19 differs from example 1 in that:

loading the semi-finished film into a quartz mold, wherein one end of the quartz mold is open, the other end of the quartz mold is closed, the quartz mold loaded with the semi-finished film is placed in an environment of 165 ℃, positive electrode plates are parallelly arranged on the opening end faces of the quartz mold, the linear distance between the opening end faces of the quartz mold and the lower surface of the positive electrode plates is 0.5mm, negative electrode plates are parallelly arranged on the closing end faces of the quartz mold, the linear distance between the closing end faces of the quartz mold and the lower surface of the negative electrode plates is 18mm, and the electric strength formed between the positive electrode plates and the negative electrode plates is controlled to be 8 x 10 ⁵ N/C, particle migration treatment is carried out for 25min, then the temperature is increased to 166 ℃ in 5min, the temperature is increased to 167 ℃ in 5min after the maintenance of 25min, the temperature is increased to 168 ℃ in 5min after the maintenance of 25min, the temperature is increased to 169 ℃ in 5min, the temperature is increased to 170 ℃ in 5min after the maintenance of 25min, the temperature is increased to 171 ℃ in 5min, the temperature is increased to 172 ℃ in 5min after the maintenance of 25min, the temperature is increased to 173 ℃ in 5min after the maintenance of 25min, the temperature is increased to 174 ℃ in 5min after the maintenance of 25min, the temperature is increased to 175 ℃ in 5min after the maintenance of 1h, a conductive film layer is formed on the surface layer of the semi-finished product film, and cooling gas is introduced, the temperature is reduced to 45 ℃ at 12 ℃ per min, and natural cooling is carried out to normal temperature, so as to obtain the finished product conductive film.

Example 20

Example 20 differs from example 19 in that:

the conductive film is prepared from the following raw materials in parts by weight: 92.5 parts of PET, 5 parts of conductive particles A in preparation example 1, 2 parts of conductive particles B in preparation example 19, 0.5 part of antioxidant 1010, 0.2 part of calcium stearate and 0.1 part of polyglycerin fatty acid ester antifogging agent of Yunnan lotus.

Loading the semi-finished film into a quartz mold, wherein one end of the quartz mold is open, the other end of the quartz mold is closed, the quartz mold loaded with the semi-finished film is placed in an environment of 165 ℃, positive electrode plates are parallelly arranged on the opening end faces of the quartz mold, the linear distance between the opening end faces of the quartz mold and the lower surface of the positive electrode plates is 0.5mm, negative electrode plates are parallelly arranged on the closing end faces of the quartz mold, the linear distance between the closing end faces of the quartz mold and the lower surface of the negative electrode plates is 18mm, and the electric strength formed between the positive electrode plates and the negative electrode plates is controlled to be 8 x 10 ⁵ N/C, particle migration treatment is carried out for 25min, the temperature is increased to 166 ℃ in 5min after maintaining for 25min, the temperature is increased to 167 ℃ in 5min after maintaining for 25min, the temperature is increased to 168 ℃ in 5min after maintaining for 25min, the temperature is increased to 169 ℃ in 5min after maintaining for 25min, the temperature is increased to 170 ℃ in 5min after maintaining for 25min, the temperature is increased to 171 ℃ in 5min after maintaining for 25min, the temperature is increased to 172 ℃ in 5min after maintaining for 25min, the temperature is increased to 173 ℃ in 5min after maintaining for 25min, the temperature is increased to 174 ℃ in 5min after maintaining for 25min, the temperature is increased to 175 ℃ in 5min, the temperature is maintained for 1h, a conductive film layer is formed on the surface layer of a semi-finished product film, cooling gas is introduced, the temperature is reduced to 45 ℃ at 12 ℃ per min, the temperature is naturally cooled to the normal temperature, the finished product conductive film is obtained, the finished product conductive film is subjected to irradiation crosslinking process, the finished product conductive film is placed into electron irradiation crosslinking equipment, cobalt is used as a radiation source, the electron gun emits low-energy electron beams, the energy is increased to 10MeV and then is output, the finished product conductive film is directly irradiated to the radiation surface of the finished conductive film under the accelerator, the irradiation dose is controlled for 10 Ms, and the final crosslinking time is controlled to be 6 m.

Comparative example

Comparative example 1

Comparative example 1 differs from example 1 in that: the conductive film is prepared from the following raw materials in parts by weight: 92.5 parts of PET, 5 parts of conductive particles A in preparation example 14, 2 parts of conductive particles B in preparation example 19, and 0.5 part of antioxidant 1010.

Comparative example 2

Comparative example 2 differs from example 1 in that: the conductive film is prepared from the following raw materials in parts by weight: 92.5 parts of PET, 5 parts of conductive particles A in preparation example 15, 2 parts of conductive particles B in preparation example 19, and 0.5 part of antioxidant 1010.

Comparative example 3

Comparative example 3 differs from example 1 in that: the conductive film is prepared from the following raw materials in parts by weight: 92.5 parts of PET, 5 parts of conductive particles A in preparation example 16, 2 parts of conductive particles B in preparation example 19, and 0.5 part of antioxidant 1010.

Comparative example 4

Comparative example 4 differs from example 1 in that: the conductive film is prepared from the following raw materials in parts by weight: 92.5 parts of PET, 5 parts of conductive particles A in preparation example 17, 2 parts of conductive particles B in preparation example 19, and 0.5 part of antioxidant 1010.

Comparative example 5

Comparative example 5 differs from example 1 in that:

The conductive film is prepared from the following raw materials in parts by weight: 92.5 parts of PET, 5 parts of conductive particles A in preparation example 18, 2 parts of conductive particles B in preparation example 19, and 0.5 part of antioxidant 1010.

Comparative example 6

Comparative example 6 differs from example 1 in that:

the conductive film is prepared from the following raw materials in parts by weight: 100 parts of PET, 3 parts of conductive particles A in preparation example 1, 1 part of conductive particles B in preparation example 19, and 0.5 part of antioxidant 1010.

Comparative example 7

Comparative example 7 differs from example 1 in that:

the conductive film is prepared from the following raw materials in parts by weight: 80 parts of PET, 10 parts of conductive particles A in preparation example 1, 5 parts of conductive particles B in preparation example 19, and 0.8 part of antioxidant 1010.

Comparative example 8

Comparative example 8 differs from example 1 in that:

and in the fourth step, the particle migration treatment time is 3h.

Comparative example 9

Comparative example 9 differs from example 1 in that:

and in the fourth step, the particle migration treatment time is 8h.

Comparative example 10

Comparative example 10 differs from example 1 in that:

the conductive film is prepared from the following raw materials in parts by weight: 92.5 parts of PET, 5 parts of conductive particles A in preparation example 1 and 0.5 part of antioxidant 1010.

Comparative example 11

Comparative example 11 differs from example 1 in that: the conductive film is prepared from the following raw materials in parts by weight: 92.5 parts of PET, 5 parts of conductive particles A in preparation example 1, 2 parts of nano silicon dioxide with the wavelength of 100-200nm and 0.5 part of antioxidant 1010.

Performance test

Detection method/test method

1. Transmittance of the conductive film: the transmittance of the conductive films prepared in examples 1 to 20 and comparative examples 1 to 11 was measured using a UV-NIR spectrophotometer (CARY 5000, agilent, china). Conventional PET substrate was used as a blank 1, ITO conductive film of commercially available PET substrate was used as a blank 2, and SnO of commercially available PET substrate was used as a blank ₂ The conductive film was blank 3, and the ZrO conductive film of the commercially available PET substrate was blank 4.

2. Sheet resistance of conductive film: the sheet resistances of the conductive films prepared in examples 1 to 20 and comparative examples 1 to 11 were measured by a four-probe resistance test system (RTS-9, china).

3. Work function measurement of conductive film: the work functions of the conductive films prepared in examples 1 to 20 and comparative examples 1 to 11 were measured using a prinston Versa SCAN scanning kelvin probe.

Data analysis

Table 1 shows the test parameters of examples 1-20 and comparative examples 1-11

	Transmittance%	Sheet resistance omega/sp	Work function eV
				Blank control group 1	85-88	10 ¹¹ -10 ¹³	-
Blank control group 2	83-86	35-45	3.5-4.2
				Blank control group 3	80-84	40-60	3.6-4.0
Blank control group 4	80-84	40-60	3.2-3.4
				Example 1	80.6	36.8	3.9
Example 2	80.2	37.4	3.9
				Example 3	80.3	36.9	3.9
Example 4	80.5	36.7	4.0
				Example 5	80.1	36.9	3.9
Example 6	80.5	37.3	3.9
				Example 7	80.8	36.9	3.9
Example 8	80.4	36.8	4.1
				Example 9	80.6	36.5	4.2
Example 10	81.3	39.6	4.1
				Example 11	82.1	42.4	4.0
Example 12	80.2	39.1	3.5
				Example 13	80.5	38.5	3.7
Example 14	81.2	34.6	3.7
				Example 15	80.1	31.4	3.7
Example 16	82.3	54.9	3.8
				Example 17	81.2	44.8	3.7
Example 18	80.3	35.6	3.9
				Example 19	80.2	35.2	4.0
Example 20	81.8	35.0	4.0
				Comparative example 1	81.0	36.2	3.7
Comparative example 2	80.4	36.9	3.7
				Comparative example 3	80.2	37.2	3.9
Comparative example 4	79.8	39.4	3.8
				Comparative example 5	80.4	37.5	3.7
Comparative example 6	82.5	379.5	3.6
				Comparative example 7	79.8	35.6	3.9
Comparative example 8	82.5	216.9	3.6
				Comparative example 9	80.2	34.8	4.0
Comparative example 10	81.4	158.5	3.7
				Comparative example 11	81.2	145.9	3.7

As can be seen from the combination of examples 1 to 20 and comparative examples 1 to 11 and the combination of Table 1, the transmittance of the conductive film in examples 1 to 20 was slightly lower than that of the blank 2, but the transmittance in examples 1 to 20 was 80% or more, and the transmittance of the conductive film in example 20, which was optimized and improved, was 81.8%, substantially meets the use requirement of the solar conductive film. In addition, the sheet resistance and work function of the conductive film in examples 1-20 are similar to those of the ITO conductive film of the commercial PET substrate in the blank group 2, so that the performance of the conductive film prepared in the application is comparable to that of the commercial ITO film, and the preparation method is relatively simple, has lower production cost, is convenient for realizing industrialized mass production, and is easy for market popularization.

As can be seen from the combination of examples 1 to 20 and comparative examples 1 to 11 and the combination of table 1, the transmittance and sheet resistance of the conductive films in examples 1 to 4 are not much different from those of the conductive films in comparative examples 1 and 5; however, the work function of the conductive film in examples 1 to 4 is larger than that of the conductive film in comparative example 1 and that of the conductive film in comparative example 5, so that the conductive film produced by doping metal atoms with Ag and Zn has a larger work function, and the prepared solar cell has better output performance. In the application, the mass percentage of Ag in the doped metal atoms is preferably 80-95%.

As can be seen from the combination of examples 1 to 20 and comparative examples 1 to 11 and the combination of table 1, the transmittance and sheet resistance of the conductive films in examples 5 to 7 are not much different from those of the conductive film in comparative example 2; however, the work function of the conductive film in examples 5 to 7 is larger than that of the conductive film in comparative example 2, so that the conductive film produced by combining Ag and Al doped metal atoms has a larger work function, the prepared solar cell has better output performance, and the mass percentage of Ag in the doped metal atoms is preferably 75 to 90 percent.

As can be seen from the combination of examples 1 to 20 and comparative examples 1 to 11 and the combination of table 1, the transmittance and sheet resistance of the conductive films in examples 8 to 9 are not much different from those of the conductive film in comparative example 3; however, the work function of the conductive film in examples 8-9 is larger than that of the conductive film in comparative example 3, so that the conductive film produced by combining Ag, al and Zn doped metal atoms has a larger work function, the prepared solar cell has better output performance, and the mass percentage of Al in the doped metal atoms is 5-10%; the mass percentage of Zn is preferably 10-15%. And the work function of the conductive film in the embodiments 8-9 is larger than that of the conductive film in the embodiments 1-7, so that the conductive film produced by doping metal atoms into the combination of Ag, al and Zn has larger work function, and the prepared solar cell has better output performance.

As can be seen from the combination of examples 1 to 20 and comparative examples 1 to 11 and the combination of table 1, the light transmittance of the conductive films in examples 8, 10 to 11 is not much different from that of the conductive film in comparative example 4; the sheet resistance of the conductive film in examples 8, 10-11 is slightly better than that of the conductive film in comparative example 4, and the work function of the conductive film in examples 8, 10-11 is greater than that of the conductive film in comparative example 4, so that the mass ratio of the doped metal atoms to the inorganic metal-based carrier in the conductive particles A is 1:5-8, and the prepared conductive film has better performance.

As can be seen from the combination of examples 1 to 20 and comparative examples 1 to 11 and the combination of table 1, the transmittance, sheet resistance and work function of the conductive film in example 14 are all better than those of the conductive film in example 1, so that the conductive film produced by the irradiation crosslinking process has an improved transmittance, conductivity and work function, and the irradiation crosslinking process has a positive effect on improving the transmittance, conductivity and work function of the produced conductive film, and can improve the weather resistance and service life of the whole conductive film.

As can be seen in the combination of examples 1 to 20 and comparative examples 1 to 11 and in Table 1, the transmittance of the conductive films in examples 1, 15 to 16 was slightly lower than that of the conductive film in comparative example 6, but the difference was not large. The sheet resistances of the conductive films in examples 1, 15 to 16 are superior to those of the conductive film in comparative example 6, and the work functions of the conductive films in examples 1, 15 to 16 are superior to those of the conductive film in comparative example 6; the transmittance of the conductive films of examples 1, 15-16 was slightly better than that of the conductive film of comparative example 7, and the sheet resistance and work function of the conductive films of examples 1, 15-16 were slightly lower than those of the conductive film of comparative example 7, but the differences were not large, so that the conductive films mainly made of 80-100 parts of PET resin, 4-8 parts of conductive particles A and 2-4 parts of conductive particles B were excellent in combination property.

It can be seen from the combination of examples 1 to 20 and comparative examples 1 to 11 and the combination of table 1 that the transmittance of the conductive films in examples 1 and 17 to 18 is not greatly different from that of the conductive films in comparative examples 8 to 9, but the sheet resistance and work function of the conductive films in examples 1 and 17 to 18 are superior to those of the conductive films in comparative example 8, and the sheet resistance and work function of the conductive films in examples 1 and 17 to 18 are slightly different from those of the conductive films in comparative example 9, so that the particle migration treatment time in the fourth step is preferably controlled to be 4 to 6 hours, the overall conductivity is low due to the excessively short particle migration treatment, the overall production efficiency is low due to the excessively long change of the conductivity due to the excessively long particle migration treatment, and the production cost is high.

As can be seen from the combination of examples 1 to 20 and comparative examples 1 to 11 and the combination of table 1, the transmittance of the conductive film in example 1 is less different from that of the conductive film in comparative examples 10 to 11, and the sheet resistance and work function of the conductive film in example 1 are better than those of the conductive film in comparative examples 10 to 11, therefore, the conductivity and work function of the conductive film in the application can be improved by adding the conductive particles B, and the conductive particles B and the conductive particles a are compounded to form a conductive network with high density easily, so that the overall comprehensive performance is better.

As can be seen from the combination of examples 1 to 20 and comparative examples 1 to 11 and the combination of table 1, the transmittance of the conductive film in example 19 is less different from that of the conductive film in comparative examples 10 to 11, and the sheet resistance and work function of the conductive film in example 19 are superior to those of the conductive film in example 1, therefore, the conductivity and work function of the present application can be improved by adopting the preparation process in example 19, and the conductive particles B and the conductive particles a form a high-density conductive network by adopting the preparation process in example 19, and the overall comprehensive performance is superior.

It can be seen from the combination of examples 1 to 20 and comparative examples 1 to 11 and the combination of table 1 that the conductive film combination properties in example 20 are superior to those in examples 1 to 19 and comparative examples 1 to 11, and thus, example 20 is the best embodiment.

The present embodiment is only for explanation of the present application and is not to be construed as limiting the present application, and modifications to the present embodiment, which may not creatively contribute to the present application as required by those skilled in the art after reading the present specification, are all protected by patent laws within the scope of claims of the present application.

Claims

1. The preparation method of the conductive film is characterized in that the conductive film comprises a flexible substrate and a conductive film layer formed on the surface layer of the flexible substrate, wherein the conductive film layer contains conductive particles A and conductive particles B, and the conductive particles A and the conductive particles B form a conductive network; the particle size of the conductive particles A is controlled to be 10-50nm; the particle size of the conductive particles B is controlled to be 100-250nm; the conductive particles A consist of an inorganic metal-based carrier and doped metal atoms, and the doped metal atoms are fixedly connected to the surface of the inorganic metal-based carrier; the mass ratio of the doped metal atoms to the inorganic metal-based carrier in the conductive particles is 1:5-8; the doped metal atoms are at least one of Ag, zn and Al; the conductive particles B consist of an inorganic silicon-based carrier and nanoscale metal clusters; the nanoscale metal clusters are at least one of silver nanoparticles and copper nanoparticles;

The conductive film is mainly prepared from the following raw materials in parts by weight: 80-100 parts of organic polymer resin, 4-8 parts of conductive particles A and 2-4 parts of conductive particles B; the organic polymer resin is one of PET, PI, TPU;

the inorganic metal-based carrier is tin dioxide with a rutile structure, and when the doped metal atoms are Ag and Zn; the mass percentage of Ag in the doped metal atoms is 80-95%; when the doped metal atoms are Ag and Al; the mass percentage of Ag in the doped metal atoms is 75-90%; when the doped metal atoms are Ag, zn and Al; the mass percentage of Al in the doped metal atoms is 5-10%; the mass percentage of Zn in the doped metal atoms is 10-15%;

the preparation method of the conductive particles A comprises the following steps:

s1, roasting an inorganic metal-based carrier at 400-600 ℃ and 0.8-1.0MPa for 10-15min, cooling, and performing planetary ball milling until the granularity is 10-50nm for later use;

S3, synthesizing a conductive particle precursor by in-situ coprecipitation: adding the precursor of the inorganic metal-based carrier in S1 into the mixed solution in S2 according to the mass ratio of the doped metal atoms to the inorganic metal-based carrier of 1:5-8, reacting for 20-28h at 120-150 ℃, cooling to room temperature after the reaction is finished, centrifugally separating to obtain a solid product, washing the obtained solid product with ethanol and water for at least 3 times respectively, then vacuum drying for 3-5h at 100 ℃, and performing planetary ball milling to obtain conductive particle powder with the granularity of 10-50 nm;

s4, in-situ generating finished conductive particles by a one-step method: placing the conductive particle powder obtained in the step S3 into an atmosphere of 3-10% hydrogen-argon mixture, heating at 350-800 ℃ for 2-4h, cooling to room temperature, and grinding to obtain finished conductive particles;

the preparation method of the conductive film comprises the following steps:

And fourthly, heating the semi-finished film to 3-8 ℃ above Tg to enable molecular chain links in the semi-finished film to freely move, performing particle migration treatment in a uniform electric field to form a conductive film layer on the surface layer of the semi-finished film, performing particle migration treatment for 4-6 hours, and cooling to normal temperature to obtain the finished conductive film.

2. The method for producing a conductive film according to claim 1, wherein: the specific operation of the surface modification treatment of the conductive particles A and the conductive particles B in the step one is that the conductive particles A and the conductive particles B are placed in 5-8g/L of propyl dioleate acyloxy (dioctyl phosphate acyloxy) titanate aqueous solution, ultrasonic treatment is carried out for 30-60min, and the conductive particles A and the conductive particles B are taken out and dried for standby.

3. The method for producing a conductive film according to claim 1, wherein: loading the semi-finished film into a quartz mold, wherein one end of the quartz mold is open, the other end of the quartz mold is closed, the quartz mold loaded with the semi-finished film is placed in an environment of 3-8 ℃ above Tg, positive electrode plates are placed in parallel on the opening end face of the quartz mold, the linear distance between the opening end face of the quartz mold and the lower surface of the positive electrode plates is 0.1-4mm, negative electrode plates are placed in parallel on the closing end face of the quartz mold, the linear distance between the closing end face of the quartz mold and the lower surface of the negative electrode plates is above 15mm, and the electric strength formed between the positive electrode plates and the negative electrode plates is controlled to be 10 ⁴ -10 ⁶ N/C, performing particle migration treatment for 4-6h to form a conductive film layer on the surface layer of the semi-finished film, then introducing cooling gas, cooling to 40-45 ℃ at 10-15 ℃/min, and naturally cooling to normal temperature to obtain the finished conductive film.

4. A method for producing a conductive film according to claim 3, wherein: treating the finished conductive film in the fourth step by adopting an irradiation crosslinking process to obtain the finished conductive film; the irradiation crosslinking process uses cobalt as a radiation source, an electron gun emits low-energy electron beams, the energy is increased to 8-12MeV through an accelerator and then is output, the surface of a finished conductive film under the accelerator is directly irradiated, the irradiation dose is controlled to be 10-15Mrad, and the crosslinking treatment time is controlled to be 6-10s.