Method for in-site synthesis of transparent conductive coating of poly(3,4-ethylenedioxythiophene)/nano silver

Abstract

A method for in-site synthesis of transparent conductive coating of poly(3,4-ethylenedioxythiophene)/nano silver hybrid on transparent substrate is provided. Transparent substrate with oxidant coating containing silver salt is immersed into 3,4-ethylenedioxythiophene (EDOT) solution. The oxidant turns EDOT monomer to poly(3,4-ethylenedioxythiophene) (PEDOT) coating on the transparent substrate; meanwhile, the silver salt itself is reduced to nano silver by the EDOT monomer, resulting in a nano silver-doped PEDOT coating. Thereby, a transparent conductive film made of PEDOT/nano silver coating on transparent substrate is obtained. The transparent conductive film with PEDOT/nano silver coating prepared in the present invention possesses the advantages of high electrical conductivity, optical transparency and environmental stability.

Claims

1. A method for in-site synthesis of transparent conductive coating of poly(3,4-ethylenedioxythiophene)/nano silver hybrid on a transparent substrate, comprising insite synthesis of poly (3,4-ethylenedioxythiophene) and nano silver on the transparent substrate simultaneously; immersing the transparent substrate with an oxidant coating containing silver salt and other oxidants into a 3,4-ethylenedioxythiophene solution, wherein on the transparent substrate, the oxidant coating containing silver salt and other oxidants turns the 3,4-ethylenedioxythiophene to a transparent conductive coating of poly(3,4-ethylenedioxythiophene) by chemical oxidative polymerization; meanwhile, the 3.4-ethylenedioxythiophene turns the silver salt to metal silver by chemical reduction, resulting in the transparent conductive coating of poly(3.4-ethylenedioxythiophene)/nano silver hybrid on the transparent substrate.

2. The method according to claim 1, wherein the silver salt, is silver p-tolueuesulfonate or silver nitrate or a mixture of silver p-toluenesulfonate and silver nitrate: and the molar percent of the silver salt in the oxidant coating is 50-100%; the other oxidants in the oxidant coating contain ferric salt; the content of the oxidant coating on a surface of the transparent substrate is 0.5-10 mmol/m.sup.2.

3. The method according to claim 1, wherein the 3,4-ethylenedioxythiophene solution contains dissolved polyvinylpyrrolidone; the average molecular weight of the polyvinylpyrrolidone is 10000-100000 g/mol; and the mass concentration of the polyvinylpyrrolidone in the 3,4-ethylenedioxythiophene solution is 0.01-2%.

4. The method according to claim 1, wherein the 3,4-ethylenedioxythiophene solution contains 20-400 mmol/C of 3,4-ethylenedioxythiophene; the solvent for the 3,4-ethylenedioxythiophene solution is selected at least one from petroleum ether, hexane, heptane, cyclohexane, benzene, methylbenzene, chloroform, acetonitrile, methanol, ethanol and butanol.

5. The method according to claim 2, wherein the ferric salt is selected at least one from ferric p-toluenesulfonate, ferric trichloride and ferric sulfate; and the molar percent of the p-toluenesulfonate in the oxidant coating is above 40%.

6. The method according to claim 1, wherein the transparent conductive coating of poly(3,4-ethylenedioxythiophene)/nano silver hybrid is synthesized in the 3,4-ethylenedioxythiophene solution at temperature 40-80 C.; the time period of the synthesizing reaction is 0.1-2 hours; just after the synthesizing reaction, the resultant transparent conductive coating of poly(3,4-ethylenedioxythiophene)/nano silver hybrid is immersed in a dilute solution of ferric salt and then cleaned.

7. The method according to claim 1, wherein the transparent substrate is made of glass, poly(methyl methacrylate), polycarbonate, poly(ethylene terephthalate), poly(ethylene naphtholate), cycloolefin polymers, polyimide, cured epoxy resin or organic silicone resin.

8. The method according to claim 1, wherein the transparent substrate is a transparent substrate with a preformed conductive coating of poly(3,4-ethylenedioxythiophene).

9. The method according to claim 1, wherein the transparent substrate is subjected to surface treatment before the oxidant coating is formed; the surface treatment comprises chemical surface modification or vacuum ultraviolet surface modification; the chemical surface modification is hydrolysis or sulfonation; and the vacuum ultraviolet surface modification is photochemical oxidation with 172 nm vacuum ultraviolet.

Description

DETAILED DESCRIPTION OF THE EMBODIMENTS

(1) The present invention is further described below in combination with embodiments. However, the present invention is not limited to the embodiments below.

Embodiment 1

(2) The method comprises the following steps:

(3) Mixing ethanol, isopropanol and acetonitrile in a volume ratio of 3:1:1 to prepare an mixed solvent; dissolving ferric p-toluenesulfonate and silver p-toluenesulfonate at a molar ratio of 1:1 in the mixed solvent to prepare 80 mmol/L of oxidant solution; and adding imidazole into the oxidant solution in a molar ratio of 1:20 of imidazole to p-toluenesulfonate;

(4) Adding 0.3% by weight of acetonitrile into cyclohexane to prepare a mixed cyclohexane solvent; dissolving 0.01% by weight of polyvinylpyrrolidone into the mixed cyclohexane solvent; adding EDOT monomer into the mixed cyclohexane solution and agitating it to prepare a 100 mmol/L of EDOT solution; and

(5) Laying a PET film 2 mm away from the irradiating window of a 172 nm xenon excimer lamp with output of 8 mW/m.sup.2; irradiating the PET film with 172 nm vacuum ultraviolet in atmosphere for 2 minutes and immersing the irradiated PET film into the oxidant solution containing ferric p-toluenesulfonate and silver p-toluenesulfonate for 4 minutes; taking the film out from the oxidant solution and drying it at 45 C. for 2 minutes. PET film with 1.5 mmol/m.sup.2 of oxidant coating was prepared. Suspending the PET film with oxidant coating in the EDOT solution prepared above at 60 C. for 30 minutes; taking the film out and immediately inserting the film in 20 mmol/L of ferric p-toluenesulfonate isopropyl alcohol solution at 60 C. for 2 minutes; washing the film with absolute ethyl alcohol and deionized water, and blowing it with nitrogen stream. Thereby, transparent conductive PET film with PEDOT/nano silver hybrid coating was prepared. The optoelectronic properties of the PET composite film were measured: the light transmittance at 550 nm is 85%, and the sheet resistance is 100 /.

Embodiment 2

(6) The method comprises the following steps:

(7) Mixing ethanol, isopropanol and acetonitrile in a volume ratio of 2:1:2 to prepare a mixed solvent; dissolving ferric p-toluenesulfonate, silver p-toluenesulfonate and silver nitrate at a molar ratio of 1:1:1 into the mixed solvent to prepare 120 mmol/L of oxidant solution containing ferric p-toluenesulfonate, silver p-toluenesulfonate and silver nitrate; and adding imidazole into the oxidant solution in 1:10 molar ratio of imidazole to p-toluenesulfonate and nitrate;

(8) Adding 0.3% by weight of acetonitrile into cyclohexane to prepare a mixed cyclohexane solvent; dissolving 0.01% by weight of polyvinylpyrrolidone in the mixed cyclohexane solvent; and adding EDOT monomer into the mixed cyclohexane solvent and agitating it to prepare 100 mmol/L of EDOT solution; and

(9) Laying a PET film 2 mm away from the irradiating window of a 172 nm xenon excimer lamp with output of 8 mW/m.sup.2; irradiating the PET film with 172 nm xenon excimer lamp in atmosphere for 2 minutes and immersing the irradiated PET film in the oxidant solution containing ferric p-toluenesulfonate, silver p-toluenesulfonate and silver nitrate for 4 minutes; taking the film out, drying it at 45 C. for 2 minutes. PET film with 1.9 mmol/m.sup.2 of oxidant coating was obtained. Suspending the PET film with oxidant coating in the EDOT solution at 60 C. for 40 minutes; taking the film out from the EDOT solution and immediately inserting the film into 20 mmol/L of ferric p-toluenesulfonate isopropyl alcohol solution at 60 C. for 2 minutes; washing the film with absolute ethyl alcohol and deionized water, and blowing it with nitrogen stream. Thereby, PET film with PEDOT/nano silver hybrid coating was prepared. The optoelectronic properties of the PET composite film were measured: the light transmittance at 550 nm is 85%, and the sheet resistance is 80 /.

Embodiment 3

(10) The method comprises the following steps:

(11) Mixing ethanol, isopropanol and acetonitrile in a volume ratio of 3:1:1 to prepare a mixed solvent; dissolving ferric p-toluenesulfonate and silver p-toluenesulfonate at a molar ratio of 1:1 in the mixed alcohol solvent to prepare 100 mmol/L of oxidant solution containing ferric p-toluenesulfonate and silver p-toluenesulfonate; adding imidazole into the oxidant solution in 1:20 molar ratio of imidazole to p-toluenesulfonate;

(12) Mixing cyclohexane and toluene in a volume ratio of 1:1 to prepare a mixed solvent and adding 1% by weight of acetonitrile into the mixed solvent; dissolving 0.02% by weight of polyvinylpyrrolidone in the mixed solvent; and adding EDOT monomer into the mixed solvent and agitating it to prepare 100 mmol/L of EDOT solution; and

(13) Laying a PET film 2 mm away from the irradiating window of a 172 nm xenon excimer lamp with output of 8 mW/m.sup.2; irradiating the PET film with 172 nm xenon excimer lamp in atmosphere for 2 minutes; immersing the irradiated PET film into the oxidant solution containing ferric p-toluenesulfonate and silver p-toluenesulfonate for 4 minutes; taking the film out and drying it at 45 C. for 2 minutes. PET film with 1.8 mmol/m.sup.2 of oxidant coating was obtained. Suspending the PET film with oxidant coating in the EDOT solution at 70 C. for 20 minutes; taking the film out and immediately inserting the film into 20 mmol/L of ferric p-toluenesulfonate isopropyl alcohol solution at 70 C. for 2 minutes, washing the film with absolute ethyl alcohol and deionized water and blowing it with nitrogen stream. Thereby, PET film with PEDOT/nano silver hybrid coating was prepared. The optoelectronic properties of the PET composite film, were measured: the light transmittance at 550 nm is 88%, and the sheet resistance is 80 /.

(14) The embodiments above demonstrated that transparent conductive film comprising transparent conductive coating of PEDOT/nano silver hybrid and transparent substrate can be prepared by immersing PET film with silver salt coating in EDOT solution.

(15) The invention described herein is susceptible to variation, modifications and/or additions other than those specifically described and it is to be understood that the invention includes all such variations, modifications and/or additions which fall within the spirit and scope of the above description.