阅读说明：本技术 一种光电化学防腐保护复合光阳极及其制备方法与应用 (Photoelectrochemistry anti-corrosion protection composite photo-anode and preparation method and application thereof ) 是由 骆静利 刘素云 王学万 向雄志 符显珠 于 2020-05-29 设计创作，主要内容包括：本发明公开一种光电化学防腐保护复合光阳极及其制备方法与应用,所述方法包括步骤：通过电沉积法创造性地将Co(OH)<Sub>2</Sub>和WO<Sub>3</Sub>负载在传统光催化材料TiO<Sub>2</Sub>纳米管薄膜上,制得所述光电化学防腐保护复合光阳极,其中,所述Co(OH)<Sub>2</Sub>能够有效促进光生电荷分离,从而降低复合光阳极的载流子复合率,所述WO<Sub>3</Sub>具有储存电荷的能力从而使得复合光阳极在暗态条件下也能实现光电阴极保护。本发明通过对TiO<Sub>2</Sub>纳米管薄膜进行适当的表面改性处理来提高传统光催化材料的光电性能,实现海洋环境中TiO<Sub>2</Sub>对Q235碳钢等金属的高效光电化学阴极保护,从而高效抑碳钢等金属在海洋环境中的腐蚀。(The invention discloses a photoelectrochemical anti-corrosion protection composite photo-anode and a preparation method and application thereof, wherein the method comprises the following steps: creative Co (OH) by electrodeposition 2 And WO 3 Loaded on the TiO of the traditional photocatalytic material 2 Preparing the photoelectrochemistry anticorrosion protection composite photoanode on a nanotube film, wherein the Co (OH) 2 Can effectively promote the separation of photo-generated charges, thereby reducing the carrier recombination rate of the composite photo-anode, and the WO 3 The compound light anode has the capability of storing charges, so that the compound light anode can realize the photocathode protection under the dark state condition. The invention is through to TiO 2 The nanotube film is subjected to appropriate surface modification treatment to improve the photoelectric property of the traditional photocatalytic material and realize TiO in the marine environment 2 For Q235 carbon steel and other goldBelongs to high-efficiency photoelectrochemical cathodic protection, thereby efficiently inhibiting the corrosion of metals such as carbon steel and the like in the marine environment.)

1. A preparation method of a photoelectrochemistry anticorrosion protection composite photo-anode is characterized by comprising the following steps:

with TiO₂Using a nanotube film as an anode, using a platinum sheet and SCE as a counter electrode and a reference electrode respectively, adding the anode, the counter electrode and the reference electrode into an electrolyte consisting of soluble alkali metal tungstate and hydrogen peroxide, adjusting the electrolyte to be acidic, and enabling the TiO to be acidic by an electrodeposition method₂Nanotube film surface deposition of WO₃To obtain WO₃Modified TiO₂A nanotube film;

subjecting said WO to₃Modified TiO₂Adding the nanotube film into cobalt salt solution, deionized water, strong alkali solution and deionized water in sequence, circularly depositing for several times, and depositing in the WO₃Modified TiO₂Deposition of Co (OH) on nanotube films₂And (4) granulating to obtain the photoelectrochemistry anticorrosion protection composite photo-anode.

2. The method for preparing the photoelectrochemical anti-corrosion protection composite photoanode as claimed in claim 1, wherein a constant voltage of (-0.7V) - (-0.1V) is applied to the anode and maintained for 1-5min to make the TiO remain₂Nanotube film surface deposition of WO₃。

3. The preparation method of the photoelectrochemical anti-corrosion protection composite photo-anode according to claim 1, wherein a molar ratio of the soluble alkali metal tungstate to the hydrogen peroxide in the electrolyte is 1:3-3: 1.

4. The method for preparing the photoelectrochemical anti-corrosion protection composite photoanode as claimed in claim 1, wherein the TiO is selected from the group consisting of TiO, and the method is further characterized in that the method comprises the step of preparing the photoelectrochemical anti-corrosion protection composite photoa₂The nanotube film is subjected to heat treatment at 400-600 ℃.

5. The method for preparing the photoelectrochemical anti-corrosion protective composite photoanode as claimed in claim 1, wherein the pH of the electrolyte is 1 to 3.

6. The method for preparing the photoelectrochemical anti-corrosion protection composite photoanode as claimed in claim 1, wherein the cobalt salt solution is CoCl₂Solution, CoCO₃Solutions or CoSO₄One of the solutions.

7. The method for preparing the photoelectrochemical anti-corrosion protective composite photoanode as claimed in claim 1, wherein the strong alkaline solution is a sodium hydroxide solution or a potassium hydroxide solution.

8. The method for preparing the photoelectrochemical anti-corrosion protection composite photoanode as claimed in claim 1, wherein the WO is applied to the preparation of the photoelectrochemical anti-corrosion protection composite photoanode₃Modified TiO₂Adding the nanotube film into cobalt salt solution, deionized water, strong alkali solution and deionized water in sequence, and performing cyclic deposition for 3-10 times, wherein the deposition time is 4-8s each time₃Modified TiO₂Deposition of Co (OH) on nanotube films₂And (4) granulating to obtain the photoelectrochemistry anticorrosion protection composite photo-anode.

9. A photoelectrochemical anti-corrosion protection composite photo-anode is characterized by being prepared by the preparation method of the photoelectrochemical anti-corrosion protection composite photo-anode according to any one of claims 1 to 8.

10. The application of the photoelectrochemistry anticorrosion protection composite photo-anode is characterized in that the photoelectrochemistry anticorrosion protection composite photo-anode disclosed by claim 9 is used for metal anticorrosion.

Technical Field

The invention relates to the field of metal corrosion prevention, in particular to a photoelectrochemistry corrosion prevention protection composite photo-anode and a preparation method and application thereof.

Background

The problem of corrosion of metals in marine environments is very severe, with countless economic losses and safety problems due to corrosion of materials every year. Sacrificial anode protection has evolved as an inexpensive, scalable means of protection that produces a protective current density that meets the protection requirements of most metallic materials. The photoelectrochemical cathodic protection of the photocatalytic material is a metal protection mode with great potential, electron transition can be generated under illumination, then electrons are transferred to the surface of the metal material to inhibit the corrosion of the metal, and the characteristics of no reaction consumption and environmental friendliness of the photocatalytic material in the illumination protection process have attracted extensive attention of researchers.

However, the high carrier recombination rate and limited visible light absorption of a single photocatalytic material are always main problems which hinder the application and development of the material, and the existing photocatalytic material loses the protection function under the condition of no light and is not beneficial to uninterrupted continuous protection of metal.

Accordingly, the prior art is yet to be improved and developed.

Disclosure of Invention

In view of the defects of the prior art, the invention aims to provide a photoelectrochemical anti-corrosion protection composite photo-anode and a preparation method and application thereof, and aims to solve the problem that the application and development of a photocatalytic material in a practical environment are limited due to the defects that the existing photocatalytic material is high in carrier recombination rate, limited in visible light absorption, capable of only acting under light and the like.

The technical scheme of the invention is as follows:

a preparation method of a photoelectrochemical anti-corrosion protection composite photo-anode comprises the following steps:

with TiO₂The nanotube film is used as an anode, a platinum sheet and SCE are respectively used as a counter electrode and a reference electrode, and the anode, the counter electrode and the reference electrode are added into a group consisting of soluble alkali metal tungstate and hydrogen peroxideIn the resulting electrolyte, and adjusting the electrolyte to acidity, the TiO is electrodeposited₂Nanotube film surface deposition of WO₃To obtain WO₃Modified TiO₂A nanotube film;

subjecting said WO to₃Modified TiO₂Adding the nanotube film into cobalt salt solution, deionized water, strong alkali solution and deionized water in sequence, circularly depositing for several times, and depositing in the WO₃Modified TiO₂Deposition of Co (OH) on nanotube films₂And (4) granulating to obtain the photoelectrochemistry anticorrosion protection composite photo-anode.

The preparation method of the photoelectrochemical anti-corrosion protection composite photo-anode comprises the steps of applying a constant voltage of (-0.7V) - (-0.1V) to the anode and keeping the constant voltage for 1-5min to enable the TiO to be in contact with the anode₂Nanotube film surface deposition of WO₃。

The preparation method of the photoelectrochemistry anticorrosion protection composite photo-anode comprises the step of preparing an electrolyte, wherein the molar ratio of soluble alkali metal tungstate to hydrogen peroxide in the electrolyte is 1:3-3: 1.

The preparation method of the photoelectrochemistry anticorrosion protection composite photoanode comprises the following steps of₂The nanotube film is subjected to heat treatment at 400-600 ℃.

The preparation method of the photoelectrochemistry anticorrosion protection composite photo-anode comprises the step of preparing an electrolyte, wherein the pH value of the electrolyte is 1-3.

The preparation method of the photoelectrochemical anti-corrosion protection composite photo-anode comprises the step of preparing a cobalt salt solution by using CoCl₂Solution, CoCO₃Solutions or CoSO₄One of the solutions.

The preparation method of the photoelectrochemistry anticorrosion protection composite photo-anode comprises the step of preparing a composite photo-anode by using a solution of strong base, wherein the solution of strong base is a sodium hydroxide solution or a potassium hydroxide solution.

The preparation method of the photoelectrochemical anti-corrosion protection composite photoanode comprises the following steps of₃Modified TiO₂Adding the nanotube film into cobalt salt solution, deionized water, strong alkali solution and deionized water in sequence, and performing cyclic deposition for 3-10 times, wherein the deposition time is 4-8s each time₃Modified TiO₂Nano meterDeposition of Co (OH) on the surface of tube film₂And (4) granulating to obtain the photoelectrochemistry anticorrosion protection composite photo-anode.

The invention discloses a photoelectrochemistry anticorrosion protection composite photo-anode, which is prepared by adopting the preparation method of the photoelectrochemistry anticorrosion protection composite photo-anode.

The invention discloses application of a photoelectrochemistry anticorrosion protection composite photo-anode, wherein the photoelectrochemistry anticorrosion protection composite photo-anode is used for metal anticorrosion.

Has the advantages that: the invention provides a preparation method of a photoelectrochemical anti-corrosion protection composite photo-anode, which creatively uses Co (OH)₂And WO₃Loaded on the TiO of the traditional photocatalytic material₂On nanotube films, the Co (OH)₂Can effectively promote the separation of photo-generated charges, thereby reducing the carrier recombination rate of the composite photo-anode, and the WO₃The composite photo-anode has the capability of storing charges, so that the composite photo-anode can realize the protection of the photo-cathode under the dark state condition₂The nanotube film is subjected to appropriate surface modification treatment to improve the photoelectric property of the traditional photocatalytic material and realize TiO in the marine environment₂The high-efficiency photoelectrochemistry cathode protection is carried out on metals such as Q235 carbon steel, so that the corrosion of the metals such as the carbon steel in the marine environment is effectively inhibited.

Drawings

Fig. 1 is a flow chart of a preferred embodiment of the preparation method of the photoelectrochemical anticorrosion protection composite photo-anode of the present invention.

Fig. 2 is an SEM electron microscope image of the photoelectrochemical anticorrosion protection composite photo-anode prepared in example 1 of the present invention.

FIG. 3 shows Co (OH) prepared in example 1 of the present invention₂/WO₃/TiO₂And (3) connecting the photo-anode with the aluminum alloy, placing the photo-anode in a 3.5% NaCl solution, wherein one side of the photo-anode adopts 12h illumination/12 h dark state, and a corrosion morphology graph of the aluminum alloy is obtained after 15 days.

FIG. 4 shows an unmodified TiO compound in example 2 of the present invention₂Connecting the photo-anode with the aluminum alloy, placing the photo-anode in 3.5% NaCl solution, adopting 12h illumination/12 h dark state on one side of the photo-anode, and observing the corrosion of the aluminum alloy after 15 daysAnd (6) topography.

FIG. 5 shows WO in example 3 of the present invention₃Modified TiO₂And (3) connecting the photo-anode with the aluminum alloy, placing the photo-anode in a 3.5% NaCl solution, adopting 12h illumination/12 h dark state on one side of the photo-anode, and observing a corrosion morphology graph of the aluminum alloy after 15 days.

Detailed Description

The invention provides a photoelectrochemical anti-corrosion protection composite photo-anode and a preparation method and application thereof, and the invention is further described in detail below in order to make the purpose, technical scheme and effect of the invention clearer and clearer. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Due to the defects of high carrier recombination rate, limited visible light absorption, capability of acting only under illumination and the like of the traditional photocatalytic material, the application and development of the photocatalytic material in the actual environment are limited, and the corrosion of metal in the marine environment cannot be effectively prevented.

Based on the problems in the prior art, the invention provides a preparation method of a photoelectrochemical anticorrosion protection composite photo-anode, which comprises the following steps of:

s10, in TiO₂Using a nanotube film as an anode, using a platinum sheet and SCE as a counter electrode and a reference electrode respectively, adding the anode, the counter electrode and the reference electrode into an electrolyte consisting of soluble alkali metal tungstate and hydrogen peroxide, adjusting the electrolyte to be acidic, and enabling the TiO to be acidic by an electrodeposition method₂Nanotube film surface deposition of WO₃To obtain WO₃Modified TiO₂A nanotube film;

s20, application of the WO₃Modified TiO₂Adding the nanotube film into cobalt salt solution, deionized water, strong alkali solution and deionized water in sequence, circularly depositing for several times, and depositing in the WO₃Modified TiO₂Deposition of Co (OH) on nanotube films₂And (4) granulating to obtain the photoelectrochemistry anticorrosion protection composite photo-anode.

In the embodiment, TiO with good chemical stability and wide application in the field of photocatalysis is selected₂The material is used as a composite photo-anode made of TiO₂From the research angle of the preparation process, the surface of the titanium dioxide is properly modified, and the attempt is made to improve the TiO from the source₂The charge transfer capability of the material, the recombination rate of a current carrier are controlled, the continuity of the photocatalytic material to the cathode protection is improved through the recombination with the energy storage material, and the preparation of the light sacrificial anode material in the marine environment is realized. Specifically, this example was made by inventively combining Co (OH)₂And WO₃Loaded on the TiO of the traditional photocatalytic material₂On nanotube films, the Co (OH)₂Can effectively promote the separation of photo-generated charges, thereby reducing the carrier recombination rate of the composite photo-anode, and the WO₃The composite photo-anode has the capability of storing charges, so that the composite photo-anode can realize the protection of the photo-cathode under the dark state condition₂The nanotube film is subjected to appropriate surface modification treatment to improve the photoelectric property of the traditional photocatalytic material and realize TiO in the marine environment₂The high-efficiency photoelectrochemistry cathode protection is carried out on metals such as Q235 carbon steel, so that the corrosion of the metals such as the carbon steel in the marine environment is effectively inhibited.

In some embodiments, the TiO₂The nanotube film can be prepared by anodic oxidation. Specifically, the Ti sheet is taken out of the absolute ethyl alcohol solution, dried and connected to the anode of a direct current power supply, the platinum sheet is taken as the cathode, a potential is applied to the electrolyte for anodic oxidation, and the material is further subjected to heat treatment by using a muffle furnace at the temperature of 400-600 ℃ to obtain TiO₂Photo-anode materials, i.e. said TiO₂A nanotube film. In this embodiment, if the heat treatment temperature is lower than 400 ℃ or higher than 600 ℃, the TiO formation will be caused₂The nanotubes are distorted and sufficient photocatalytic properties cannot be achieved.

In some embodiments, the compound is TiO₂The method comprises the steps of taking a nanotube film as an anode, taking a platinum sheet and SCE (calomel) as a counter electrode and a reference electrode respectively, adding the anode, the counter electrode and the reference electrode into an electrolyte consisting of soluble alkali metal tungstate and hydrogen peroxide, adjusting the pH value of the electrolyte to be 1-3 by adopting concentrated nitric acid, and applying an electrodeposition method on the anodeAdding a constant voltage of (-0.7V) - (-0.1V) and holding for 1-5min to make the TiO₂Nanotube film surface deposition of WO₃To obtain WO₃Modified TiO₂A nanotube film. Due to WO₃Has the ability to store charge, and therefore in the TiO₂Nanotube film surface deposition of WO₃And then, the finally prepared photoelectrochemistry anticorrosion protection composite light anode can realize the protection of a photocathode under a dark condition.

Specifically, in this example, electrodeposition was used to deposit on TiO₂Nanotube film surface deposition of WO₃The principle of the method is that tungsten peroxide salt is used as a precursor to generate oxidation-reduction reaction, and the reaction is as follows:

2WO₄ ^2-+4H₂O₂→W₂O₁₁ ^2-+3H₂O+2OH^-

W₂O₁₁ ^2-+(2+x)H⁺+xe^-→2WO₃+(2+x)/2H₂O+(8-x)/2O₂。

this example is for TiO₂The applied voltage of the nanotube film is (-0.7V) - (-0.1V), and the potential difference can cause TiO₂WO deposited on the surface of the electrode₃The absorption spectra are different; to realize WO₃In TiO₂Uniform deposition of nanotube film surface, soluble alkali metal tungstate in the electrolyte and the H₂O₂In a molar ratio of 1:3 to 3:1, and the concentration of the soluble alkali metal tungstate is 1 to 10 mmol/L. By way of example, the soluble alkali metal tungstate may be Na₂WO₄·H₂O。

In this example, since the reduction reaction of tungstate ions is performed under acidic conditions, concentrated nitric acid is used to adjust the pH of the electrolyte to 1 to 3.

This example uses potentiostatic method on TiO₂Nanotube film surface deposition of WO₃The time of (1) to (5) min, shorter deposition time, WO₃Not yet completely filling the voids, long deposition times, WO₃Will block TiO₂Pore structure of nanotube film and even piling up into clustersAnd both the polymers can influence the absorption characteristic of the final photoelectrochemical anticorrosion protection composite photo-anode.

In some embodiments, the WO is₃Modified TiO₂Adding the nanotube film into cobalt salt solution, deionized water, strong alkali solution and deionized water in sequence, and performing cyclic deposition for 3-10 times, wherein the deposition time is 4-8s each time₃Modified TiO₂Deposition of Co (OH) on nanotube films₂And (4) granulating to obtain the photoelectrochemistry anticorrosion protection composite photo-anode. Due to Co (OH)₂The particles are capable of facilitating photogenerated charge separation and are therefore described in said WO₃Modified TiO₂Deposition of Co (OH) on nanotube films₂The particles can effectively reduce the carrier recombination rate of the composite photo-anode, so that the finally prepared photoelectrochemistry anticorrosion protection composite photo-anode can effectively realize photoelectrochemistry cathodic protection on metal.

In some embodiments, the cobalt salt solution is CoCl₂Solution, CoCO₃Solutions or CoSO₄One of the solutions, but not limited thereto.

In some embodiments, the strong alkaline solution is a sodium hydroxide solution or a potassium hydroxide solution, but is not limited thereto.

In some embodiments, the invention further provides a photoelectrochemical anticorrosion protection composite photo-anode which is prepared by the preparation method of the photoelectrochemical anticorrosion protection composite photo-anode.

In some embodiments, the invention further provides an application of the photoelectrochemistry anticorrosion protection composite photo-anode, and the photoelectrochemistry anticorrosion protection composite photo-anode provided by the invention is used for metal anticorrosion.

The preparation method and the performance of the photoelectrochemical anti-corrosion protection composite photo-anode provided by the invention are further explained by the following specific examples: