Disclosure of Invention
The invention aims to provide a preparation method of a DSA electrode, the electrode prepared by a sol method can enhance the stability and the service life of the electrode, and the degradation rate of toxic and nondegradable organic pollutants is improved.
In order to achieve the purpose, the invention adopts the following technical scheme:
a preparation method of a DSA electrode comprises the following steps:
step a, mixing the following components in a mass ratio of 1: (1-3) weighing Citric Acid (CA) and an alcohol organic solvent, stirring the alcohol organic solvent and the Citric Acid (CA) at the temperature of 60-100 ℃, and heating until the alcohol organic solvent and the Citric Acid (CA) are completely dissolved to obtain a colorless transparent solution;
weighing composite conductive material nano-particle powder and an alcohol organic solvent according to a mass ratio of 1 (13-26), refluxing the composite conductive material nano-particle powder and the alcohol organic solvent for 1-3 h at 80-100 ℃, adding the mixture into the colorless transparent solution, and keeping the mixed solution for 1h at 90-110 ℃ to obtain black sol;
b, coating the sol obtained in the step a on an electrode carrier;
c, drying the coated electrode at 60-120 ℃ for 10-20min, and calcining the dried electrode at 350-550 ℃ for 10-50 min;
and d, repeating the step b and the step c for 5-20 times, and finally calcining for 2 hours at 350-650 ℃ to obtain the DSA electrode.
Furthermore, the composite conductive material nano-particle powder is platinum ruthenium iridium, platinum ruthenium, platinum iridium, ruthenium iridium, antimony doped tin oxide or lead oxide nano-particles.
Further, in step b, the sol is coated on the electrode carrier by using a spin coating, dip-drawing, brush coating or spray coating method.
Further, the alcohol organic solvent is ethanol, methanol, isopropanol or ethylene glycol.
Further, the electrode carrier is a titanium plate, a titanium rod, a special-shaped titanium material, a stainless steel plate, a stainless steel rod or special-shaped stainless steel.
Further, in the step b, before the sol is coated on the electrode carrier, the electrode carrier is subjected to polishing, acid treatment and washing treatment.
Compared with the prior art, the invention has the following beneficial technical effects:
the preparation method of the DSA electrode takes self-made composite material nano particles and citric acid as raw materials, and the electrode prepared by a sol method is an oxide film electrode of the composite material nano particles. The composite conductive material nano-particle powder is adopted to improve the degradation rate of the electrode, is used for electrochemical treatment of actual production wastewater and improves the degradation rate of toxic refractory organic pollutants; the preparation method of the sol improves the stability of the electrode, the noble metal is adopted, the material has good conductivity and is relatively stable, the coating-drying-calcining process is repeated for multiple times to obtain composite material nano particles with certain thickness, the coating solution is tightly combined with the electrode, the coating is not easy to fall off, and the service life of the electrode is effectively prolonged.
Detailed Description
The present invention will be described in further detail with reference to the following examples, which are not intended to limit the invention thereto.
Example 1
a. Stirring and heating 1g of ethylene glycol and 1g of Citric Acid (CA) at 60 ℃ until the ethylene glycol and the Citric Acid (CA) are completely dissolved to obtain a colorless and transparent solution; refluxing 1g of platinum-ruthenium-iridium composite material nanoparticle powder and 13g of ethylene glycol at 80 ℃ for 3h, then adding the mixture into the colorless transparent solution, and keeping the solution at 90 ℃ for 1h to obtain black sol;
b. a titanium electrode is used as a carrier, and grinding, acid treatment and washing are needed before use;
c. coating 13.81ml of the sol in the step a on the surface of the electrode carrier;
d. drying the coated electrode at 100 ℃ for 10min, and calcining the dried electrode at 350 ℃ for 10 min;
e. and c, repeating the step d and the step c for 15 times, and finally calcining for 2h at 450 ℃ to obtain the platinum ruthenium iridium composite material nanoparticle electrode.
The results of the contact angle analysis of the scanning electron microscope and the video image in example 1 are shown in fig. 1 and fig. 2, and it is observed from fig. 1(a) that the electrode surface is rough and has a large surface area, while the particle layer in fig. 1(b) is laminated and has a porous structure, which increases the reaction active area. The contact angle in fig. 2 is 108 degrees, the surface is rough, the hydrophobic effect is good, the reaction is favorably carried out due to less water adsorbed on the surface, and the reaction rate is improved. Fig. 3 is a photograph of a platinum ruthenium iridium composite nanoparticle electrode.
Example 2
a. Stirring and heating at 70 ℃ 2g of isopropanol and 1g of Citric Acid (CA) to completely dissolve to obtain a colorless and transparent solution; refluxing 1g of platinum-ruthenium composite nanoparticle powder and 18g of isopropanol at 90 ℃ for 2h, adding the mixture into the colorless transparent solution, and keeping the solution at 100 ℃ for 1h to obtain black sol;
b. a titanium electrode is used as a carrier, and grinding, acid treatment and washing are needed before use;
c. coating 25.48ml of the sol obtained in the step a on the surface of the electrode carrier;
d. drying the coated electrode at 110 deg.C for 15min, and calcining the dried electrode at 450 deg.C for 30 min;
e. and c, repeating the steps c and d 18 times, and finally calcining at 550 ℃ for 2h to obtain the platinum-ruthenium composite nanoparticle electrode.
Example 3
a. Stirring and heating 3g of ethanol and 1g of Citric Acid (CA) at 85 ℃ until the ethanol and the citric acid are completely dissolved to obtain a colorless and transparent solution; refluxing 1g of ruthenium-iridium composite material nanoparticle powder and 22g of ethanol at 100 ℃ for 3h, then adding the mixture into the colorless transparent solution, and keeping the solution at 110 ℃ for 1h to obtain black sol;
b. a titanium electrode is used as a carrier, and grinding, acid treatment and washing are needed before use;
c. coating 31.85ml of the sol in the step a on the surface of the electrode carrier;
d. drying the coated electrode at 110 ℃ for 10min, and calcining the dried electrode at 550 ℃ for 10 min;
e. and c, repeating the step d and the step c for 19 times, and finally calcining at 650 ℃ for 2h to obtain the ruthenium-iridium composite nanoparticle electrode.
Example 4
a. 1.14g of methanol and 1g of citric acid are stirred and heated at 100 ℃ until completely dissolved, giving a colorless and transparent solution; refluxing 1g of platinum-iridium composite material nano-particle powder and 26g of methanol at 100 ℃ for 1h, then adding the mixture into the colorless transparent solution, and keeping the solution at 110 ℃ for 1h to obtain black sol;
b. a stainless steel electrode is used as a carrier, and grinding, acid treatment and washing are needed before use;
c. coating 34.57ml of the sol in the step a on the surface of the electrode carrier;
d. drying the coated electrode at 120 ℃ for 10min, and calcining the dried electrode at 350 ℃ for 50 min;
e. and c, repeating the steps c and d for 20 times, and finally calcining for 2 hours at 350 ℃ to obtain the platinum-ruthenium composite nanoparticle electrode.
Example 5
a. Stirring and heating 2g of methanol and 1g of citric acid at 100 ℃ until the methanol and the citric acid are completely dissolved to obtain a colorless and transparent solution; refluxing 1g of platinum-iridium composite material nano-particle powder and 26g of methanol at 100 ℃ for 1h, then adding the mixture into the colorless transparent solution, and keeping the solution at 110 ℃ for 1h to obtain black sol;
b. a stainless steel electrode is used as a carrier, and grinding, acid treatment and washing are needed before use;
c. coating 34.57ml of the sol in the step a on the surface of the electrode carrier;
d. drying the coated electrode at 60 deg.C for 20min, and calcining the dried electrode at 350 deg.C for 50 min;
e. and (d) repeating the steps (c) and (d) for 5 times, and finally calcining at 500 ℃ for 2h to obtain the platinum-ruthenium composite nanoparticle electrode.
The composite conductive material nano-particle powder self-made by a laboratory used in the embodiment of the invention is platinum ruthenium iridium, platinum ruthenium, platinum iridium, ruthenium iridium and antimony doped tin oxide or lead oxide nano-particles, and a self-made composite material nano-particle electrode is obtained by a rotary coating, dipping, pulling and brushing method, so that the conclusion is that: the technical effects of the present invention can also be achieved when other conductive carriers are employed.
The electrode carrier is a titanium electrode or a stainless steel electrode, and comprises a titanium plate, a titanium rod, a special-shaped titanium material, a stainless steel plate, a stainless steel rod or a special-shaped stainless steel electrode.
The self-made composite material nanoparticle electrode in the embodiment of the invention is prepared by methods of spin coating, dip coating and brush coating, the methods belong to conventional use methods mastered by technicians in the field, and are widely used for preparing an electro-catalytic electrode, and the technicians in the field can also obtain the self-made composite material nanoparticle electrode with the same performance by other methods or ways, so that the technical effect of the invention is realized.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solutions of the present invention and not for limiting the same, and although the present invention is described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: modifications and equivalents may be made to the embodiments of the invention without departing from the spirit and scope of the invention, which is to be covered by the claims.