A titanium-based tin-antimony-nickel metal coating electrode, its preparation method and application

Abstract

The invention discloses a titanium-based tin-antimony-nickel metal coating electrode and a preparation method and application thereof. The specific preparation process is as follows: pretreating a titanium sheet, sequentially adding a tin-containing compound, a nickel-containing compound and a compound of other types of metal M and a surfactant to isopropanol, ultrasonically mixing them to form a solution A, adding an antimony-containing compound to isopropanol, adding concentrated hydrochloric acid to dissolve it, ultrasonically mixing them to form a solution B, mixing solution A and solution B to form a precursor liquid C, and evenly brushing the precursor liquid C on both sides of the titanium sheet, drying it to form a film on the titanium sheet, heating it in a muffle furnace after drying, thermally decomposing the film, repeating the coating, drying and heating process 5-15 times, and the metal M is Ce, Gd, Fe, Co, La, Cu, Pd or Mn. The electrode prepared by the present invention shows higher Faraday efficiency and stability in the process of electrocatalytic preparation of ozone, and the electrode material cost is low, the reaction conditions are mild, and the energy consumption is low.

Description

Technical Field

[0001] The present invention belongs to the technical field of electrocatalysis, and particularly relates to a titanium-based tin-antimony-nickel metal-coated electrode, a preparation method thereof, and an application thereof. Background Art

[0002] Ozone is a light blue gas with a special odor and strong oxidizing properties, and is now widely used in aspects such as fruit and vegetable disinfection, household laundry, and treatment of industrial wastewater. At present, the main industrial methods for preparing ozone are ultraviolet radiation method, dielectric barrier discharge method, and electrolysis method. Among them, the DSA electrode plate has great advantages in electrolytic production of ozone. The anode size of the DSA electrode plate is stable, and the distance between the electrodes does not change during electrolysis; it has strong corrosion resistance and can work in many electrolytes with strong corrosion and special requirements; the base metal titanium can be reused. The titanium anode was first used in chlor-alkali production and has now been widely used in industries such as chemical engineering, environmental protection, water electrolysis, water treatment, electro-metallurgy, electroplating, etc.

[0003] However, there are some problems with traditional DSA electrode plates. For example, the PbO2 electrode will experience peeling of the electrode surface coating and enter the water body, releasing Pb 4+ into the electrolyte and the product, causing pollution; the traditional Ti / SnO2-Sb-Ni electrode can generate a large overpotential and can generate a large amount of hydroxyl radicals during electrolytic production of ozone, so it has good electrocatalytic ability. However, it also faces problems such as short lifespan, poor stability, poor corrosion resistance, and difficulty in withstanding high current density. Summary of the Invention

[0004] In order to overcome the deficiencies of traditional Ti / SnO2-Sb-Ni electrodes and improve the service life of the electrodes and more stably generate ozone during electrolysis. The purpose of the present invention is to provide a titanium-based tin-antimony-nickel metal-coated electrode, a preparation method thereof, and an application thereof. By adding another metal element M (M = Ce, Gd, Fe, Co, La, Cu, Pd, Mn) to the traditional Ti / SnO2-Sb-Ni electrode, the bonding force between the coating and the substrate material is enhanced, enabling it to continuously generate high-concentration ozone gas during electrolysis.

[0005] The specific technical solutions are as follows:

[0006] A preparation method of a titanium-based tin-antimony-nickel metal-coated electrode, comprising the following steps:

[0007] 1) Titanium sheet pretreatment: Cut the porous titanium plate into titanium sheets, polish the titanium sheets until the surface has a silvery white metallic luster, immerse the polished titanium sheets in a sodium hydroxide solution, heat them in an oil bath to remove surface oil stains, and then wash the titanium sheets with deionized water. After washing, immerse the titanium sheets in an oxalic acid solution and heat them in an oil bath. After heating, take them out and wash them with ultrapure water, and dry them in a vacuum drying oven for 1-4 hours.

[0008] 2) Preparation of precursor solution: Add tin-containing compounds, nickel-containing compounds, compounds of other types of metal M and surfactants to isopropanol in sequence, and mix them thoroughly by ultrasonication to form solution A; add antimony-containing compounds to isopropanol, and add concentrated hydrochloric acid to dissolve them; mix them thoroughly by ultrasonication to form solution B; and mix solution A and solution B to form precursor solution C;

[0009] 3) Heat treatment: The precursor solution C prepared in step 2) is evenly applied to both sides of the titanium sheet treated in step 1), and dried in an oven to form a film on the titanium sheet. After drying, the film is heated in a muffle furnace to thermally decompose the film, and this step is repeated 5-15 times.

[0010] Furthermore, in step 1), the mass concentration of the sodium hydroxide solution is 5-20%, the mass concentration of the oxalic acid solution is 5-20%, the oil bath temperature is 60-100° C., and the oil bath heating time is 1-3 h.

[0011] Furthermore, the tin-containing compound in step 2) is tin tetrachloride pentahydrate, stannous chloride or stannous sulfate, the nickel-containing compound is nickel dichloride hexahydrate or nickel bromide, the antimony-containing compound is antimony trioxide or antimony pentoxide, other types of metal compounds are nitrates or chlorides of Ce, Gd, Fe, Co, La, Cu, Pd or Mn, and the surfactant is PVP, CTAB, P123, F127 or PEG.

[0012] Furthermore, in step 2), the molar ratio of Sn, Sb, Ni and metal M is 10-90:1-15:1-20:1-10.

[0013] Furthermore, in step 2), the concentration of the tin compound in the precursor solution C is 100 g / L~320 g / L, the concentration of the nickel compound is 3 g / L~10 g / L, the concentration of the antimony compound is 3 g / L~10 g / L, the concentration of the metal M compound is 2 g / L~10 g / L, and the concentration of the surfactant is 2 g / L~20 g / L.

[0014] Furthermore, in step 3), the oven drying temperature is 60-150° C., the drying time is 5-20 min, and the muffle furnace heating temperature is 500-800° C., the time is 5-20 min.

[0015] Further, in step 2), the molar ratio of concentrated hydrochloric acid to the antimony-containing compound is 2-10:1.

[0016] Further, in step 1), the titanium sheet is polished successively with 10-100 mesh coarse sandpaper and 100-600 mesh fine sandpaper.

[0017] A titanium-based tin-antimony-nickel metal-coated electrode prepared by the above preparation method.

[0018] An application of a titanium-based tin-antimony-nickel metal-coated electrode in electrocatalytic decomposition of water to produce ozone, including the following steps: controlling the current by a constant current instrument, reacting in a single electrolytic cell, using 0.5 M sulfuric acid as the electrolyte, the titanium-based tin-antimony-nickel metal-coated electrode as the working electrode, a platinum sheet as the counter electrode, setting the reaction current to 1 A, and performing electrocatalytic production of ozone.

[0019] The beneficial effects of the present invention are as follows:

[0020] 1) The titanium-based tin-antimony-nickel metal-coated electrode of the present invention uses various non-precious metal salts as raw materials. After physically mixing various metal salts and surfactants with a solvent to form a precursor solution, the titanium sheet is dried in an oven and heated in a muffle furnace by an impregnation method, and repeated several times to obtain the final required electrode, and the preparation method is simple;

[0021] 2) The titanium-based tin-antimony-nickel metal-coated electrode of the present invention has the characteristics of diverse morphologies and more exposed active sites. During the preparation process of the titanium-based tin-antimony-nickel metal-coated electrode, adding different metals M will cause different morphologies to form on the electrode surface, and the surfactant also provides the necessary conditions for the formation of the morphology, improving the reaction catalytic activity and stability of electrolyzing water to produce ozone;

[0022] 3) Compared with the problems of higher working voltage and shorter electrode life of traditional commercial titanium-based tin-antimony-coated electrodes, the electrode prepared by the present invention is used for the preparation of electrolyzed water ozone, and has the advantages of high electrocatalytic activity, long life and good stability. Description of the Drawings

[0023] Figure 1 It is a transmission electron microscope observation image of the titanium-based tin-antimony-nickel-cerium coated electrode obtained in Example 1 at 30 μm;

[0024] Figure 2 It is a transmission electron microscope observation image of the titanium-based tin-antimony-nickel-cerium coated electrode obtained in Example 1 at 10 μm;

[0025] Figure 3 It is a transmission electron microscope observation image of the titanium-based tin-antimony-nickel-cerium coated electrode obtained in Example 1 at 5 μm;

[0026] Figure 4Transmission electron microscope observation image of the titanium-based tin-antimony-nickel-gadolinium coating electrode obtained in Example 2 at 10 μm;

[0027] Figure 5 Transmission electron microscope observation image of the titanium-based tin-antimony-nickel-gadolinium coating electrode obtained in Example 2 at 5 μm;

[0028] Figure 6 Transmission electron microscope observation image of the titanium-based tin-antimony-nickel-iron coating electrode obtained in Example 3 at 10 μm;

[0029] Figure 7 Transmission electron microscope observation image of the titanium-based tin-antimony-nickel-iron coating electrode obtained in Example 3 at 5 μm;

[0030] Figure 8 Transmission electron microscope observation image of the titanium-based tin-antimony-nickel-cobalt coating electrode obtained in Example 4 at 20 μm;

[0031] Figure 9 Transmission electron microscope observation image of the titanium-based tin-antimony-nickel-cobalt coating electrode obtained in Example 4 at 10 μm;

[0032] Figure 10 Transmission electron microscope observation image of the titanium-based tin-antimony-nickel-lanthanum coating electrode obtained in Example 5 at 20 μm;

[0033] Figure 11 Transmission electron microscope observation image of the titanium-based tin-antimony-nickel-lanthanum coating electrode obtained in Example 5 at 8 μm;

[0034] Figure 12 Real-time detection data comparison chart of the ozone concentration generated when the titanium-based tin-antimony-nickel metal coating electrodes prepared in Examples 1-8 are used for electrocatalytic ozone preparation. Detailed implementation mode

[0035] The present invention will be further described below in conjunction with specific embodiments, but the protection scope of the present invention is not limited thereto.

[0036] Example 1

[0037] Prepare a Ti / SnO2-Sb-Ni-Ce electrode, including the following steps:

[0038] (1)Pretreatment of titanium sheets: Cut the titanium plates into a plurality of titanium sheets of the same size of 20 mm × 20 mm; first use a 60-mesh coarse sandpaper wheel, and then use a 320-mesh fine sandpaper wheel to mechanically polish the surface of the titanium substrate, so that the surface of the electrode shows a silver-white metallic luster. Then, put the titanium sheets into a sodium hydroxide solution with a mass concentration of 15%, and heat them in an oil bath at 80 °C for 1 h to remove the surface oil stains. After washing with deionized water, soak the above-mentioned titanium substrate in an oxalic acid solution with a mass concentration of 10%, and heat it in an oil bath at 80 °C for 2 h. After the surface of the titanium substrate shows a pitted state, take it out, rinse it thoroughly with ultrapure water, and put it in a vacuum drying oven for drying.

[0039] (2)Preparation of the precursor solution: Add 4.59 g of SnCl4·5H2O, 123 mg of NiCl2·6H2O, 67.5 mg of CeCl5·7H2O, and 250 mg of F127 to 12.5 ml of isopropanol in sequence, and ultrasonically mix for 30 min to make them fully mixed, denoted as solution A. Add 252.4 mg of Sb2O3 to 0.14 ml of isopropanol, transfer 1.4 ml of concentrated hydrochloric acid to dissolve it, and ultrasonically mix for 30 min to make it fully mixed, denoted as solution B. Directly mix solution A and B to obtain the required precursor solution C.

[0040] (3)Heat treatment: Uniformly apply the precursor solution C obtained in step (2) on the titanium sheets, dry it in an oven at 100 °C for 10 min to form a film on the titanium sheets; after drying, heat it in a muffle furnace at 550 °C for 10 min to thermally decompose the film, so that SnCl4·5H2O, NiCl2·6H2O, CeCl5·7H2O, and SbCl3 decompose and oxidize, and repeat this step 12 times.

[0041] The schematic diagram of the transmission electron microscope of the titanium-based tin-antimony-nickel-cerium coating electrode obtained in Example 1 at 30 μm and the schematic diagrams of the scanning electron microscope at 10 μm and 5 μm are respectively as Figure 1 、 Figure 2 and Figure 3 shown. The titanium-based tin-antimony-nickel-cerium coating electrode has a "fish scale" morphology, can well cover the titanium matrix, and improve the electrode stability.

[0042] The titanium-based tin-antimony-nickel-cerium coating electrode of Example 1 is used for the reaction of electrolyzing water to prepare ozone:

[0043] The voltage and current are controlled by a constant current instrument, and the reaction is carried out in a single cell. Ti / Ce-Ni-SnO2-Sb2O5 is used as the working electrode, a platinum sheet is used as the counter electrode, the electrolyte is a 0.5 M H2SO4 solution, and one end of the single electrolytic cell is connected to an ozone detector to detect the generation of ozone in real time. When electrocatalytically producing ozone, the current is controlled at 1 A, the cell voltage is controlled between 3 - 6 V, and the reaction time is 10 hours. As the reaction proceeds, the real-time detection diagram of the ozone concentration obtained by the electrocatalytic reaction is asFigure 12 as shown. From Figure 12 it can be seen above that as the reaction proceeds, the ozone concentration increases rapidly. The ozone concentration can reach 200 ppm within 1 minute of reaction time, and can stabilize at 100 ppm after 2 hours of reaction.

[0044] To verify the catalytic stability of the titanium-based tin-antimony-nickel-cerium coated electrode prepared in Example 1, the working electrode after the above reaction once was placed for 24 hours, and a repeated electrocatalytic ozone preparation reaction experiment was carried out (the working electrode was placed for one day each time after use, and then used for the next time). In the first experiment of the repeated use reaction of the working electrode, the ozone concentration could stabilize at 100 ppm after 2 hours of reaction. In the second experiment of the repeated use reaction of the working electrode, the ozone concentration could stabilize at 95 ppm after 2.5 hours of reaction. In the third experiment of the repeated use reaction of the working electrode, the ozone concentration could stabilize at 90 ppm after 3 hours of reaction. It can be seen that during the repeated use process of the working electrode, the electrocatalytic effect is basically not weakened, indicating that the titanium-based tin-antimony-nickel-cerium coated electrode prepared in Example 1 has good stability.

[0045] Example 2

[0046] Prepare a Ti / SnO2-Sb-Ni-Gd electrode, including the following steps:

[0047] (1) Pretreatment of titanium sheet: Cut the titanium plate into a plurality of titanium sheets of the same size of 20 mm×20 mm; first use a 10-mesh coarse sandpaper wheel, and then use a 100-mesh fine sandpaper wheel to mechanically polish the surface of the titanium substrate so that the electrode surface shows a silver-white metallic luster. Then put the titanium sheet into a sodium hydroxide solution with a mass concentration of 5%, heat it in an oil bath at 60 °C for 1 h to remove the surface oil stain, wash it with deionized water, and then soak the above titanium substrate in an oxalic acid solution with a mass concentration of 5%, heat it in an oil bath at 60 °C for 1 h, take it out after the surface of the titanium substrate shows a pitted state, rinse it with ultrapure water, and put it into a vacuum drying oven for drying.

[0048] (2) Preparation of the precursor solution: Add 2.5 g of SnCl2, 75 mg of NiBr2, 75 mg of Gd(NO3)3·xH2O and 50 mg of PVP, add 12.5 ml of isopropanol as a solvent, and ultrasonically mix it for 30 min to make it fully mixed, denoted as solution A. Add 75 mg of Sb2O3, transfer 0.21 ml of concentrated hydrochloric acid to dissolve it, add 12.5 ml of isopropanol as a solvent, and ultrasonically mix it for 30 min to make it fully mixed, denoted as solution B. Directly mix solution A and B to obtain the required precursor solution C.

[0049] (3)Heat treatment: The precursor solution C obtained in step (2) was evenly coated on the titanium sheet and dried in an oven at 105 °C for 10 min to form a film on the titanium sheet. After drying, it was heated in a muffle furnace at 500 °C for 10 min for thermal decomposition of the film, so that SnCl2, NiBr2, Gd(NO3)3·xH2O and SbCl3 were decomposed and oxidized. This step was repeated 12 times.

[0050] The schematic diagram of the transmission electron microscope at 10 μm and the scanning electron microscope at 5 μm of the titanium-based tin-antimony-nickel-gadolinium coating electrode obtained in Example 2 are respectively as Figure 4 and Figure 5 shown. The catalyst is evenly distributed and the coating is dense, which is beneficial to the reaction of electrolytic water to produce ozone.

[0051] The titanium-based tin-antimony-nickel-gadolinium coating electrode of Example 2 was used for the reaction of electrolyzing water to prepare ozone:

[0052] During the preparation process of the electrode anode using the electrode prepared in Example 1, the electrode added in Example 1 was replaced with the electrode prepared in Example 2 of the same size, and the remaining operating conditions were the same as those in the experiment of electrolyzing water to prepare ozone in Example 1. The change relationship of the ozone concentration produced by the electrolytic water catalytic reaction with the reaction time is as Figure 12 shown. The ozone concentration was above 100 ppm during the tested 10 h, and the curve was relatively stable, indicating that the titanium-based tin-antimony-nickel-gadolinium coating electrode can stably produce ozone under acidic conditions.

[0053] Example 3

[0054] Prepare a Ti / SnO2-Sb-Ni-Fe electrode, including the following steps:

[0055] (1)Pretreatment of titanium sheet: Cut the titanium plate into a plurality of titanium sheets of the same size of 20 mm × 20 mm; first use a 100-mesh coarse sandpaper wheel, and then use a 600-mesh fine sandpaper wheel to mechanically polish the surface of the titanium substrate so that the surface of the electrode shows a silver-white metallic luster. Then put the titanium sheet into a sodium hydroxide solution with a mass concentration of 20%, and carry out a constant temperature heating treatment in an oil bath at 60 °C for 1 h to remove the surface oil stain. After washing with deionized water, soak the above titanium substrate in an oxalic acid solution with a mass concentration of 20%, and carry out a constant temperature heating in an oil bath at 60 °C for 3 h. After the surface of the titanium substrate shows a pitted state, take it out, rinse it with ultrapure water, and put it into a vacuum drying oven for drying.

[0056] (2)Preparation of the precursor solution: Add 8 g of SnSO4, 250 mg of NiCl2·6H2O, 150 mg of FeCl3, and 250 mg of CTAB. Add 12.5 ml of isopropanol as the solvent and ultrasonicate for 30 min to mix them thoroughly, denoted as solution A. Add 238 mg of Sb2O3, transfer 0.20 ml of concentrated hydrochloric acid to dissolve it, add 12.5 ml of isopropanol as the solvent, and ultrasonicate for 30 min to mix them thoroughly, denoted as solution B. Directly mix solution A and B to obtain the required precursor solution C.

[0057] (3)Heat treatment: Uniformly coat the precursor solution C obtained in step (2) on the titanium sheet, dry it in an oven at 108 °C for 9 min to form a film on the titanium sheet; after drying, heat it in a muffle furnace at 530 °C for 6 min to thermally decompose the film, so that SnSO4, NiCl2·6H2O, FeCl3, and SbCl3 decompose and oxidize, and repeat this step 12 times.

[0058] The schematic diagram of the transmission electron microscope at 10 μm and the scanning electron microscope at 5 μm of the titanium-based tin-antimony-nickel-iron coated electrode obtained in Example 3 are respectively as Figure 6 and Figure 7 shown, which is the typical "cracked" morphology of the DSA electrode, has a large contact area with the electrolyte, and can stably generate ozone for a long time.

[0059] The titanium-based tin-antimony-nickel-iron coated electrode of Example 3 is used for the reaction of electrolyzing water to prepare ozone:

[0060] During the preparation process of the electrode anode using the electrode prepared in Example 1, replace the electrode of Example 1 added with an electrode of the same size prepared in Example 3, and the other operating conditions are the same as those in the electrolytic water ozone preparation experiment of Example 1. The variation relationship of the ozone concentration generated by the electrolytic water catalytic reaction with the reaction time is as Figure 12 shown. The gaseous ozone concentration at the beginning of electrolysis of the titanium-based tin-antimony-nickel-iron coated electrode is not much different from the gaseous ozone concentration after 10 h, indicating that the catalyst has good stability.

[0061] Example 4

[0062] Prepare a Ti / SnO2-Sb-Ni-Co electrode, including the following steps:

[0063] (1) Pretreatment of titanium sheet: Cut the titanium plate into multiple 20mm×20mm titanium sheets of the same size; first use a 50-mesh coarse sandpaper wheel and then a 400-mesh fine sandpaper wheel to mechanically polish the surface of the titanium substrate to make the electrode surface appear silvery white. Then put the titanium sheet into a 10% sodium hydroxide solution and heat it in an oil bath at 60°C for 1 hour to remove surface oil stains. After washing with deionized water, soak the titanium substrate in a 10% oxalic acid solution and heat it in an oil bath at 60°C for 2 hours. When the surface of the titanium substrate becomes pockmarked, take it out, rinse it with ultrapure water, and dry it in a vacuum drying oven.

[0064] (2) Preparation of precursor solution: Add 4g SnSO4, 120mg NiBr2, 250mg Co(NO3)3·6H2O and 200mg P123, add 12.5ml isopropanol as solvent, and mix thoroughly by ultrasonication for 30min, which is referred to as solution A. Add 200.6mg Sb2O5, transfer 0.23ml concentrated hydrochloric acid to dissolve it, add 12.5ml isopropanol as solvent, and mix thoroughly by ultrasonication for 30min, which is referred to as solution B. Directly mix solutions A and B to obtain the desired precursor solution C.

[0065] (3) Heat treatment: The precursor solution C obtained in step (2) is evenly applied on the titanium sheet and dried in an oven at 75°C for 8 min to form a film on the titanium sheet; after drying, the film is heated in a muffle furnace at 500°C for 18 min to thermally decompose Sn(NO3)2, NiBr2, Co(NO3)3·6H2O and SbCl3 to decompose and oxidize, and this step is repeated 12 times.

[0066] The transmission electron microscope diagram of the titanium-based tin-antimony-nickel-cobalt coating electrode obtained in Example 4 at 20 μm and the scanning electron microscope diagram at 10 μm are shown in Figures 1 and 2. Figure 8 and Figure 9 As shown, it is a "honeycomb" morphology, and the diameter of the honeycomb is about 5um.

[0067] The titanium-based tin-antimony-nickel-cobalt coating electrode of Example 4 is used for electrolysis of water to produce ozone:

[0068] In the process of preparing the electrode anode prepared by the electrode prepared in Example 1, the electrode prepared in Example 1 is replaced with an electrode prepared in Example 4 of the same size. The remaining operating conditions are the same as the experimental process of preparing ozone by electrolysis of water in Example 1. The relationship between the concentration of ozone generated by the electrolysis of water catalysis and the reaction time is as follows: Figure 12 As shown, the gaseous ozone concentration of the titanium-based tin-antimony-nickel-cobalt coated electrode tends to decrease over time, but the difference is not large.

[0069] Example 5

[0070] Prepare a Ti / SnO2-Sb-Ni-La electrode, including the following steps:

[0071] (1) Pretreatment of titanium sheet: Cut the titanium plate into a plurality of titanium sheets of the same size of 20mm×20mm; first use an 80-mesh coarse sandpaper wheel, and then use a 500-mesh fine sandpaper wheel to mechanically polish the surface of the titanium substrate so that the electrode surface shows a silver-white metallic luster. Then put the titanium sheet into a sodium hydroxide solution with a mass concentration of 15%, and perform a constant temperature heating treatment in an oil bath at 60°C for 1h to remove the surface oil. After washing with deionized water, immerse the above titanium substrate in an oxalic acid solution with a mass concentration of 10%, and perform a constant temperature heating in an oil bath at 60°C for 2h. After the surface of the titanium substrate shows a pitted state, take it out, rinse it thoroughly with ultrapure water, and put it in a vacuum drying oven for drying.

[0072] (2) Preparation of precursor solution: Add 5.2g of SnCl4·5H2O, 130mg of NiCl2·6H2O, 113.2mg of LaCl3 and 180mg of PEG, add 12.5ml of isopropanol as a solvent, and ultrasonically mix for 30min to make it fully mixed, denoted as solution A. Add 200.5mg of Sb2O5, transfer 0.29ml of concentrated hydrochloric acid to dissolve it, add 12.5ml of isopropanol as a solvent, and ultrasonically mix for 30min to make it fully mixed, denoted as solution B. Directly mix solution A and B to obtain the required precursor solution C.

[0073] (3) Heat treatment: Uniformly apply the precursor solution C obtained in step (2) on the titanium sheet, dry it in an oven at 105°C for 5min to form a film on the titanium sheet; after drying, heat it in a muffle furnace at 530°C for 14min to thermally decompose the film, so that SnCl4·5H2O, NiCl2·6H2O, LaCl3 and SbCl3 are decomposed and oxidized, and repeat this step 12 times.

[0074] The schematic diagram of the transmission electron microscope of the titanium-based tin-antimony-nickel-lanthanum coating electrode obtained in Example 5 at 20um and the schematic diagram of the scanning electron microscope at 8um are respectively as Figure 10 and Figure 11 shown. The coating on the surface of the electrolytic plate is evenly distributed and can completely cover the Ti substrate.

[0075] The titanium-based tin-antimony-nickel-lanthanum coating electrode of Example 5 is used for the reaction of electrolyzing water to prepare ozone:

[0076] During the preparation process of the electrode for the anode of the electrode prepared in Example 1, replace the electrode added in Example 1 with the electrode prepared in Example 5 of the same size, and the other operating conditions are the same as those in the electrolytic water ozone preparation experiment process of Example 1. The change relationship of the ozone concentration generated by the electrolytic water catalytic reaction with the reaction time is as Figure 12 shown. From the start of the test, the gaseous ozone concentration of the titanium-based tin-antimony-nickel-lanthanum coating electrode has been stable at about 80ppm.

[0077] Example 6

[0078] A Ti / SnO2-Sb-Ni-Cu electrode is prepared, comprising the following steps:

[0079] (1) Pretreatment of titanium sheet: Cut the titanium plate into multiple 20mm×20mm titanium sheets of the same size; first use a 50-mesh coarse sandpaper wheel and then a 400-mesh fine sandpaper wheel to mechanically polish the surface of the titanium substrate to make the electrode surface appear silvery white. Then put the titanium sheet into a 20% sodium hydroxide solution and heat it in an oil bath at 60°C for 1 hour to remove surface oil stains. After washing with deionized water, soak the titanium substrate in a 10% oxalic acid solution and heat it in an oil bath at 60°C for 2 hours. When the surface of the titanium substrate becomes pockmarked, take it out, rinse it with ultrapure water, and dry it in a vacuum drying oven.

[0080] (2) Preparation of precursor solution: Add 5.78g SnCl4·5H2O, 210mg NiCl2·6H2O, 61.9mg CuCl2 and 230mg F127, add 12.5ml isopropanol as solvent, and mix thoroughly by ultrasonication for 30min, which is recorded as solution A. Add 212.4mg Sb2O3, pipette 0.36ml concentrated hydrochloric acid to dissolve it, add 12.5ml isopropanol as solvent, and mix thoroughly by ultrasonication for 30min, which is recorded as solution B. Solutions A and B are directly mixed to obtain the desired precursor solution C.

[0081] (3) Heat treatment: The precursor solution C obtained in step (2) is evenly applied on the titanium sheet and dried in an oven at 103°C for 12 min to form a film on the titanium sheet; after drying, the film is heated at 570°C in a muffle furnace for 8 min to thermally decompose SnCl4·5H2O, NiCl2·6H2O, CuCl2 and SbCl3 to decompose and oxidize, and this step is repeated 12 times.

[0082] The titanium-based tin-antimony-nickel-copper coated electrode of Example 6 is used for electrolysis of water to produce ozone:

[0083] In the process of preparing the electrode anode prepared by the electrode prepared in Example 1, the electrode of Example 1 added is replaced with an electrode prepared in Example 6 of the same size. The remaining operating conditions are the same as the experimental process of preparing ozone by electrolysis of water in Example 1. The relationship between the concentration of ozone generated by the electrolysis of water catalysis and the reaction time is as follows: Figure 12 As shown, the gaseous ozone concentration of the titanium-based tin-antimony-nickel-copper coated electrode can reach 100 ppm and the concentration is 56 ppm after 10 hours.

[0084] Example 7

[0085] To prepare a Ti / SnO2-Sb-Ni-Pd electrode, the following steps are included:

[0086] (1) Pretreatment of titanium sheet: Cut the titanium plate into a plurality of titanium sheets of the same size of 20 mm × 20 mm; first use a 100-mesh coarse sandpaper wheel, and then use a 320-mesh fine sandpaper wheel to mechanically polish the surface of the titanium substrate so that the surface of the electrode shows a silver-white metallic luster. Then put the titanium sheet into a sodium hydroxide solution with a mass concentration of 15%, and carry out a constant temperature heating treatment in an oil bath at 60 °C for 1 h to remove the surface oil stain. After washing with ionized water, soak the above titanium substrate in an oxalic acid solution with a mass concentration of 10%, and carry out a constant temperature heating in an oil bath at 60 °C for 2 h. After the surface of the titanium substrate shows a pitted state, take it out, rinse it with ultrapure water, and put it into a vacuum drying oven for drying.

[0087] (2) Preparation of precursor solution: Add 4.56 g of SnCl4·5H2O, 125 mg of NiCl2·6H2O, 113.2 mg of Pb(NO3)2·2H2O and 200 mg of F127, add 12.5 ml of isopropanol as a solvent, and ultrasonically mix for 30 min to make them fully mixed, denoted as solution A. Add 205.3 mg of Sb2O3, pipette 0.41 ml of concentrated hydrochloric acid to dissolve it, add 12.5 ml of isopropanol as a solvent, and ultrasonically mix for 30 min to make them fully mixed, denoted as solution B. Directly mix solution A and B to obtain the required precursor solution C.

[0088] (3) Heat treatment: Uniformly brush the precursor solution C obtained in step (2) on the titanium sheet, dry it in an oven at 110 °C for 5 min to form a film on the titanium sheet; after drying, heat it in a muffle furnace at 550 °C for 16 min to carry out thermal decomposition of the film, so that SnCl4·5H2O, NiCl2·6H2O, Pb(NO3)2·2H2O and SbCl3 are decomposed and oxidized, and repeat this step 12 times.

[0089] The titanium-based tin-antimony-nickel-palladium coated electrode of Example 7 is used for the reaction of preparing ozone by electrolyzing water:

[0090] During the preparation process of the electrode anode using the electrode prepared in Example 1, replace the electrode of Example 1 added with an electrode of the same size prepared in Example 7, and the other operating conditions are the same as those in the experiment of preparing ozone by electrolyzing water in Example 1. The variation relationship of the ozone concentration generated by the electrolytic water catalytic reaction with the reaction time is as Figure 12 shown. The gaseous ozone concentration of the titanium-based tin-antimony-nickel-palladium coated electrode increases rapidly, and the gaseous ozone concentration is 35 ppm after 10 h.

[0091] Example 8: To prepare a Ti / SnO2-Sb-Ni-Mn electrode, the following steps are included:

[0092] (1) Pretreatment of titanium sheets: Cut the titanium plates into a plurality of titanium sheets of the same size; first use a coarse sandpaper wheel of 80 mesh, and then use a fine sandpaper wheel of 320 mesh to mechanically polish the surface of the titanium substrate so that the surface of the electrode shows a silver-white metallic luster. Then put the titanium sheets into a sodium hydroxide solution with a mass fraction of 15% and treat for 1 h to remove the surface oil. After washing with distilled water, soak the above-mentioned titanium substrate in a 15% oxalic acid solution and heat it in an oil bath at a constant temperature for 2 h. After the surface of the titanium substrate shows a pitted state, take it out and rinse it thoroughly with ultrapure water.

[0093] (2) Preparation of precursor solution: Add 4.26 g of SnCl2, 117 mg of NiCl2·6H2O, 165.4 mg of Mn(NO3)2 and 150 mg of F127, add 12.5 ml of isopropanol as a solvent, and ultrasonically mix for 30 min to make them fully mixed, denoted as solution A. Add 202.8 mg of Sb2O3, pipette 0.52 ml of concentrated hydrochloric acid to dissolve it, add 12.5 ml of isopropanol as a solvent, and ultrasonically mix for 30 min to make them fully mixed, denoted as solution B. Mix solution A and B directly to obtain the required precursor solution C.

[0094] (3) Heat treatment: Uniformly brush the precursor solution C obtained in step (2) on the titanium sheets, dry it in an oven at 85 °C for 12 min to form a film on the titanium sheets; after drying, heat it in a muffle furnace at 600 °C for 20 min to thermally decompose the film, so that SnCl2, NiCl2·6H2O, Mn(NO3)2 and SbCl3 are decomposed and oxidized, and repeat this step 12 times.

[0095] The titanium-based tin-antimony-manganese coated electrode of Example 8 is used for the reaction of electrolyzing water to prepare ozone:

[0096] In the process of preparing the electrode anode using the electrode prepared in Example 1, replace the electrode added in Example 1 with the electrode prepared in Example 8 of the same size, and the other operating conditions are the same as those in the experiment of electrolyzing water to prepare ozone in Example 1. The change relationship of the ozone concentration generated by the electrolytic water catalytic reaction with the reaction time is as Figure 12 shown. The curve of the titanium-based tin-antimony-manganese coated electrode is similar to that of the titanium-based tin-antimony-nickel-palladium coated electrode.

[0097] The above-described embodiments are only a preferred solution of the present invention, and do not impose any form of limitation on the present invention. There are other variants and modifications without exceeding the technical solutions recorded in the claims.

Claims

1. Application of a titanium-based tin-antimony-nickel metal coating electrode in electrocatalytic water decomposition for ozone production, characterized in that, It includes the following steps: Controlled by a galvanostat, the reaction is carried out in a single electrolytic cell with 0.5 M sulfuric acid as the electrolyte. The titanium-based tin-antimony-nickel metal-coated electrode is used as the working electrode, and a platinum sheet is used as the counter electrode. The reaction current is set to 1 A for electrocatalytic ozone production. The preparation method of the titanium-based tin-antimony-nickel metal-coated electrode includes the following steps: 1) Pretreatment of titanium sheet: Cut the porous titanium plate into titanium sheets, polish the titanium sheets until the surface shows a silver-white metallic luster. Immerse the polished titanium sheets in a sodium hydroxide solution, and heat them in an oil bath to remove the surface oil. Then wash the titanium sheets with deionized water. After washing, soak the titanium sheets in an oxalic acid solution and heat them in an oil bath. After heating is completed, take them out and wash them with ultrapure water, and then put them in a vacuum drying oven for drying. 2) Preparation of precursor solution: Add a tin compound, a nickel compound, a compound of other metal M, and a surfactant to isopropanol in sequence, and ultrasonically mix them to form solution A. Add an antimony compound to isopropanol and add concentrated hydrochloric acid to dissolve it, and ultrasonically mix them to form solution B. Mix solution A and solution B to form precursor solution C. 3) Heat treatment: Uniformly brush the precursor solution C prepared in step 2) on both sides of the titanium sheet treated in step 1), dry it in an oven to form a film on the titanium sheet, and then heat it in a muffle furnace after drying to decompose the film. Repeat this step 5 - 15 times. The compound of other metal M is a nitrate or chloride of Ce, Gd, Fe, Co, La, Cu, Pd or Mn.

2. The application according to claim 1, wherein In step 1), the mass concentration of the sodium hydroxide solution is 5 - 20%, the mass concentration of the oxalic acid solution is 5 - 20%, and the oil bath temperature is 60 - 100 °C.

3. The application according to claim 1, characterized in that, In step 2), the tin compound is tin tetrachloride pentahydrate, stannous chloride or stannous sulfate, the nickel compound is nickel dichloride hexahydrate or nickel bromide, the antimony compound is antimony trioxide or antimony pentoxide, and the surfactant is PVP, CTAB, P123, F127 or PEG.

4. The application according to claim 3, characterized in that, In step 2), the molar ratio of Sn, Sb, Ni, and metal M is 10 - 90:1 - 15:1 - 20:1 - 10.

5. The application according to claim 4, wherein In step 2), the concentration of the tin compound in precursor solution C is 100 g / L - 320 g / L, the concentration of the nickel compound is 3 g / L - 10 g / L, the concentration of the antimony compound is 3 g / L - 10 g / L, the concentration of the metal M compound is 2 g / L - 10 g / L, and the concentration of the surfactant is 2 g / L - 20 g / L.

6. The application according to claim 1, characterized in that, In step 3), the drying temperature in the oven is 60 - 150 °C, the drying time is 5 - 20 min, the heating temperature in the muffle furnace is 500 - 800 °C, and the time is 5 - 20 min.

7. The application according to claim 1, characterized in that, In step 2), the molar ratio of concentrated hydrochloric acid to the antimony compound is 2 - 10:1.

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