Preparation method and application of gold-loaded perovskite-like material

Abstract

The invention discloses a preparation method of a gold-loaded perovskite-like material. The preparation method comprises the following steps: adding zinc acetate into water; then adding sodium stannate, and stirring for half an hour; heating the mixed solution in an air dry oven; after the reaction is completed, cleaning the sample; then drying to obtain a precursor zinc hydroxystannate; placing the sample in a muffle furnace, heating, and annealing to obtain a zinc stannate catalyst; the method comprises the following steps: adding a zinc stannate catalyst into a methanol-containing aqueous solution, stirring, then adding a chloroauric acid aqueous solution, illuminating by a xenon lamp, and stirring; and after the reaction is finished, filtering and collecting a sample, and drying to form Au-ZnSnO3. According to the invention, gold is loaded on the surface of the ZnSnO3 catalyst, so that the problems of insufficient charge migration rate and active sites of a piezoelectric catalytic material are solved, and the efficient performance of producing hydrogen by piezoelectric catalytic decomposition of water is realized. And gold is loaded on the surface of the ZnSnO3 catalyst, so that free charge migration is improved, active sites of the reaction are also provided, and the piezoelectric catalytic hydrogen production rate is further improved.

Description

Technical Field

[0001] The present invention relates to the technical field of piezoelectric catalysts, and particularly to a preparation method and application of a gold-loaded perovskite-like material. Background Art

[0002] Hydrogen (H2), as a clean and efficient renewable energy source, has broad application prospects in the fields of energy, chemical industry, transportation, etc. With the rapid growth of the global demand for hydrogen energy, the contradiction between supply and demand of hydrogen has become increasingly prominent. However, the hydrogen production technologies commonly used in industry at present mainly rely on natural gas reforming and water electrolysis, and these two methods respectively have problems such as high carbon emissions, high energy consumption or high cost. In addition, the storage and transportation of hydrogen require high-pressure or low-temperature conditions, which increase the equipment cost and safety hazards. Therefore, it is urgent to develop an environmentally friendly, efficient and safe hydrogen production technology.

[0003] Piezoelectric catalysis, as a new redox technology, can effectively collect and utilize mechanical energies in the environment such as vibration, wind energy and water waves. This process involves the efficient coupling of the piezoelectric effect and electrochemical reactions, realizing the conversion of mechanical energy into chemical energy, and is a green and safe hydrogen production technology. Among many piezoelectric catalysts, perovskite-like structure catalysts not only have good polarization intensity, but also have advantages such as stable structure and non-toxicity, showing great potential in the field of piezoelectric catalysis. That is, during the piezoelectric catalysis reaction, negative charges can react with hydrogen ions in water to reduce water to hydrogen. However, due to the insufficient charge migration rate and the number of active sites of perovskite-like materials, the generated negative charges cannot quickly migrate to the reaction sites, and at the same time, there are not enough sites to activate hydrogen ions, which limits the efficient hydrogen production of such piezoelectric catalytic materials. Therefore, developing efficient piezoelectric catalysts and strategies to improve piezoelectric catalytic performance is crucial for the practical application of piezoelectric electrocatalysis technology. Summary of the Invention

[0004] Aiming at the problems that the charge migration rate and the number of active sites of the existing perovskite-like materials are insufficient, resulting in the generated negative charges not being able to quickly migrate to the reaction sites and there not being enough sites to activate hydrogen ions at the same time, the present invention proposes a preparation method and application of a gold-loaded perovskite-like material.

[0005] The preparation method of the gold-loaded perovskite-like material includes the following steps:

[0006] S1. Add zinc acetate to water and stir until it completely dissolves to form a transparent solution. Then add sodium stannate and stir for half an hour until a homogeneous white solution is formed. Then transfer the mixed solution to the inner lining of a reaction kettle, place it in a stainless-steel outer shell, and heat it in a forced-air drying oven. After the reaction is completed and cooled to room temperature, wash the sample by centrifugation and with ultrapure water. Then dry it to obtain the precursor zinc hydroxystannate. Place this sample in a muffle furnace, heat it up and then carry out annealing treatment to obtain the zinc stannate catalyst.

[0007] S2. Add the zinc stannate catalyst to an aqueous solution containing methanol and stir to disperse it evenly. Then add an aqueous solution of chloroauric acid, irradiate it with xenon lamp light and stir for 1 h. After the reaction is completed, filter and collect the sample, and place it in a forced-air drying oven to dry and form the gold-loaded zinc stannate catalyst Au-ZnSnO3.

[0008] In a preferred embodiment of the present invention, in S1, specifically: add 0.6585 g of zinc acetate to 30 mL of water and stir until it completely dissolves to form a transparent solution. Then add 0.8002 g of sodium stannate and stir for half an hour until a homogeneous white solution is formed. Then transfer the mixed solution to the inner lining of a reaction kettle, place it in a stainless-steel outer shell, and heat it in a forced-air drying oven. After the reaction is completed and cooled to room temperature, wash the sample by centrifugation and with ultrapure water. Then dry it to obtain the precursor zinc hydroxystannate. Then place this sample in a muffle furnace, heat it up and then carry out annealing treatment to obtain the zinc stannate catalyst.

[0009] Further, in S1, when heating in the forced-air drying oven, the temperature is 210 °C and it is maintained for 24 h.

[0010] Further, after washing the sample in S1, dry it at 70 °C for 24 h to obtain the precursor zinc hydroxystannate.

[0011] Further, in S1, place the sample in a muffle furnace, heat it at a heating rate of 5 °C / min, and carry out annealing treatment at 600 °C for 3 h to obtain the zinc stannate catalyst.

[0012] In a preferred embodiment of the present invention, in S2, specifically: add 100 mg of the zinc stannate catalyst to 30 mL of a 10 vol% aqueous solution containing methanol and stir to disperse it evenly. Then add 200 μL of a 1 mg / mL aqueous solution of chloroauric acid, irradiate it with xenon lamp light and stir for 1 h. After the reaction is completed, filter and collect the sample, and place it in a forced-air drying oven to dry and form the gold-loaded zinc stannate catalyst Au-ZnSnO3.

[0013] Further, in S2, in the forced-air drying oven, dry it at 70 °C to form the gold-loaded zinc stannate catalyst Au-ZnSnO3.

[0014] The prepared zinc stannate catalyst Au-ZnSnO3 by the above preparation method of gold-loaded perovskite-like materials is applied to the field of piezoelectric catalytic hydrogen production.

[0015] Implementing the embodiments of the present invention has the following beneficial effects:

[0016] The present invention prepares a perovskite-like catalyst ZnSnO3 with good piezoelectric catalytic performance. By loading gold on the surface of the ZnSnO3 catalyst, the problems of insufficient charge migration rate and active sites of the piezoelectric catalytic material are solved, and efficient piezoelectric catalytic water splitting hydrogen production performance is achieved. By loading gold on the surface of the ZnSnO3 catalyst, while enhancing the free charge migration, active sites for the reaction are also provided, further enhancing the piezoelectric catalytic hydrogen production rate, and the performance is improved by about 2.68 times, killing two birds with one stone. Description of the Drawings

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0018] Figure 1 It is the XRD pattern of the zinc stannate catalyst;

[0019] Figure 2 It is the TEM image (left) and EDS image (right) of the Au-ZnSnO3 catalyst;

[0020] Figure 3 It is a schematic diagram of piezoelectric catalytic hydrogen production by the ZnSnO3 or Au-ZnSnO3 catalyst;

[0021] Figure 4 It is a schematic diagram of piezoelectric catalytic hydrogen production by the Au-ZnSnO3 catalyst; Detailed Embodiments

[0022] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the protection scope of the present invention.

[0023] The preparation method of the present gold-loaded perovskite-like material includes the following steps:

[0024] S1. Add 0.6585 g of zinc acetate to 30 mL of water and stir until completely dissolved to form a transparent solution. Then add 0.8002 g of sodium stannate and stir for half an hour until a homogeneous white solution is formed. Then transfer the mixed solution to the inner lining of the reaction kettle, place it in the stainless-steel outer shell, and heat it in a forced-air drying oven at a temperature of 210 °C for 24 h. After the reaction is completed and cooled to room temperature, wash the sample by centrifugation and washing with ultrapure water. Then dry it at 70 °C for 24 h to obtain the precursor zinc hydroxystannate. Then place the sample in a muffle furnace and anneal it at 600 °C for 3 h at a heating rate of 5 °C / min to obtain the zinc stannate catalyst. Please refer to Figure 1 , Figure 1 which is the XRD pattern of the zinc stannate catalyst.

[0025] S2. Add 100 mg of the zinc stannate catalyst to 30 mL of an aqueous solution containing 10 vol% methanol and stir to disperse it evenly. Then add 200 μL of a 1 mg / mL chloroauric acid aqueous solution, irradiate it with xenon lamp light and stir for 1 h. After the reaction is completed, filter and collect the sample, and dry it in a forced-air drying oven at 70 °C to form the gold-loaded zinc stannate catalyst Au-ZnSnO3. Please refer to Figure 2 , Figure 2 which is the TEM image (left) and EDS image (right) of the Au-ZnSnO3 catalyst; Figure 2 It can be observed from the transmission electron microscope results that gold is successfully loaded on the surface of the zinc stannate catalyst, and obvious gold nanoparticles are detected on the catalyst surface by EDS.

[0026] Through the above preparation method of the gold-loaded perovskite-like material, the prepared zinc stannate catalyst Au-ZnSnO3 is applied to the field of piezoelectric catalysis for hydrogen production.

[0027] Performance study:

[0028] The piezoelectric catalysis for hydrogen production using the ZnSnO3 or Au-ZnSnO3 catalyst is as follows:

[0029] Disperse the ZnSnO3 or Au-ZnSnO3 catalyst evenly in 10 mL of an aqueous solution containing 20% ethylene glycol. Here, ethylene glycol is used as a sacrificial agent to consume the positive charge during the reaction, and then replace the air in the reaction vessel with argon and seal it. Then place the vessel in an ultrasonic machine to start the reaction. The amount of the catalyst is 10 mg, the power of the ultrasonic machine is 120 W, and the frequency is 80 kHz. The reaction temperature is maintained at room temperature, about 25 °C, throughout the reaction process by circulating cooling water. The hydrogen production is detected by gas chromatography, and the experimental results are as Figure 3 shown.

[0030] Figure 3The results in -1 ·h -1 showed that the hydrogen production rate of the Au-ZnSnO3 catalyst could reach ~11.62 mmol·g -1 ·h -1 in an argon atmosphere with ethylene glycol as the positive charge capturer, which was 2.68 times that of ZnSnO3 (~3.16 mmol·g

[0031] ·h

[0032] -1 Figure 4 ). Loading gold nanoparticles on the surface of the catalyst improved the charge migration rate of the original material and provided sufficient reactive sites, thus enhancing the overall hydrogen production rate. Figure 4 Au-ZnSnO3 piezoelectric catalysis for hydrogen production control, the specific process is as follows:

[0033] Disperse Au-ZnSnO3 in the solution. The experimental preparation process and test method are the same as above. Parallel controls were conducted on the catalyst, the positive charge sacrificial agent ethylene glycol, and ultrasonic vibration. In addition, potassium bromate was selected as the negative charge sacrificial agent for relevant research. Please refer to

[0034]

[0035]

[0036]

[0037] Figure 18 for the schematic diagram of piezoelectric catalysis for hydrogen production by the Au-ZnSnO3 catalyst.

[0034] Please refer to Table 1, which is a comparison table of the piezoelectric catalysis hydrogen production rates of different catalysts under different reaction conditions.

[0035]

[0036] [[ID=4,3]]Table 1 Comparison table of piezoelectric catalysis hydrogen production rates of different catalysts under different reaction conditions

[0037]

[0038] The results in Table 1 showed that when ethylene glycol was used as the positive charge capturer, the hydrogen production rate of the Au-ZnSnO3 catalyst was ~11.62 mmol·g -1 ·h -1 , which was about 4.7 times higher than the hydrogen production rate of ~2.45 mmol·g -1 ·h -1 without adding ethylene glycol. Then, by adding potassium bromate as the negative charge capturer, a significant decrease in the hydrogen production rate (~0.83 mmol·g -1 ·h -1 ) was observed, indicating that negative charges were the main active substances reacting with hydrogen ions to produce hydrogen during the reaction. Then, it was observed that almost no hydrogen was produced in the absence of the catalyst or ultrasonic vibration. This indicated that the cavitation effect induced by ultrasonic vibration during the reaction drove the catalyst to generate positive and negative charges, which further reacted with water to produce hydrogen.

[0038] The present invention prepares a perovskite - type catalyst ZnSnO3 with good piezocatalytic performance. Piezocatalysis, as a new type of redox technology, has currently been widely studied for wastewater treatment, hydrogen production, carbon dioxide reduction, etc. However, common catalysts currently often cannot effectively drive catalytic reactions due to problems such as slow free - charge separation rate and insufficient active sites, which also hinders practical applications. By loading gold on the surface of the ZnSnO3 catalyst, the problems of charge migration rate and insufficient active sites of such materials are solved, and efficient piezocatalytic hydrogen production performance by water decomposition is achieved. Moreover, by loading gold on the surface of the ZnSnO3 catalyst, while enhancing the migration of free charges, active sites for the reaction are also provided, further enhancing the piezocatalytic hydrogen production rate, and the performance is improved by about 2.68 times.

[0039] The above - mentioned are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for preparing a gold-loaded perovskite-like material, characterized in that It includes the following steps: S1. Add zinc acetate into water, stir until it is completely dissolved to form a transparent solution; then add sodium stannate, stir for half an hour until a uniform white solution is formed; then transfer the mixed solution to the inner lining of the reaction kettle, put it into the stainless steel outer shell, and place it in a forced air drying oven for heating; after the reaction is completed and cooled to room temperature, wash the sample by centrifugation and washing with ultrapure water; then dry to obtain the precursor zinc stannate hydroxide; put this sample in a muffle furnace, heat it up and then carry out annealing treatment to obtain the zinc stannate catalyst. S2. Add the zinc stannate catalyst into the aqueous solution containing methanol and stir to disperse it evenly, then add the chloroauric acid aqueous solution, irradiate with xenon lamp light and stir for 1 h; after the reaction is completed, filter and collect the sample, and place it in a forced air drying oven to dry to form the gold-loaded zinc stannate catalyst Au-ZnSnO3.

2. The preparation method of the gold-loaded perovskite-like material according to claim 1, characterized in that, Specifically in S1: Add 0.6585 g of zinc acetate into 30 mL of water, stir until it is completely dissolved to form a transparent solution; then add 0.8002 g of sodium stannate, stir for half an hour until a uniform white solution is formed; then transfer the mixed solution to the inner lining of the reaction kettle, put it into the stainless steel outer shell, and place it in a forced air drying oven for heating; after the reaction is completed and cooled to room temperature, wash the sample by centrifugation and washing with ultrapure water; then dry to obtain the precursor zinc stannate hydroxide; then put this sample in a muffle furnace, heat it up and then carry out annealing treatment to obtain the zinc stannate catalyst.

3. The preparation method of the gold-loaded perovskite-like material according to claim 2, wherein In S1, when heating in the forced air drying oven, the temperature is 210 °C and it is maintained for 24 h.

4. The preparation method of the gold-loaded perovskite-like material according to claim 3, characterized in that, In S1, after washing the sample, dry it at 70 °C for 24 h to obtain the precursor zinc stannate hydroxide.

5. The preparation method of the gold-loaded perovskite-like material according to claim 4, characterized in that, In S1, put the sample in a muffle furnace, with a heating rate of 5 °C / min, and carry out annealing treatment at 600 °C for 3 h to obtain the zinc stannate catalyst.

6. The preparation method of the gold-loaded perovskite-like material according to claim 1, wherein, Specifically in S2: Add 100 mg of the zinc stannate catalyst into 30 mL of 10 vol% aqueous solution containing methanol and stir to disperse it evenly, then add 200 μL of 1 mg / mL chloroauric acid aqueous solution, irradiate with xenon lamp light and stir for 1 h; after the reaction is completed, filter and collect the sample, and place it in a forced air drying oven to dry to form the gold-loaded zinc stannate catalyst Au-ZnSnO3.

7. The preparation method of the gold-loaded perovskite-like material according to claim 6, characterized in that, In S2, in the forced air drying oven, dry it at 70 °C to form the gold-loaded zinc stannate catalyst Au-ZnSnO3.

8. The preparation method of the gold-loaded perovskite-like material according to any one of claims 1-7, characterized in that, The prepared zinc stannate catalyst Au-ZnSnO3 is applied in the field of piezoelectric catalysis for hydrogen production.

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