CN111604048A - Ammonia synthesis method by electrocatalytic reduction of nitrogen and used catalyst - Google Patents
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Abstract
The invention discloses a transition metal monatomic catalyst for electrocatalytic synthesis of ammonia, which is prepared by adopting a photo-deposition method according to the following steps: preparing a carbon material serving as a carrier by using carbon powder, sodium nitrate, concentrated sulfuric acid, potassium permanganate, deionized water and the like; dispersing TiO in mixed solvent of water and organic solvent2And adding a transition metal salt into the carbon material, uniformly mixing, then placing the mixture under illumination to react at room temperature, freezing and solidifying a reaction product, and then carrying out vacuum freeze drying to obtain the transition metal monatomic catalyst. The invention also provides a method for utilizing transition metal monogenThe sub-catalyst is used for electrocatalytic reduction of nitrogen to synthesize ammonia. The method for synthesizing ammonia has the characteristics of simple and economical process, environmental friendliness, high yield and the like.
Description
Technical Field
The invention relates to an electrochemical synthesis method of ammonia.
Background
Ammonia is an important inorganic chemical product and is a main raw material in the fertilizer industry and basic organic chemical industry. In addition, ammonia is also a carbon-free energy carrier, the combustion products of the ammonia are nitrogen and water, the mass produced ammonia can replace most of the liquid fuel consumption at present, the ammonia is considered to be one of green sustainable fuel substances with a promising future, and the application of the ammonia in the fields of heavy transportation, power generation, distributed energy storage and the like is actively developed all over the world. The amount of ammonia is huge, and the demand of ammonia is continuously increased along with the development of industry and agriculture. At present, most of the sources of ammonia in the world are synthetic ammonia except a small amount of byproducts recovered from coke oven gas.
The traditional industrial method for synthesizing ammonia is a Haber-Bosch method, which requires harsh conditions of high temperature and high pressure (about 300-500 ℃, 20.26-30.40 MPa), and the energy consumption caused by the method accounts for about 1.4% of the total energy consumption of the whole world every year. The raw material hydrogen is prepared mainly by decomposing fossil energy, the consumed natural gas in the process accounts for 3-5% of the total natural gas consumption in the world, and a large amount of greenhouse gas is generated.
Up to now, the synthesis of ammonia has undergone three generations of technological changes. The first generation of ammonia synthesis technology involved the use of carbon sequestration or compensation to reduce the net carbon impact of ammonia production to zero. The carbon sequestration in ammonia production adds cost and plant complexity based on existing H-B technology, represents only a transitional solution, contributing to the establishment of ammonia markets beyond the fertilizer and chemical industries.
The second generation of ammonia synthesis technology still adopts the H-B method, but the hydrogen used as the raw material is the hydrogen produced by electrolyzing water. Siemens technicians produce hydrogen by using completely renewable electric energy generated by a 20kW wind turbine through a Proton Exchange Membrane (PEM) electrolytic cell, and about 30 kilograms of ammonia are formed every day (Physical Chemistry Chemical Physics,2012,14(3):1235-1245.), so that the problem that excessive natural gas is consumed in the original process for preparing hydrogen is effectively solved, but the defect of overlarge input energy of high temperature and high pressure in the synthesis process still exists.
The third generation of ammonia synthesis technology electrically reduces nitrogen gas to ammonia directly or indirectly, and the technology completely breaks away from the H-B process. The synthesis reaction is driven by electrochemical reduction, and the hydrogen source is from water. The reaction conditions (normal temperature and normal pressure) in the process are mild, the raw material sources are rich, and the electric energy can be from sustainable energy sources such as solar energy, wind energy and the like, so that the method has an important development prospect. Haiyuan Zou reports that an ultrathin chlorine-doped graphene catalyst is used for electrocatalytic reduction of nitrogen, and the ammonia yield is 10.7 mu g.h under the potential of-0.45V (vs RHE)-1·cm-2mg-1 Cat.The Faraday efficiency is 8.7% (ACCCATALYSIS, 2019,9(12): 10649-. Hongjie Yu reports a film material mAu3Pd/NF is used for electrocatalytic nitrogen reduction, and the ammonia yield is 24.02 mug.h-1·cm-2mg-1 Cat.Faraday efficiency of 18.16% (ACS Applied Materials)&Interfaces,2020,12(1): 436-. Wenjie Zang reports that a nitrogen-doped carbon-supported copper monatomic catalyst is used for electrocatalytic nitrogen reduction, and the obtained ammonia yield is 49.3 mug.h in HCl electrolyte-1·cm-2mg-1 Cat.The Faraday efficiency is 11.7% (ACCCATALYSIS, 2019,9(11): 10166-10173), but the method has the problem that the test result is inaccurate due to the introduction of nitrogen impurities, and the source of nitrogen elements in the product is verified.
In summary, the early H-B method for synthesizing ammonia has the problems of harsh conditions, large energy consumption and the like, and the recent electrochemical synthesis of ammonia has the problems of low yield, low faraday efficiency, expensive catalyst materials, non-uniform test standards and the like, and the efficient green production of ammonia is to be realized, which not only relates to the design of an electrochemical system, but also relates to the development of efficient and economic catalysts.
Disclosure of Invention
The invention solves the technical problem of providing a mild, efficient and green ammonia synthesis method.
In order to solve the technical problems, the invention provides a transition metal monatomic catalyst for synthesizing ammonia by electro-catalysis, which is prepared by adopting a photo-deposition method according to the following steps:
1) preparation of a carbon material (carbon material support) as a support:
uniformly stirring 1g of carbon powder (high-purity carbon powder with the purity of more than or equal to 95%), 1 +/-0.1 g of sodium nitrate and 46 +/-2 mL of concentrated sulfuric acid (sulfuric acid solution with the mass concentration of 95-98%) in an ice bath, adding 6 +/-0.6 g of potassium permanganate, and reacting at 30-40 ℃ for 1 +/-0.2 h; then adding 40 +/-10 mL of deionized water, and heating and reacting at 90 +/-10 ℃ for 30-50 min;
stopping the reaction after the reaction time is up; carrying out post-treatment on the reaction product to obtain a carbon material;
description of the drawings: the carbon material is sealed and then stored at 16-25 ℃;
2) and preparing a transition metal monoatomic catalyst:
firstly, mixing water and an organic solvent to form a mixed solvent;
according to TiO2: carbon material 1: (1. + -. 0.1) by weight, dispersing TiO in the mixed solvent2Adding a transition metal salt into the carbon material, uniformly mixing, then placing the mixture under illumination for reacting at room temperature for 1-6 h, freezing and solidifying a reaction product, and then carrying out vacuum freeze drying to obtain a transition metal monatomic catalyst;
in the transition metal monatomic catalyst, the loading amount of the transition metal element (as an active center) is 0.1 to 10%, preferably 1 to 10%, more preferably 1 to 5%, and most preferably 1%.
In general: 50mg TiO/min2Mixing 20-40 ml of mixed solvent;
as an improvement of the transition metal monatomic catalyst for the electrocatalytic synthesis of ammonia of the present invention, in the step 2): the transition metal is vanadium (V), niobium (Nb) or tantalum (Ta). The transition metal salt is sodium metavanadate, sodium pyrovanadate, sodium orthovanadate, niobium oxalate, potassium niobate, tantalum pentachloride, potassium fluotantalate or potassium metatantalate.
As a further improvement of the transition metal monatomic catalyst for electrocatalytic synthesis of ammonia of the present invention, in said step 2): the organic solvent is methanol, ethanol, isopropanol, butanol, dioxane, dioxolane, diethylene glycol dimethyl ether and ethylene glycol dimethyl ether;
the volume ratio of the water to the organic solvent is 1: 1-10: 1.
As a further improvement of the transition metal monatomic catalyst for electrocatalytic synthesis of ammonia of the present invention, in said step 2): freezing and solidifying the reaction product at-15-25 ℃ for 1.5-2.5 h, and then freezing and drying in vacuum to obtain the transition metal monatomic catalyst.
As a further improvement of the transition metal monatomic catalyst for the electrocatalytic synthesis of ammonia of the present invention, in the step 1), after the reaction time is reached, (100 + -10) mL of deionized water is added to stop the reaction, and then, (6 + -1) mL of hydrogen peroxide solution is added; then repeatedly cleaning with 3% (mass%) hydrochloric acid and deionized water until the pH of the cleaning solution is neutral; and ultrasonically dispersing the cleaned product (the dispersion time is 1-3 h), and carrying out vacuum freeze drying to obtain the carbon material.
Description of the drawings: the hydrogen peroxide acts to reduce the residual oxidizing agent, potassium permanganate.
The invention also provides a method for synthesizing ammonia by carrying out electrocatalysis reduction on nitrogen by using the transition metal monatomic catalyst, which comprises the steps of using an electrocatalysis device of a three-electrode system, arranging a reference electrode RE and a working electrode WE in a cathode electrolytic cell, arranging a counter electrode CE in an anode electrolytic cell, and filling electrolyte in the cathode electrolytic cell and the anode electrolytic cell; and arranging a transition metal monatomic catalyst coating on the surface of the working electrode WE, introducing nitrogen into the electrolyte in the cathode electrolytic cell until the electrolyte is saturated, and applying voltage to carry out electrolysis.
The voltage is, for example, -0.4V (vs RHE), and a chronoamperometric test (CA) is carried out for 2h after electrolysisAnd obtaining the ammonia-containing electrolyte. The ammonia yield can reach as high as 136.4 mug.h-1·cm-2mg-1 Cat.The Faraday efficiency was 53.5%.
According to the preparation method, Graphene Oxide (GO) is prepared as a carbon material carrier for loading the catalyst, and then the types of organic solvents are screened in the process of preparing the monatomic catalyst, so that the proportion of water and the organic solvents in a mixed solvent is optimized, the electronic structure of the catalyst is favorably adjusted, and the catalytic activity of the catalyst is enhanced. The invention also screens the transition metal as the active center, optimizes the loading amount of the active center of the catalyst and is beneficial to improving the activity of a single site in the catalyst.
A schematic diagram of an electrochemical device of the present invention is shown in fig. 1.
The invention relates to an electro-catalysis nitrogen ammonia synthesis method, which develops a novel high-efficiency monatomic catalyst with transition metal as an active center, and electro-catalysis nitrogen is reduced to form ammonia; has the following technical advantages:
1. the prepared monoatomic transition metal catalyst has high activity, the preparation method is relatively simple, and the yield of the catalytic synthesis ammonia is high;
2. in the electrochemical process, nitrogen and water (mainly water in electrolyte) are used as raw materials, so that the raw materials are wide in source, no pollution gas is generated, and the environment friendliness in the production process is ensured;
3. the method for synthesizing ammonia has the characteristics of simple and economical process, environmental friendliness, high yield and the like.
In conclusion, the invention establishes a technical development route for synthesizing ammonia by directly utilizing transition metal monatomic catalyst through comparing the reaction characteristics of different routes and comprehensively considering the difficulty of industrialization of the reaction process, wherein nitrogen and water are used as raw materials. The key technical difficulty is the development of high-efficiency monatomic catalyst.
Drawings
The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.
FIG. 1 is a schematic view of an electrochemical device;
RE represents a reference electrode, WE represents a working electrode, and CE represents a counter electrode.
Detailed Description
The invention will be further described with reference to specific examples, but the scope of the invention is not limited thereto:
hereinafter, the reaction is carried out under conventional stirring conditions; the conditions of vacuum freeze-drying are as follows: vacuum degree of 0.001MPa and-50 ℃.
Example one, preparation of a carbon material (carbon material support) as a support:
uniformly mixing and stirring 1g of high-purity carbon powder (the purity is more than or equal to 95 percent), 1g of sodium nitrate and 46mL of concentrated sulfuric acid (sulfuric acid solution with the mass concentration of 95-98 percent) in an ice bath (about 0 ℃), adding 6g of potassium permanganate, then reacting for 1h at 30-40 ℃, continuously adding 40mL of deionized water, putting the mixture into a water bath with the temperature of 90 ℃ for heating for 30-50 min, taking out the mixture, adding 100mL of deionized water to stop the reaction, and adding 6mL of hydrogen peroxide solution (hydrogen peroxide solution with the mass concentration of 30 percent, wherein the hydrogen peroxide solution has the effect of reducing residual potassium permanganate serving as an oxidant); finally, the washing was repeated with 3% (mass%) hydrochloric acid and deionized water until the pH of the washing solution was close to neutral. Adding about 20ml of water into the cleaned product, performing ultrasonic dispersion for 2h (ultrasonic dispersion is 25 ℃, power is 400W, frequency is 20kHz), and performing vacuum freeze drying for 20 h to obtain a carbon material, wherein the carbon material is sealed and stored at 16-25 ℃.
The following examples all employ this carbon material.
Example 1 preparation of a V/G monatomic catalyst by a photodeposition method:
in the presence of water: 50mgTiO was dispersed in 30ml of a mixed solvent of methanol 8:1(v/v)2And 50mg of carbon material to TiO2Uniformly dispersing the carbon material to obtain a dispersion liquid;
adding about 2.39mg of sodium metavanadate (containing 1mg of vanadium) into the dispersion, then placing the dispersion under the irradiation of a light source to stir and react for 5 hours at room temperature, then freezing the dispersion in a refrigerator for 2 hours at (-20 ℃) until the solution is solidified into a solid, and finally carrying out vacuum freeze drying for 24 hours to obtain 101.0mg of the V/G monatomic catalyst with the mass fraction of 1.0%;
a short-arc xenon lamp current-stabilizing power supply provides a light source, the current is 10A, the power of the xenon lamp is 500W, and the wavelength range of the light source is 320-780 nm.
Example 2 preparation of Nb/G monatomic catalyst by photodeposition:
in the presence of water: 50mgTiO 50mg was dispersed in 30ml of a mixed solvent of 10:1(v/v) isopropyl alcohol2And 50mg of carbon material to TiO2Uniformly dispersing the carbon material to obtain a dispersion liquid;
about 5.79mg of niobium oxalate (containing 1mg of Nb) is added into the dispersion, then the dispersion is placed under a light source to be irradiated at room temperature and stirred for reaction for 3 hours, then the mixture is frozen in a refrigerator for 2 hours until the solution is solidified into a solid, and finally the mixture is frozen and dried in vacuum for 24 hours, so that 101.0mg of Nb/G monatomic catalyst with the mass fraction of 1.0 percent is obtained.
Example 3 preparation of Ta/G monatomic catalyst by photodeposition:
in the presence of water: 50mgTiO was dispersed in 30ml of a mixed solvent of 9:1(v/v) ethanol2And 50mg of carbon material to TiO2Uniformly dispersing the carbon material to obtain a dispersion liquid;
about 0.99mg tantalum pentachloride (containing Ta 1mg) was added to the above dispersion; and then placing the mixture under a light source for irradiation and stirring for reaction for 4 hours, freezing the mixture in a refrigerator for 2 hours until the solution is solidified into a solid, and finally performing vacuum freeze drying for 24 hours to obtain 101.0mg of Ta/G monatomic catalyst with the mass fraction of 1.0%.
Example 4 preparation of a V/G monatomic catalyst by a photodeposition method:
in the presence of water: 50mgTiO 3 ml of a mixed solvent of dioxane 9:1(v/v) was dispersed in 30ml of the mixed solvent2And 50mg of carbon material to TiO2Uniformly dispersing the carbon material to obtain a dispersion liquid;
adding about 3.61mg of sodium orthovanadate (containing V1mg) to the dispersion; and then placing the mixture under a light source for irradiation and stirring for reaction for 6 hours, freezing the mixture in a refrigerator for 2 hours until the solution is solidified into a solid, and finally performing vacuum freeze drying for 24 hours to obtain 101.0mg of the V/G monatomic catalyst with the mass fraction of 1.0%.
Example 5 preparation of Nb/G monatomic catalyst by photodeposition:
in the presence of water: 50mgTiO 50 ml of a mixed solvent of diethylene glycol dimethyl ether 6:1(v/v) was dispersed in 30ml of the mixed solvent2And 50mg of carbon material to TiO2Carbon materialUniformly dispersing to obtain dispersion liquid;
about 9.70mg of potassium niobate (containing 5mg of Nb) was added to the above dispersion; and then placing the mixture under a light source for irradiation and stirring for reaction for 5 hours, freezing the mixture in a refrigerator for 2 hours until the solution is solidified into a solid, and finally performing vacuum freeze drying for 24 hours to obtain 101.0mg of the Nb/G monatomic catalyst with the mass fraction of 5.0%.
Example 6 preparation of Ta/G monatomic catalyst by a photodeposition method:
in the presence of water: 50mgTiO 2 was dispersed in 30ml of a mixed solvent of 1:1(v/v) ethylene diether dimethyl ether2And 50mg of carbon material to TiO2Uniformly dispersing the carbon material to obtain a dispersion liquid;
about 6.51mg potassium fluorotantalate (containing Ta 3mg) was added to the above dispersion; and then placing the mixture under a light source for irradiation and stirring for reaction for 3 hours, freezing the mixture in a refrigerator for 2 hours until the solution is solidified into a solid, and finally performing vacuum freeze drying for 24 hours to obtain 101.0mg of Ta/G monatomic catalyst with the mass fraction of 3.0%.
Experiment 1, an electrocatalysis device is built by adopting a three-electrode system, a reference electrode RE and a working electrode WE are arranged in a cathode electrolytic cell of an H-shaped electrolytic cell, a counter electrode CE is arranged in an anode electrolytic cell, and electrolyte is filled in the cathode electrolytic cell and the anode electrolytic cell, for example, 0.1mol/L sodium sulfate solution is used as the electrolyte; it is common knowledge to apply a voltage to the working electrode WE.
The monatomic catalysts obtained in examples 1 to 6 were subjected to the following experiments: taking 1mg of monatomic catalyst to dissolve in ethanol: a mixed solution of Nafion solution 9:1(v/v) in about 30ml, and sonicated for 1h to obtain a uniform catalyst solution, which was completely coated on a carbon paper of 1cm × 1cm, and dried overnight.
The working electrode is carbon paper coated with a catalyst, the counter electrode is a Pt electrode, and the reference electrode is a saturated calomel electrode. Before testing, nitrogen is introduced at a gas speed of 10mL/min, after the electrolyte is saturated with nitrogen (30 mL electrolyte, about 30min is needed), a voltage of-0.4V (vs RHE) is applied, a timing current test (CA) is carried out, and the electrolyte containing ammonia is obtained after 2h, wherein the ammonia production rate and the Faraday efficiency are as described in the following table 1.
Description of the drawings: the Nafion solution is a perfluorosulfonic acid type polymer solution, having a concentration of 5 wt%, and can be obtained by a conventional commercially available method.
The ammonia yield is calculated by the formula
In the above formula, cNH3The concentration of ammonia is given in μ g. mL-1(ii) a V is the volume of the electrolyte in the cathode electrolytic cell, and the unit is mL; m isCat.Is the supported catalyst mass in mg; a is the area of the catalyst load in cm-2(ii) a t is electrolysis time in h.
TABLE 1
| Catalyst and process for preparing same | Ammonia production rate | Faraday efficiency | |
| Example 1 | 1.0% of a V/G monatomic catalyst | 56.4μg·h-1·cm-2mg-1 Cat | 19.8％ |
| Example 2 | 1.0% Nb/G monatomic catalyst | 95.6μg·h-1·cm-2mg-1 Cat | 25.4％ |
| Example 3 | 1.0% Ta/G monatomic catalyst | 136.4μg·h-1·cm-2mg-1 Cat | 53.5％ |
| Example 4 | 1.0% of a V/G monatomic catalyst | 52.6μg·h-1·cm-2mg-1 Cat | 18.9％ |
| Example 5 | 5.0% Nb/G monatomic catalyst | 75.6μg·h-1·cm-2mg-1 Cat | 20.1％ |
| Example 6 | 3.0% Ta/G monatomic catalyst | 106.5μg·h-1·cm-2mg-1 Cat | 40.1％ |
The mixed solvent in the processes of the comparative example 1 and the example 3 of the single-atom catalyst is changed as shown in the following table 2, the amount of the mixed solvent is kept unchanged, and the rest is equal to the example 3.
A comparison of the final ammonia yield results is shown in Table 2 below.
TABLE 2
Comparative example 2, the tantalum pentachloride containing 1mg of Ta in example 3 was changed to the following salt containing the same amount of Ta, and the rest was the same as example 3.
Detection was carried out as described in experiment 1. A comparison of the final ammonia yield results is shown in Table 3 below.
TABLE 3
| Ammonia production rate (mug. h)-1·cm-2mg-1 Cat.) | ||
| Example 3 | Tantalum pentachloride | 136.4 |
| Comparative example 2 | Potassium fluotantalate | 126.3 |
| Potassium metatantalate | 119.5 |
Comparative example 3, 0.99mg of tantalum pentachloride in example 3 was changed to 2.10mg of copper chloride, and the balance was the same as in example 3. Namely, a Cu/G monatomic catalyst was obtained with a mass fraction of 1.0%.
Detection was carried out as described in experiment 1. The results obtained were: the ammonia yield is 26.5 mug.h-1·cm-2mg-1 Cat.。
Comparative example 4, the carbon material in example 3 was directly changed to commercially available "Graphene Oxide (GO)", with a constant amount of 50 mg; the rest is equivalent to example 3.
Detection was carried out as described in experiment 1. The results obtained were: the ammonia yield is 33.4 mug.h-1·cm-2mg-1 Cat.。
Finally, it is also noted that the above-mentioned lists merely illustrate a few specific embodiments of the invention. It is obvious that the invention is not limited to the above embodiments, but that many variations are possible. All modifications which can be derived or suggested by a person skilled in the art from the disclosure of the present invention are to be considered within the scope of the invention.
Claims (7)
1. Transition metal monatomic catalyst for the electrocatalytic synthesis of ammonia, characterized in that: the preparation method comprises the following steps of:
1) preparing a carbon material as a carrier:
uniformly stirring 1g of carbon powder, (1 +/-0.1) g of sodium nitrate and (46 +/-2) mL of concentrated sulfuric acid in an ice bath, adding (6 +/-0.6) g of potassium permanganate, and reacting at 30-40 ℃ for (1 +/-0.2) h; then adding 40 +/-10 mL of deionized water, and heating and reacting at 90 +/-10 ℃ for 30-50 min;
stopping the reaction after the reaction time is up; carrying out post-treatment on the reaction product to obtain a carbon material;
2) and preparing a transition metal monoatomic catalyst:
firstly, mixing water and an organic solvent to form a mixed solvent;
according to TiO2: carbon material 1: (1. + -. 0.1) by weight, dispersing TiO in the mixed solvent2Mixing with carbon material, adding transition metal salt, mixing, and standing under illumination at room temperatureReacting for 1-6 h, freezing and solidifying the reaction product, and then carrying out vacuum freeze drying to obtain a transition metal monoatomic catalyst;
in the transition metal single-atom catalyst, the load capacity of the transition metal element is 0.1-10%.
2. The transition metal monatomic catalyst for the electrocatalytic synthesis of ammonia according to claim 1, characterized in that:
in the step 2): the transition metal is vanadium (V), niobium (Nb) or tantalum (Ta).
3. The transition metal monatomic catalyst for the electrocatalytic synthesis of ammonia according to claim 2, characterized in that:
the transition metal salt is sodium metavanadate, sodium pyrovanadate, sodium orthovanadate, niobium oxalate, potassium niobate, tantalum pentachloride, potassium fluotantalate or potassium metatantalate.
4. A transition metal monatomic catalyst for the electrocatalytic synthesis of ammonia according to claim 3, characterized in that:
in the step 2): the organic solvent is methanol, ethanol, isopropanol, butanol, dioxane, dioxolane, diethylene glycol dimethyl ether and ethylene glycol dimethyl ether;
the volume ratio of the water to the organic solvent is 1: 1-10: 1.
5. A transition metal monatomic catalyst for the electrocatalytic synthesis of ammonia according to any one of claims 1 to 4, characterized in that:
in the step 2): freezing and solidifying the reaction product at-15-25 ℃ for 1.5-2.5 h, and then freezing and drying in vacuum to obtain the transition metal monatomic catalyst.
6. A transition metal monatomic catalyst for the electrocatalytic synthesis of ammonia according to any one of claims 1 to 4, characterized in that:
in the step 1), after the reaction time is up, adding (100 +/-10) mL of deionized water to stop the reaction, and then adding (6 +/-1) mL of hydrogen peroxide solution; repeatedly cleaning with 3% hydrochloric acid and deionized water until the pH of the cleaning solution is neutral; and (4) carrying out ultrasonic dispersion and vacuum freeze drying on the cleaned product to obtain the carbon material.
7. A method for synthesizing ammonia by carrying out electrocatalytic reduction on nitrogen by using the transition metal monatomic catalyst according to any one of claims 1 to 6, wherein an electrocatalysis device of a three-electrode system is used, a reference electrode RE and a working electrode WE are arranged in a cathode electrolytic cell, a counter electrode CE is arranged in an anode electrolytic cell, and electrolytes are filled in the cathode electrolytic cell and the anode electrolytic cell; the method is characterized in that:
and arranging a transition metal monatomic catalyst coating on the surface of the working electrode WE, introducing nitrogen into the electrolyte in the cathode electrolytic cell until the electrolyte is saturated, and applying voltage to carry out electrolysis.
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| CN113106470A (en) * | 2021-04-06 | 2021-07-13 | 湖州宏兆化工贸易有限公司 | Vanadium-doped titanium dioxide/graphene electrocatalyst suitable for electrochemical nitrogen reduction and preparation method thereof |
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| CN113235123A (en) * | 2021-04-06 | 2021-08-10 | 三峡大学 | Preparation method of defect graphene anchored double-transition metal monoatomic synthetic ammonia catalyst |
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| CN113215597A (en) * | 2021-04-06 | 2021-08-06 | 三峡大学 | Preparation method of defective foam graphene loaded transition metal monatomic catalyst |
| CN113235123A (en) * | 2021-04-06 | 2021-08-10 | 三峡大学 | Preparation method of defect graphene anchored double-transition metal monoatomic synthetic ammonia catalyst |
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| CN113106470B (en) * | 2021-04-06 | 2024-05-03 | 宁波烯固数造电池科技有限公司 | Vanadium-doped titanium dioxide/graphene electrocatalyst suitable for electrochemical nitrogen reduction and preparation method thereof |
| CN114752952A (en) * | 2022-04-14 | 2022-07-15 | 浙江大学 | Electrocatalytic nitrogen fixation device and method for simultaneously generating nitric acid and ammonia double products |
| CN115142079A (en) * | 2022-07-06 | 2022-10-04 | 中国华能集团清洁能源技术研究院有限公司 | Double functions of ammonia production and hydrogen production Electrolysis method and system |
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