阅读说明：本技术 一种Cu掺杂富氮多孔碳空心球的CO2还原催化剂及其制法 (CO of Cu-doped nitrogen-rich porous carbon hollow sphere2Reduction catalyst and process for producing the same ) 是由 孙海燕 于 2020-12-16 设计创作，主要内容包括：本发明涉及电催化还原CO-2技术领域,且公开了一种Cu掺杂富氮多孔碳空心球的CO-2还原催化剂,CaCO-3-蒽油-聚多巴胺复合物经过热活化、碳化,得到碳包覆结构,形成氮掺杂梯级多孔碳网络,得到Cu掺杂富氮多孔碳空心球的CO-2还原催化剂,呈纳米空心微球状,材料内部碳层交联,具有蜂窝状多孔结构,N元素掺杂造成碳层缺陷,表面呈褶皱状,N大多以吡啶N和吡咯N的形式存在,有利于还原CO-2,Cu掺杂使复合材料的法拉第效率增加,加速电子传输,增加气液接触面积,暴露更多的活性位点,提高了电催化还原CO-2的动力学速度、释放CO的速度,实现了更加优异的电催化还原CO-2性能。(The invention relates to the electrocatalytic reduction of CO 2 The technical field of the method and the device and discloses CO of the Cu-doped nitrogen-rich porous carbon hollow sphere 2 Reduction catalyst, CaCO 3 Thermal activation and carbonization are carried out on the anthracene oil-polydopamine composite to obtain a carbon coating structure, a nitrogen-doped cascade porous carbon network is formed, and CO of the Cu-doped nitrogen-rich porous carbon hollow sphere is obtained 2 The reduction catalyst is in a nano hollow microspherical shape, carbon layers in the material are crosslinked, the reduction catalyst has a honeycomb porous structure, the carbon layer defects are caused by doping of N elements, the surface is in a wrinkle shape, N mostly exists in the form of pyridine N and pyrrole N, and reduction of CO is facilitated 2 Cu doping increases the Faraday efficiency of the composite material, accelerates electron transmission, increases the gas-liquid contact area, exposes more active sites, and improves the electrocatalytic reduction of CO 2 The dynamic speed and the CO release speed of the catalyst realize more excellent electro-catalytic reduction of CO 2 And (4) performance.)

1. CO of Cu-doped nitrogen-rich porous carbon hollow sphere₂A reductive catalyst, characterized by: CO of the Cu-doped nitrogen-rich porous carbon hollow sphere₂The preparation method of the reduction catalyst comprises the following steps:

(1) adding anthracene oil fraction, nano calcium carbonate template agent, dopamine hydrochloride and copper sulfate into tetrahydrofuran, ultrasonically dispersing uniformly, stirring for 2-4h in a water bath at the constant temperature of 35-45 ℃, filtering and drying to obtain a precursor;

(2) fully grinding the precursor, placing the obtained powder in an atmosphere tube furnace, firstly carrying out a thermal activation process, then carrying out a carbonization process, and cooling to obtain a solid product;

(3) putting the solid product into a water bath device, carrying out water bath in hydrochloric acid solution at the temperature of 70-90 ℃, stirring at constant temperature for 1-3h, filtering, washing and drying to obtain CO of the Cu-doped nitrogen-rich porous carbon hollow sphere₂The catalyst is reduced.

2. CO of the Cu-doped nitrogen-rich porous carbon hollow sphere according to claim 1₂Reduction catalystThe method is characterized in that: the mass ratio of the anthracene oil fraction, the nano calcium carbonate template agent, the dopamine hydrochloride and the copper sulfate in the step (1) is 100:80-120:150-250: 15-40.

3. CO of the Cu-doped nitrogen-rich porous carbon hollow sphere according to claim 1₂A reductive catalyst, characterized by: the heat activation process in the step (2) is to heat up to 200-300 ℃ at a heating rate of 2 ℃/min in an air atmosphere, and to perform heat activation for 1-3 h.

4. CO of the Cu-doped nitrogen-rich porous carbon hollow sphere according to claim 1₂A reductive catalyst, characterized by: the carbonization process in the step (2) is to heat up to 650-750 ℃ at the heating rate of 5 ℃/min in the nitrogen atmosphere and to carbonize for 1-3 h.

5. CO of the Cu-doped nitrogen-rich porous carbon hollow sphere according to claim 1₂A reductive catalyst, characterized by: the water bath device in the step (3) comprises a main body, wherein the bottom of the main body is movably connected with a motor, the middle of the main body is movably connected with a partition plate, the middle of the partition plate is movably connected with a first gear, the top of the motor is movably connected with a second gear, the left side of the second gear is movably connected with a third gear, the bottom of the second gear is movably connected with a connecting rod, the top of the third gear is movably connected with a magnet, the top of the first gear is movably connected with a cross rod, the middle of the main body is movably connected with a bottom plate.

Technical Field

The invention relates to the electrocatalytic reduction of CO₂The technical field, in particular to CO of a Cu-doped nitrogen-rich porous carbon hollow sphere₂A reduction catalyst and a method for preparing the same.

Background

Since the twentieth century, the global environment has suddenly changed, the energy crisis has become more serious, and the air pollution has also become more serious, so that people hope to find a sustainable and promising energy conversion technology, and the problems of environment, energy and air pollution are mostly caused by a large amount of CO₂Due to the emission, scientists are looking for CO in order to cope with the problems of energy shortage and global warming₂Breakthrough of conversion technology, e.g. CO₂Synthetic chemistry of (1), electrocatalytic reduction of CO₂Photocatalytic reduction of CO₂And the like.

Electrocatalytic reduction of CO₂Intermittent renewable power storage and CO can be simultaneously realized₂An efficient way of converting, CO can be converted₂Conversion to CO, HCOOH, CH₄The CO is an energy product with a great application prospect and can be directly used for producing methanol by gas-liquid conversion and industrial hydrogenation, but the CO is an added value product₂The molecule has stable C ═ O bond and competitive hydrogen evolution reaction, so that the reduction of the molecule faces huge challenge, and therefore an effective catalyst is needed, and the electrocatalytic reduction of CO is improved₂The activity and the inhibition of hydrogen evolution reaction can keep excellent stability and selectivity to deal with the electrocatalytic reduction of CO₂The challenge of (2).

Cu is unique in various metal catalysts and can be used for electrocatalytic reduction of CO₂In addition, metal has ultrahigh surface energy in the synthesis process, is easy to agglomerate, and damages catalytic active sites to a great extent, while carbon material can well solve the problems of dispersion and stability of metal particles, so that the CO of the Cu-doped nitrogen-rich porous carbon hollow sphere is adopted₂In order to solve the above problems.

Technical problem to be solved

Aiming at the defects of the prior art, the invention provides CO of a Cu-doped nitrogen-rich porous carbon hollow sphere₂The reduction catalyst and the preparation method thereof solve the problem of the electrocatalytic reduction of CO by the carbon-based electrocatalyst₂The efficiency is low.

(II) technical scheme

In order to achieve the purpose, the invention provides the following technical scheme: CO of Cu-doped nitrogen-rich porous carbon hollow sphere₂Reduction catalyst, CO of said Cu doped nitrogen-rich porous carbon hollow sphere₂The preparation method of the reduction catalyst comprises the following steps:

(1) adding tetrahydrofuran, anthracene oil fraction, nano calcium carbonate template agent, dopamine hydrochloride and copper sulfate into a reaction bottle, ultrasonically dispersing uniformly, stirring for 2-4h in a water bath at the constant temperature of 35-45 ℃, filtering and drying to obtain a precursor;

(2) fully grinding the precursor, placing the obtained powder in an atmosphere tube furnace, firstly carrying out a thermal activation process, then carrying out a carbonization process, and cooling to obtain a solid product;

(3) putting the solid product into a water bath device, carrying out water bath in hydrochloric acid solution at the temperature of 70-90 ℃, stirring at constant temperature for 1-3h, filtering, washing and drying to obtain CO of the Cu-doped nitrogen-rich porous carbon hollow sphere₂The catalyst is reduced.

Preferably, the mass ratio of the anthracene oil fraction, the nano calcium carbonate template agent, the dopamine hydrochloride and the copper sulfate in the step (1) is 100:80-120:150-250: 15-40.

Preferably, the thermal activation process in the step (2) is to heat up to 200-300 ℃ at a heating rate of 2 ℃/min in an air atmosphere, and perform thermal activation for 1-3 h.

Preferably, the carbonization process in the step (2) is to heat up to 650-750 ℃ at a heating rate of 5 ℃/min in a nitrogen atmosphere, and to carbonize for 1-3 h.

Preferably, the water bath device in the step (3) comprises a main body, a motor is movably connected to the bottom of the main body, a partition plate is movably connected to the middle of the main body, a first gear is movably connected to the middle of the partition plate, a second gear is movably connected to the top of the motor, a third gear is movably connected to the left side of the second gear, a connecting rod is movably connected to the bottom of the second gear, a magnet is movably connected to the top of the third gear, a cross rod is movably connected to the top of the first gear, a bottom plate is movably connected to the middle of the main body, and a.

(III) advantageous technical effects

Compared with the prior art, the invention has the following beneficial technical effects:

CO of the Cu-doped nitrogen-rich porous carbon hollow sphere₂Reducing catalyst, using nano calcium carbonate as template agent, anthracene oil fraction as carbon source, copper sulfate as copper source and dopamine hydrochloride as nitrogen source, making dopamine hydrochloride undergo the process of self-polymerization on the surface of nano calcium carbonate to form CaCO₃The anthracene oil-polydopamine composite is subjected to thermal activation and high-temperature carbonization to obtain a carbon-coated structure, and CaCO₃Occupation of solid CaO, a pyrolysis productAnd stacking one on top of the other creates a large number of mesopores while the other product, CO₂The physical activation and CaO induced self-activation generate a large number of micropores to form a nitrogen-doped cascade porous carbon network, so that the specific surface area is increased, the catalytic active sites are increased, and the prepared CaCO₃The appearance of the-anthracene oil-polydopamine composite maintains the sphere-like shape of the template agent nano calcium carbonate, the nano calcium carbonate is mutually adhered, the surface is uneven, and the CO of the Cu-doped nitrogen-rich porous carbon hollow sphere is removed by acid cleaning to obtain the CO of the Cu-doped nitrogen-rich porous carbon hollow sphere₂The reduction catalyst is in a nano hollow microspherical shape, and is in a uniform grape-shaped microscopic shape as a whole, pore channels are communicated with each other, carbon layers in the material are crosslinked, and the reduction catalyst has a honeycomb porous structure, so that the specific surface area is further increased.

CO of the Cu-doped nitrogen-rich porous carbon hollow sphere₂The catalyst is reduced, N element is doped into the carbon skeleton, so that the carbon layer defect is caused, the surface of the carbon layer is wrinkled, the specific surface area is increased, and meanwhile, the N element mostly exists in the form of pyridine N and pyrrole N, so that the electrocatalytic reduction of CO is facilitated₂The doping of Cu increases the Faraday efficiency of the composite material, maintains the surface pore structure of the carbon material, accelerates the transmission of electrons, increases the gas-liquid contact area, exposes more active sites, reduces the moderate binding energy of Cu to intermediate products, and improves the electrocatalytic reduction of CO₂The kinetic speed and the CO release speed of the catalyst can enhance the selectivity of products CO, and meanwhile, the surface CO can be reduced by the Cu metal active sites^*The stability of the intermediate is beneficial to the release of CO, and more excellent electro-catalytic reduction of CO is realized₂And (4) performance.

Drawings

FIG. 1 is a front sectional structural schematic view of a water bath apparatus;

fig. 2 is a schematic view of a gear transmission structure.

1. A main body; 2. a motor; 3. a partition plate; 4. a first gear; 5. a second gear; 6. a third gear; 7. a connecting rod; 8. a magnet; 9. a cross bar; 10. a base plate; 11. and (4) a beaker.

Detailed Description

To achieve the above object, the present invention provides the followingDetailed description and examples: CO of Cu-doped nitrogen-rich porous carbon hollow sphere₂Reduction catalyst, CO of Cu doped nitrogen-rich porous carbon hollow sphere₂The preparation method of the reduction catalyst comprises the following steps:

(1) adding tetrahydrofuran, anthracene oil fraction, nano calcium carbonate template agent, dopamine hydrochloride and copper sulfate into a reaction bottle, wherein the mass ratio of the tetrahydrofuran to the anthracene oil fraction to the nano calcium carbonate template agent is 100:80-120:150, carrying out uniform ultrasonic dispersion, stirring for 2-4h in a water bath at 35-45 ℃, filtering and drying to obtain a precursor;

(2) fully grinding the precursor, placing the obtained powder in an atmosphere tube furnace, firstly carrying out a thermal activation process, wherein the thermal activation process is to heat up to 200-750 ℃ at a heating rate of 2 ℃/min in an air atmosphere, carrying out thermal activation for 1-3h, then carrying out a carbonization process, the carbonization process is to heat up to 650-750 ℃ at a heating rate of 5 ℃/min in a nitrogen atmosphere, carbonizing for 1-3h, and cooling to obtain a solid product;

(3) arrange the solid product in water bath device, water bath device includes the main part, the bottom swing joint of main part has the motor, the middle swing joint of main part has the baffle, the middle swing joint of baffle has gear one, the top swing joint of motor has gear two, the left side swing joint of gear two has gear three, the bottom swing joint of gear two has the connecting rod, the top swing joint of gear three has magnet, the top swing joint of gear one has the horizontal pole, the middle swing joint of main part has the bottom plate, the top swing joint of bottom plate has the beaker, water bath in 70-90 ℃ hydrochloric acid solution, the constant temperature stirring 1-3h, filter, wash and dry, obtain the CO of Cu doping nitrogen-enriched porous carbon hollow ball₂The catalyst is reduced.

Example 1

(1) Adding tetrahydrofuran, anthracene oil fraction, nano calcium carbonate template agent, dopamine hydrochloride and copper sulfate into a reaction bottle, wherein the mass ratio of the tetrahydrofuran to the anthracene oil fraction to the nano calcium carbonate template agent is 100:80:150:15, ultrasonically dispersing uniformly, stirring for 2 hours in a water bath at the constant temperature of 35 ℃, filtering and drying to obtain a precursor;

(2) fully grinding the precursor, placing the obtained powder in an atmosphere tube furnace, firstly carrying out a thermal activation process, wherein the thermal activation process is to heat up to 200 ℃ at a heating rate of 2 ℃/min in an air atmosphere, thermally activate for 1h, and then carrying out a carbonization process, the carbonization process is to heat up to 650 ℃ at a heating rate of 5 ℃/min in a nitrogen atmosphere, carbonize for 1h, and cool to obtain a solid product;

(3) arrange the solid product in water bath device, water bath device includes the main part, the bottom swing joint of main part has the motor, the middle swing joint of main part has the baffle, the middle swing joint of baffle has gear one, the top swing joint of motor has gear two, the left side swing joint of gear two has gear three, the bottom swing joint of gear two has the connecting rod, the top swing joint of gear three has magnet, the top swing joint of gear one has the horizontal pole, the middle swing joint of main part has the bottom plate, the top swing joint of bottom plate has the beaker, water bath in 70 ℃ hydrochloric acid solution, constant temperature stirring 1h, filter, wash and dry, obtain the CO of Cu doping nitrogen-enriched porous carbon hollow ball₂The catalyst is reduced.

Example 2

(1) Adding tetrahydrofuran, anthracene oil fraction, nano calcium carbonate template agent, dopamine hydrochloride and copper sulfate into a reaction bottle, wherein the mass ratio of the tetrahydrofuran to the anthracene oil fraction to the nano calcium carbonate template agent to the dopamine hydrochloride to the copper sulfate is 100:100:200:27.5, uniformly dispersing by ultrasonic, stirring for 3 hours in a water bath at the temperature of 40 ℃, filtering and drying to obtain a precursor;

(2) fully grinding the precursor, placing the obtained powder in an atmosphere tube furnace, firstly carrying out a thermal activation process, wherein the thermal activation process is to heat up to 250 ℃ at a heating rate of 2 ℃/min in an air atmosphere, thermally activate for 2h, and then carrying out a carbonization process, the carbonization process is to heat up to 700 ℃ at a heating rate of 5 ℃/min in a nitrogen atmosphere, carbonize for 2h, and cool to obtain a solid product;

(3) arrange the solid product in water bath device, water bath device includes the main part, the bottom swing joint of main part has the motor, the middle swing joint of main part has the baffle, the middle swing joint of baffle has gear one, the top swing joint of motor has gear two, the left side swing joint of gear two has gear three, the bottom swing joint of gear two has the connecting rod, the top swing joint of gear three has magnet, the top swing joint of gear one has the horizontal pole, the middle swing joint of main part has the horizontal poleConnecting with a bottom plate, movably connecting with a beaker at the top of the bottom plate, water-bathing in 80 deg.C hydrochloric acid solution, stirring at constant temperature for 2h, filtering, washing and drying to obtain CO doped with Cu nitrogen-rich porous carbon hollow sphere₂The catalyst is reduced.

Example 3

(1) Adding tetrahydrofuran, anthracene oil fraction, nano calcium carbonate template agent, dopamine hydrochloride and copper sulfate into a reaction bottle in a mass ratio of 100:90:190:20, ultrasonically dispersing uniformly, stirring for 4 hours in a water bath at 35 ℃, filtering and drying to obtain a precursor;

(2) fully grinding the precursor, placing the obtained powder in an atmosphere tube furnace, firstly carrying out a thermal activation process, wherein the thermal activation process is to heat up to 260 ℃ at a heating rate of 2 ℃/min in an air atmosphere, thermally activate for 3h, and then carrying out a carbonization process, the carbonization process is to heat up to 690 ℃ at a heating rate of 5 ℃/min in a nitrogen atmosphere, carbonize for 1h, and cool to obtain a solid product;

(3) arrange the solid product in water bath device, water bath device includes the main part, the bottom swing joint of main part has the motor, the middle swing joint of main part has the baffle, the middle swing joint of baffle has gear one, the top swing joint of motor has gear two, the left side swing joint of gear two has gear three, the bottom swing joint of gear two has the connecting rod, the top swing joint of gear three has magnet, the top swing joint of gear one has the horizontal pole, the middle swing joint of main part has the bottom plate, the top swing joint of bottom plate has the beaker, water bath in 75 ℃ hydrochloric acid solution, constant temperature stirring 3h, filter, wash and dry, obtain the CO of Cu doping nitrogen-enriched porous carbon hollow ball₂The catalyst is reduced.

Example 4

(1) Adding tetrahydrofuran, anthracene oil fraction, nano calcium carbonate template agent, dopamine hydrochloride and copper sulfate into a reaction bottle, wherein the mass ratio of the tetrahydrofuran to the anthracene oil fraction to the nano calcium carbonate template agent is 100:120:250:40, ultrasonically dispersing uniformly, stirring for 4 hours at constant temperature in a water bath at 45 ℃, filtering and drying to obtain a precursor;

(2) fully grinding the precursor, placing the obtained powder in an atmosphere tube furnace, firstly carrying out a thermal activation process, wherein the thermal activation process is to heat up to 300 ℃ at a heating rate of 2 ℃/min in an air atmosphere, thermally activate for 3h, and then carrying out a carbonization process, the carbonization process is to heat up to 750 ℃ at a heating rate of 5 ℃/min in a nitrogen atmosphere, carbonize for 3h, and cool to obtain a solid product;

(3) arrange the solid product in water bath device, water bath device includes the main part, the bottom swing joint of main part has the motor, the middle swing joint of main part has the baffle, the middle swing joint of baffle has gear one, the top swing joint of motor has gear two, the left side swing joint of gear two has gear three, the bottom swing joint of gear two has the connecting rod, the top swing joint of gear three has magnet, the top swing joint of gear one has the horizontal pole, the middle swing joint of main part has the bottom plate, the top swing joint of bottom plate has the beaker, water bath in 90 ℃ hydrochloric acid solution, constant temperature stirring 3h, filter, wash and dry, obtain the CO of Cu doping nitrogen-enriched porous carbon hollow ball₂The catalyst is reduced.

Comparative example 1

(1) Adding tetrahydrofuran, anthracene oil fraction, nano calcium carbonate template agent, dopamine hydrochloride and copper sulfate into a reaction bottle, wherein the mass ratio of the tetrahydrofuran to the anthracene oil fraction to the nano calcium carbonate template agent is 100:60:120:10, ultrasonically dispersing uniformly, stirring for 2 hours at constant temperature in a water bath at 45 ℃, filtering and drying to obtain a precursor;

(2) fully grinding the precursor, placing the obtained powder in an atmosphere tube furnace, firstly carrying out a thermal activation process, wherein the thermal activation process is to heat up to 300 ℃ at a heating rate of 2 ℃/min in an air atmosphere, thermally activate for 1h, and then carrying out a carbonization process, the carbonization process is to heat up to 750 ℃ at a heating rate of 5 ℃/min in a nitrogen atmosphere, carbonize for 1h, and cool to obtain a solid product;

(3) arrange the solid product in water bath device, water bath device includes the main part, the bottom swing joint of main part has the motor, the middle swing joint of main part has the baffle, the middle swing joint of baffle has gear one, the top swing joint of motor has gear two, the left side swing joint of gear two has gear three, the bottom swing joint of gear two has the connecting rod, the top swing joint of gear three has magnet, the top swing joint of gear one has violentlyA bottom plate is movably connected in the middle of the main body, a beaker is movably connected at the top of the bottom plate, the mixture is subjected to water bath in 90 ℃ hydrochloric acid solution, the mixture is stirred for 1 hour at constant temperature, and the mixture is filtered, washed and dried to obtain CO of the Cu-doped nitrogen-rich porous carbon hollow sphere₂The catalyst is reduced.

1mL of ethanol, and CO of the Cu-doped nitrogen-rich porous carbon hollow sphere obtained in the example and the comparative example are added into a reaction bottle₂Reducing catalyst 10mg and carbon black 10mg, adding 100uL of Nafion solution with the mass fraction of 5%, uniformly dispersing by ultrasonic, coating 100uL on the surface of carbon paper, drying, using Pt as a counter electrode, Ag/AgCl as a reference electrode, and 0.1mol/L electrolyte of KHCO₃Solution, CO Using electrochemical workstation model CHI 660E₂And (5) testing electrochemical reduction performance.