Carbon material and preparation method and application thereof
By using lignin and cellulose as precursors and incorporating nitrogen, phosphorus, and iron ions through pyrolysis to prepare carbon materials, the problem of slow oxygen reduction reaction at the cathode of fuel cells was solved, achieving efficient and stable electrocatalytic performance and resistance to methanol interference, making it suitable for fuel cell catalysts.
Patent Information
- Application Number
- CN202410558539.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-06
- Publication Date
- 2025-11-07
AI Technical Summary
The oxygen reduction reaction kinetics at the cathode of existing fuel cells are slow and require a large amount of platinum-based catalysts, resulting in scarce reserves and high prices, which hinders the commercial application of fuel cells.
Using lignin and cellulose as precursors, and incorporating nitrogen, phosphorus, and iron ions, carbon materials with large specific surface area and excellent electrocatalytic performance are prepared by pyrolysis in a nitrogen atmosphere and used as catalysts in electrocatalytic oxygen reduction reactions.
The preparation process is simple, the raw materials are widely available and renewable, and the carbon materials have long-term stability and resistance to methanol interference, making them suitable for mass production.
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Figure CN120914264A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present disclosure relates to the technical field of fuel cell catalysts, and in particular to a carbon material and a preparation method and application thereof. BACKGROUND
[0002] The development of society cannot be separated from the driving of energy, however, the reserves of non-renewable energy such as coal, oil and natural gas are gradually decreasing, at the same time, the consumption of fossil fuels in industry and daily life has caused serious energy shortage and environmental problems, forcing human society to find more efficient and clean energy supply, which prompts people to develop green and efficient new energy to replace traditional non-renewable energy. Therefore, exploring green and efficient new energy has attracted widespread attention in society.
[0003] Among many green energies, fuel cells have broad application prospects in new energy electric vehicles and mobile devices due to their high energy density, environmental friendliness, safety and reliability. However, due to the slow kinetics process of the cathode oxygen reduction reaction (ORR) of the fuel cell, a large amount of platinum-based catalyst needs to be loaded on the cathode to accelerate the cathode reaction. The scarcity of platinum in nature and its high price hinder the large-scale commercial application of fuel cells. SUMMARY
[0004] (I) Technical problems to be solved
[0005] To solve at least one of the above technical problems in the prior art, embodiments of the present disclosure provide a carbon material and a preparation method and application thereof, in which lignin and cellulose are used as precursors, nitrogen, phosphorus and iron ions are doped, and pyrolysis is carried out in a nitrogen atmosphere, so that the obtained carbon material has a large specific surface area, excellent electrocatalytic performance, long-term stability and methanol resistance, and the catalyst preparation process is simple.
[0006] (II) Technical solutions
[0007] In view of the above problems, embodiments of the present disclosure provide a carbon material and a preparation method and application thereof.
[0008] According to a first aspect of the present disclosure, a preparation method of a carbon material is provided, comprising the following steps: dissolving lignin and cellulose in a mixed solution of ethanol and water to obtain a first mixed solution; adding citric acid to the first mixed solution to obtain a second mixed solution; adding a soluble iron salt to the second mixed solution, stirring, washing and drying to obtain a first powder; and obtaining a target powder, grinding and calcining the target powder to obtain the carbon material, wherein the target powder comprises the first powder.
[0009] In some example embodiments, before the target powder is obtained, the method further comprises the following steps: dissolving the phytic acid, the lignin and the cellulose in water, stirring to obtain a third mixed solution; washing the third mixed solution by suction filtration to obtain a first product; and freezing the first product, and freeze-drying the frozen first product to obtain a polymerization product of the phytic acid and the melamine, and the target powder is obtained by mixing the polymerization product of the phytic acid and the melamine with the first powder.
[0010] In some example embodiments, in the step of grinding and calcining the target powder, the equipment used in the calcination process comprises a tube furnace; and / or, the temperature of the calcination is 700-1000 DEG C; and / or, the time of the calcination is 1-4 hours.
[0011] In some example embodiments, in the step of grinding and calcining the target powder, the calcination process is carried out under the protection of a protective gas.
[0012] In some example embodiments, the protective gas comprises nitrogen.
[0013] In some example embodiments, the lignin and the cellulose are obtained from biomass.
[0014] In some example embodiments, the biomass comprises at least one of pear wood, apple wood, jujube wood, peach wood, apricot shell, walnut shell and cotton stalk.
[0015] In some example embodiments, the soluble iron salt comprises at least one of ferric chloride, ferric nitrate and ferric sulfate.
[0016] The second aspect of the present disclosure provides a carbon material prepared by the above method.
[0017] The third aspect of the present disclosure further provides an application of the carbon material prepared by the above method, which is applied as a catalyst in an electrocatalytic oxygen reduction reaction.
[0018] (III) Beneficial Effects
[0019] From the above technical solutions, it can be seen that the carbon material and the preparation method and application thereof provided by the embodiments of the present disclosure at least have one of the following beneficial effects:
[0020] (1) The raw materials lignin and cellulose of the embodiments of the present disclosure are obtained from biomass, and the raw materials are widely sourced and renewable.
[0021] (2) The carbon material provided by the embodiments of the present disclosure has a large specific surface area, and the iron phosphide is uniformly dispersed. The synergistic effect of the nitrogen and phosphorus heteroatoms and the iron phosphide sites makes the electrocatalytic performance excellent, has long-term stability and anti-methanol interference ability.
[0022] (3) The preparation method of the carbon material provided by the embodiments of the present disclosure is simple in operation, low in cost, and suitable for mass production. BRIEF DESCRIPTION OF DRAWINGS
[0023] The above and other objects, features and advantages of the present disclosure will become more apparent from the following description when taken in conjunction with the accompanying drawings, in which:
[0024] Figure 1 A flowchart schematically showing a preparation method of a carbon material according to an embodiment of the present disclosure is shown.
[0025] Figure 2 A transmission electron microscope (TEM) image of a carbon material prepared according to Example 6 of the present disclosure is schematically shown.
[0026] Figure 3 A transmission electron microscope (TEM) image of a carbon material prepared according to Example 16 of the present disclosure is schematically shown.
[0027] Figure 4 A plot of current density versus potential of a carbon material prepared according to Example 6 of the present disclosure is schematically shown.
[0028] Figure 5 X-ray diffraction (XRD) patterns of carbon materials prepared according to Examples 16, 17 and 18 of the present disclosure are schematically shown.
[0029] Figure 6 A plot of current density versus potential of a carbon material prepared according to Example 16 of the present disclosure is schematically shown. DETAILED DESCRIPTION
[0030] For the purpose of making the objects, technical solutions and advantages of the present disclosure clearer, the present disclosure will be further described in detail below with reference to specific embodiments and drawings. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present disclosure.
[0031] Figure 1 A flowchart schematically showing a preparation method of a carbon material according to an embodiment of the present disclosure is shown.
[0032] As Figure 1 shown, the preparation method of the carbon material according to the embodiments of the present disclosure includes steps S110-S140.
[0033] In step S110, lignin and cellulose are dissolved in a mixed solution of ethanol and water to obtain a first mixed solution. Optionally, the lignin and cellulose are obtained from biomass. The biomass includes at least one of pear wood, apple wood, jujube wood, peach wood, apricot shell, walnut shell, and cotton stalk.
[0034] In step S120, citric acid is added to the first mixed solution to obtain a second mixed solution.
[0035] In step S130, a soluble iron salt is added to the second mixed solution, stirred, washed, and dried to obtain a first powder. Optionally, the soluble iron salt includes at least one of ferric chloride, ferric nitrate, and ferric sulfate, and the drying temperature is 80°C.
[0036] In step S140, a target powder is obtained, and the target powder is ground and calcined to obtain a carbon material, wherein the target powder includes the first powder.
[0037] In some example embodiments, before the target powder is obtained, the method further includes the following steps: dissolving phytic acid and lignin and cellulose in water, stirring to obtain a third mixed solution; washing the third mixed solution by suction filtration to obtain a first product; and freezing the first product, and freeze-drying the frozen first product to obtain a polymerization product of phytic acid and melamine. Meanwhile, obtaining the target powder includes the following steps: mixing the polymerization product of phytic acid and melamine and the first powder to obtain the target powder.
[0038] When the target powder is the first powder, the obtained carbon material is a carbon material with iron loaded on lignin and cellulose. When the target powder is a mixed powder of the polymerization product of phytic acid and melamine and the first powder, the obtained carbon material with iron phosphide loaded on lignin and cellulose has a porous structure, and due to the presence of nitrogen elements, the final obtained carbon material is a nitrogen and phosphorus co-doped porous carbon material with iron phosphide loaded on lignin and cellulose, which has a large specific surface area and excellent catalytic performance.
[0039] For example: Dissolve phytic acid and lignin and cellulose in water, stir uniformly at room temperature, wash the mixed solution by suction filtration, freeze in a refrigerator for 12 hours, and then freeze-dry in a freeze dryer to obtain a polymerization product of phytic acid and melamine (PMSA).
[0040] In some example embodiments, in the step of grinding and calcining the target powder, the equipment used in the calcination process includes a tube furnace. Optionally, the calcination temperature is 700°C-1000°C. Optionally, the calcination time is 1h-4h. Optionally, the calcination process is carried out under the protection of a protective gas, and the protective gas includes nitrogen.
[0041] For example, the target powder obtained by mixing the polymerization product of phytic acid and melamine and the first powder is ground for 30 minutes, placed in a tube furnace, calcined at 800 DEG C for 3h under nitrogen protection, to obtain a porous carbon material loaded with phosphorus iron on nitrogen-phosphorus co-doped lignin and cellulose.
[0042] The porous carbon material loaded with phosphorus iron on nitrogen-phosphorus co-doped lignin and cellulose prepared according to the embodiments of the present disclosure has a large specific surface area, and transition metal is uniformly dispersed. The phosphorus iron nanoparticles synergize with active sites in the N and P doped carbon structure, so that the electrocatalytic performance is excellent, has long-term stability and anti-methanol interference ability, and can be applied as a catalyst in the electrocatalytic oxygen reduction reaction.
[0043] The lignin and cellulose loaded with phosphorus iron on carbon material, the preparation method and application thereof provided by the embodiments of the present disclosure will be described in detail below in conjunction with examples, but they should not be understood as limiting the scope of protection of the present disclosure.
[0044] Example 1
[0045] In step S1, the lignin and cellulose are dissolved in a mixed solution of ethanol and water, a preset mass of citric acid is added to the solution, and after being fully mixed, a preset mass of iron nitrate nonahydrate is added thereto, and stirred at room temperature for 15 minutes. Then, the mixed solution is washed and dried at 80 DEG C to obtain a first powder.
[0046] In step S2, the first powder obtained in step S1 is ground for 30 minutes, placed in a tube furnace, and calcined at 800 DEG C for 2h under nitrogen protection to obtain a carbon material loaded with iron on lignin and cellulose.
[0047] Example 2
[0048] In step S1, the lignin and cellulose are dissolved in a mixed solution of ethanol and water, a preset mass of citric acid is added to the solution, and after being fully mixed, a preset mass of iron nitrate nonahydrate is added thereto, and stirred at room temperature for 15 minutes. Then, the mixed solution is washed and dried at 80 DEG C to obtain a first powder.
[0049] In step S2, the first powder obtained in step S1 is ground for 30 minutes, placed in a tube furnace, and calcined at 800 DEG C for 2h under nitrogen protection to obtain a carbon material loaded with iron on lignin and cellulose.
[0050] Example 3
[0051] In step S1, the lignin and cellulose are dissolved in a mixed solution of ethanol and water, a preset mass of citric acid is added to the solution, and after being fully mixed, a preset mass of iron nitrate nonahydrate is added thereto, and stirred at room temperature for 15 minutes. Then, the mixed solution is washed and dried at 80 DEG C to obtain a first powder.
[0052] In step S2, the first powder obtained in step S1 is ground for 30 minutes, placed in a tube furnace, calcined at 700 DEG C for 1h under nitrogen protection, to obtain a carbon material with iron loaded on lignin and cellulose.
[0053] Example 4
[0054] In step S1, lignin and cellulose are dissolved in a mixed solution of ethanol and water, a preset mass of citric acid is added to the solution, a preset mass of ferric chloride is added after sufficient mixing, the molar ratio of iron element to carbon element is 1:5, and stirring is performed at room temperature for 15 minutes. The mixed solution is then washed and dried at 80 DEG C to obtain a first powder.
[0055] In step S2, the first powder obtained in step S1 is ground for 30 minutes, placed in a tube furnace, calcined at 1000 DEG C for 4h under nitrogen protection, to obtain a carbon material with iron loaded on lignin and cellulose.
[0056] Example 5
[0057] In step S1, lignin and cellulose are dissolved in a mixed solution of ethanol and water, a preset mass of citric acid is added to the solution, a preset mass of ferric chloride is added after sufficient mixing, the molar ratio of iron element to carbon element is 1:10, and stirring is performed at room temperature for 15 minutes. The mixed solution is then washed and dried at 80 DEG C to obtain a first powder.
[0058] In step S2, the first powder obtained in step S1 is ground for 30 minutes, placed in a tube furnace, calcined at 800 DEG C under nitrogen protection, to obtain a carbon material with iron loaded on lignin and cellulose.
[0059] Example 6
[0060] In step S1, lignin and cellulose are dissolved in a mixed solution of ethanol and water, a preset mass of citric acid is added to the solution, a preset mass of ferric chloride is added after sufficient mixing, the molar ratio of iron element to carbon element is 1:10, and stirring is performed at room temperature for 15 minutes. The mixed solution is then washed and dried at 80 DEG C to obtain a first powder.
[0061] In step S2, the first powder obtained in step S1 is ground for 30 minutes, placed in a tube furnace, calcined at 800 DEG C under nitrogen protection, to obtain a carbon material with iron loaded on lignin and cellulose.
[0062] Figure 2 A transmission electron microscope (TEM) image of the carbon material prepared according to Example 6 of the present disclosure is schematically shown.
[0063] As Figure 2 shown, the carbon material prepared according to Example 6 of the present disclosure has a uniform structure.
[0064] Figure 4 The diagram illustrates the curve of current density versus potential of the carbon material prepared according to Example 6 of this disclosure.
[0065] like Figure 4 As shown, the onset potential, half-wave potential, and limiting current density values of the carbon material prepared according to Example 6 of this disclosure all reflect the excellent catalytic performance of the material. Wherein, Fe1-PANI indicates a molar ratio of iron (Fe) to lignin and cellulose (PANI) of 1:1; Fe2-PANI indicates a molar ratio of iron (Fe) to lignin and cellulose (PANI) of 2:1; and Fe3-PANI indicates a molar ratio of iron (Fe) to lignin and cellulose (PANI) of 3:1.
[0066] Example 7
[0067] In step S1, phytic acid, lignin, and cellulose are dissolved in water and stirred evenly at room temperature. The mixed solution is filtered and washed, then frozen in a refrigerator for 12 hours, and finally freeze-dried in a freeze dryer to obtain the polymer product of phytic acid and melamine (PMSA).
[0068] In step S2, lignin and cellulose are dissolved in a mixed solution of ethanol and water. A predetermined amount of citric acid is added to the solution, and after thorough mixing, a predetermined amount of ferric chloride is added and stirred at room temperature for 12 hours. The mixed solution is then washed and dried at 80°C to obtain the first powder.
[0069] In step S3, the polymer product of phytic acid and melamine obtained in step S1 is mixed with the first powder obtained in step S2 at a mass ratio of 1:1, ground for 30 minutes, placed in a tube furnace, and calcined at 800°C under nitrogen protection to obtain a porous carbon material with nitrogen and phosphorus co-doped lignin and cellulose loaded with iron phosphide.
[0070] The order of steps S1 and S2 can be reversed.
[0071] Example 8
[0072] In step S1, phytic acid, lignin, and cellulose are dissolved in water and stirred evenly at room temperature. The mixed solution is filtered and washed, then frozen in a refrigerator for 12 hours, and finally freeze-dried in a freeze dryer to obtain the polymer product of phytic acid and melamine (PMSA).
[0073] In step S2, lignin and cellulose are dissolved in a mixed solution of ethanol and water. A predetermined amount of citric acid is added to the solution, and after thorough mixing, a predetermined amount of ferric chloride is added and stirred at room temperature for 24 hours. The mixed solution is then washed and dried at 80°C to obtain the first powder.
[0074] In step S3, the polymerization product of phytic acid and melamine obtained in step S1 is mixed with the first powder obtained in step S2 at a mass ratio of 1:1, ground for 30 minutes, placed in a tube furnace, calcined at 800°C under nitrogen protection, to obtain a porous carbon material loaded with phosphorus-doped iron phosphide on lignin and cellulose.
[0075] The order of steps S1 and S2 can be exchanged.
[0076] Example 9
[0077] In step S1, phytic acid, lignin and cellulose are dissolved in water, stirred uniformly at room temperature, the mixed solution is washed by suction filtration, placed in a refrigerator for 12 hours, and then freeze-dried in a freeze dryer to obtain a polymerization product of phytic acid and melamine (PMSA).
[0078] In step S2, lignin and cellulose are dissolved in a mixed solution of ethanol and water, a predetermined mass of citric acid is added to the solution, and a predetermined mass of ferric chloride is added after thorough mixing, and stirred at room temperature for 48 hours. The mixed solution is then washed and dried at 80°C to obtain a first powder.
[0079] In step S3, the polymerization product of phytic acid and melamine obtained in step S1 is mixed with the first powder obtained in step S2 at a mass ratio of 1:1, ground for 30 minutes, placed in a tube furnace, calcined at 800°C under nitrogen protection, to obtain a porous carbon material loaded with phosphorus-doped iron phosphide on lignin and cellulose.
[0080] The order of steps S1 and S2 can be exchanged.
[0081] Example 10
[0082] In step S1, phytic acid, lignin and cellulose are dissolved in water, stirred uniformly at room temperature, the mixed solution is washed by suction filtration, placed in a refrigerator for 12 hours, and then freeze-dried in a freeze dryer to obtain a polymerization product of phytic acid and melamine (PMSA).
[0083] In step S2, lignin and cellulose are dissolved in a mixed solution of ethanol and water, a predetermined mass of citric acid is added to the solution, and a predetermined mass of ferric chloride is added after thorough mixing, and stirred at room temperature for 24 hours. The mixed solution is then washed and dried at 80°C to obtain a first powder.
[0084] In step S3, the polymerization product of phytic acid and melamine obtained in step S1 is mixed with the first powder obtained in step S2 at a mass ratio of 1:2, ground for 30 minutes, placed in a tube furnace, calcined at 800°C under nitrogen protection, to obtain a porous carbon material loaded with phosphorus-doped iron phosphide on lignin and cellulose.
[0085] Wherein, the order of step S1 and step S2 can be exchanged.
[0086] Example 11
[0087] In step S1, the phytic acid, lignin and cellulose are dissolved in water, stirred uniformly at room temperature, the mixed solution is washed by suction filtration, put into the refrigerator for 12 hours, and then freeze-dried in a freeze dryer to obtain the polymerization product of phytic acid and melamine (PMSA).
[0088] In step S2, the lignin and cellulose are dissolved in a mixed solution of ethanol and water, a preset mass of citric acid is added to the solution, and after mixing, a preset mass of ferric chloride is added and stirred at room temperature for 24 hours. Then the mixed solution is washed and dried at 80°C to obtain a first powder.
[0089] In step S3, the polymerization product of phytic acid and melamine obtained in step S1 and the first powder obtained in step S2 are mixed in a mass ratio of 1:3, ground for 30 minutes, placed in a tube furnace, calcined at 800°C under nitrogen protection to obtain a porous carbon material loaded with phosphorus iron on nitrogen and phosphorus co-doped lignin and cellulose.
[0090] Wherein, the order of step S1 and step S2 can be exchanged.
[0091] Example 12
[0092] In step S1, the phytic acid, lignin and cellulose are dissolved in water, stirred uniformly at room temperature, the mixed solution is washed by suction filtration, put into the refrigerator for 12 hours, and then freeze-dried in a freeze dryer to obtain the polymerization product of phytic acid and melamine (PMSA).
[0093] In step S2, the lignin and cellulose are dissolved in a mixed solution of ethanol and water, a preset mass of citric acid is added to the solution, and after mixing, a preset mass of ferric chloride is added and stirred at room temperature for 24 hours. Then the mixed solution is washed and dried at 80°C to obtain a first powder.
[0094] In step S3, the polymerization product of phytic acid and melamine obtained in step S1 and the first powder obtained in step S2 are mixed in a mass ratio of 1:4, ground for 30 minutes, placed in a tube furnace, calcined at 800°C under nitrogen protection to obtain a porous carbon material loaded with phosphorus iron on nitrogen and phosphorus co-doped lignin and cellulose.
[0095] Wherein, the order of step S1 and step S2 can be exchanged.
[0096] Example 13
[0097] In step S1, phytic acid is dissolved with lignin and cellulose in water, stirred uniformly at room temperature, the mixed solution is washed by suction filtration, placed in a refrigerator for 12 hours, and then freeze-dried in a freeze dryer to obtain a polymerization product of phytic acid and melamine (PMSA).
[0098] In step S2, lignin and cellulose are dissolved in a mixed solution of ethanol and water, a preset mass of citric acid is added to the solution, and after being mixed thoroughly, a preset mass of ferric chloride is added, stirred at room temperature for 24 hours. Then the mixed solution is washed and dried at 80°C to obtain a first powder.
[0099] In step S3, the polymerization product of phytic acid and melamine obtained in step S1 is mixed with the first powder obtained in step S2 at a mass ratio of 1:5, ground for 30 minutes, placed in a tube furnace, calcined at 1000°C for 4h under nitrogen protection to obtain a porous carbon material loaded with phosphorus-doped iron phosphide on lignin and cellulose.
[0100] The order of step S1 and step S2 can be changed.
[0101] Example 14
[0102] In step S1, phytic acid is dissolved with lignin and cellulose in water, stirred uniformly at room temperature, the mixed solution is washed by suction filtration, placed in a refrigerator for 12 hours, and then freeze-dried in a freeze dryer to obtain a polymerization product of phytic acid and melamine (PMSA).
[0103] In step S2, lignin and cellulose are dissolved in a mixed solution of ethanol and water, a preset mass of citric acid is added to the solution, and after being mixed thoroughly, a preset mass of ferric chloride is added, stirred at room temperature for 24 hours. Then the mixed solution is washed and dried at 80°C to obtain a first powder.
[0104] In step S3, the polymerization product of phytic acid and melamine obtained in step S1 is mixed with the first powder obtained in step S2 at a mass ratio of 1:5, ground for 30 minutes, placed in a tube furnace, calcined at 1000°C for 4h under nitrogen protection to obtain a porous carbon material loaded with phosphorus-doped iron phosphide on lignin and cellulose.
[0105] The order of step S1 and step S2 can be changed.
[0106] Example 15
[0107] In step S1, phytic acid is dissolved with lignin and cellulose in water, stirred uniformly at room temperature, the mixed solution is washed by suction filtration, placed in a refrigerator for 12 hours, and then freeze-dried in a freeze dryer to obtain a polymerization product of phytic acid and melamine (PMSA).
[0108] In step S2, lignin and cellulose are dissolved in a mixed solution of ethanol and water, a preset mass of citric acid is added to the solution, and a preset mass of ferric chloride is added after thorough mixing, and stirred at room temperature for 24 hours. The mixed solution is then washed and dried at 80°C to obtain a first powder.
[0109] In step S3, the polymerization product of phytic acid and melamine obtained in step S1 is mixed with the first powder obtained in step S2 at a mass ratio of 1:4, ground for 30 minutes, placed in a tube furnace, and calcined at 900°C under nitrogen protection to obtain a porous carbon material loaded with phosphorus-doped iron phosphide on lignin and cellulose.
[0110] The order of steps S1 and S2 can be changed.
[0111] Example 16
[0112] In step S1, phytic acid is dissolved in water with lignin and cellulose, and stirred uniformly at room temperature. The mixed solution is filtered and washed, placed in a refrigerator for 12 hours, and then freeze-dried in a freeze dryer to obtain a polymerization product of phytic acid and melamine (PMSA).
[0113] In step S2, lignin and cellulose are dissolved in a mixed solution of ethanol and water, a preset mass of citric acid is added to the solution, and a preset mass of ferric chloride is added after thorough mixing, and stirred at room temperature for 24 hours. The mixed solution is then washed and dried at 80°C to obtain a first powder.
[0114] In step S3, the polymerization product of phytic acid and melamine obtained in step S1 is mixed with the first powder obtained in step S2 at a mass ratio of 1:4, ground for 30 minutes, placed in a tube furnace, and calcined at 800°C under nitrogen protection for 1 hour to obtain a porous carbon material loaded with phosphorus-doped iron phosphide on lignin and cellulose.
[0115] The order of steps S1 and S2 can be changed.
[0116] Figure 3 A transmission electron microscope (TEM) image of the carbon material prepared according to Example 16 of the present disclosure is schematically shown.
[0117] Figure 3 As shown, the carbon material prepared according to Example 16 of the present disclosure is a porous carbon material with a large specific surface area and uniform dispersion of nitrogen and phosphorus elements.
[0118] Figure 6 A plot of current density versus potential of the carbon material prepared according to Example 16 of the present disclosure is schematically shown.
[0119] As Figure 6As shown, the starting potential, half-wave potential and limiting current density values of the carbon material prepared according to Embodiment 16 of the present disclosure all reflect that the material has relatively excellent catalytic performance. Among them, Fe2-N1P3-PANI represents that the molar mass ratio of iron (Fe) element, nitrogen (N) element, phosphorus (P) element to lignin and cellulose (PANI) is 2:1:3:1; Fe2-N1P2-PANI represents that the molar mass ratio of iron (Fe) element, nitrogen (N) element, phosphorus (P) element to lignin and cellulose (PANI) is 2:1:2:1; Fe2-N1P1-PANI represents that the molar mass ratio of iron (Fe) element, nitrogen (N) element, phosphorus (P) element to lignin and cellulose (PANI) is 2:1:1:1.
[0120] Embodiment 17
[0121] In step S1, the phytic acid is dissolved in water with lignin and cellulose, stirred uniformly at room temperature, the mixed solution is washed by suction filtration, placed in a refrigerator for freezing for 12 hours, and then freeze-dried in a freeze dryer to obtain a polymerization product of phytic acid and melamine (PMSA).
[0122] In step S2, the lignin and cellulose are dissolved in a mixed solution of ethanol and water, a preset mass of citric acid is added to the solution, and after being fully mixed, a preset mass of ferric chloride is added thereto, and stirred at room temperature for 24 hours. Then the mixed solution is washed and dried at 80°C to obtain a first powder.
[0123] In step S3, the polymerization product of phytic acid and melamine obtained in step S1 is mixed with the first powder obtained in step S2 at a mass ratio of 1:4, ground for 30 minutes, placed in a tube furnace, calcined at 800°C for 2h under nitrogen protection to obtain a porous carbon material of nitrogen and phosphorus co-doped lignin and cellulose loaded with iron phosphide.
[0124] Among them, the order of step S1 and step S2 can be exchanged.
[0125] Embodiment 18
[0126] In step S1, the phytic acid is dissolved in water with lignin and cellulose, stirred uniformly at room temperature, the mixed solution is washed by suction filtration, placed in a refrigerator for freezing for 12 hours, and then freeze-dried in a freeze dryer to obtain a polymerization product of phytic acid and melamine (PMSA).
[0127] In step S2, the lignin and cellulose are dissolved in a mixed solution of ethanol and water, a preset mass of citric acid is added to the solution, and after being fully mixed, a preset mass of ferric chloride is added thereto, and stirred at room temperature for 24 hours. Then the mixed solution is washed and dried at 80°C to obtain a first powder.
[0128] In step S3, the polymer product of phytic acid and melamine obtained in step S1 is mixed with the first powder obtained in step S2 at a mass ratio of 1:4, ground for 30 minutes, placed in a tube furnace, and calcined at 800°C for 3 hours under nitrogen protection to obtain a porous carbon material with nitrogen and phosphorus co-doped lignin and cellulose loaded with iron phosphide.
[0129] The order of steps S1 and S2 can be reversed.
[0130] Figure 5 The X-ray diffraction (XRD) patterns of carbon materials prepared according to embodiments 16, 17 and 18 of this disclosure are shown schematically.
[0131] Depend on Figure 5 It can be seen that the carbon materials prepared according to Examples 16, 17 and 18 of this disclosure can match the standard diffraction peaks of Fe2P and FeP, indicating that the prepared porous carbon materials are loaded with iron phosphide.
[0132] Those skilled in the art will understand that the features described in the various embodiments of the present invention can be combined and / or combined in various ways, even if such combinations or combinations are not explicitly described in the present invention. In particular, the features described in the various embodiments of the present invention can be combined and / or combined in various ways without departing from the spirit and teachings of the present invention. All such combinations and / or combinations fall within the scope of the present invention.
[0133] The embodiments of the present invention have been described above. However, these embodiments are merely illustrative and not intended to limit the scope of the invention. Although various embodiments have been described above, this does not mean that the measures in the various embodiments cannot be used advantageously in combination. Various substitutions and modifications can be made by those skilled in the art without departing from the scope of the invention, and all such substitutions and modifications should fall within the scope of the invention.
Claims
1. A method for producing a carbon material, characterized by, The method comprises the following steps: dissolving lignin and cellulose in a mixed solution of ethanol and water to obtain a first mixed solution; adding citric acid to the first mixed solution to obtain a second mixed solution; adding a soluble iron salt to the second mixed solution, stirring, washing, and drying to obtain a first powder; and obtaining a target powder, grinding and calcining the target powder to obtain a carbon material, wherein the target powder comprises the first powder.
2. The method for producing a carbon material according to claim 1, wherein Before the step of obtaining the target powder, the method further comprises the following steps: dissolving phytic acid with lignin and cellulose in water, stirring to obtain a third mixed solution; washing the third mixed solution by suction filtration to obtain a first product; and freezing the first product, and freeze-drying the frozen first product to obtain a polymerization product of phytic acid and melamine, the step of obtaining the target powder comprises the following steps: mixing the polymerization product of phytic acid and melamine with the first powder to obtain the target powder.
3. The method of producing a carbon material according to claim 1 or 2, characterized by, In the step of grinding and calcining the target powder, the device used in the calcination process comprises a tube furnace; and / or, the temperature of the calcination is 700-1000℃; and / or, the time of the calcination is 1-4h.
4. The method of producing a carbon material according to claim 1 or 2, characterized by, In the step of grinding and calcining the target powder, the calcination process is carried out under the protection of a protective gas.
5. The method of producing a carbon material according to claim 4, wherein The protective gas comprises nitrogen.
6. The method of producing a carbon material according to claim 1 or 2, characterized by, The lignin and the cellulose are obtained from biomass.
7. The method of producing a carbon material according to claim 6, wherein The biomass comprises at least one of pear wood, apple wood, jujube wood, peach wood, apricot shell, walnut shell, and cotton stalk.
8. The method of producing a carbon material according to claim 1 or 2, characterized by, The soluble iron salt comprises at least one of ferric chloride, ferric nitrate, and ferric sulfate.
9. A carbon material, characterized by, The carbon material is prepared by the method according to any one of claims 1-8.
10. Use of a carbon material prepared according to the process of any one of claims 1 to 8, characterized in that, It is applied as a catalyst in electrocatalytic oxygen reduction reaction.