CN114452990A - Method for preparing transition metal carbide and composite catalyst - Google Patents

Method for preparing transition metal carbide and composite catalyst Download PDF

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CN114452990A
CN114452990A CN202011237927.9A CN202011237927A CN114452990A CN 114452990 A CN114452990 A CN 114452990A CN 202011237927 A CN202011237927 A CN 202011237927A CN 114452990 A CN114452990 A CN 114452990A
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carbide
cobalt
molybdenum
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马松
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TCL Technology Group Co Ltd
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Abstract

The application relates to the technical field of photocatalytic materials, and provides a preparation method of a transition metal carbide, which comprises the following steps: providing a transition metal salt and a carbon source; dissolving the transition metal salt and the carbon source in water, and then carrying out heating evaporation treatment to obtain a precursor; and calcining the precursor to obtain the transition metal carbide. The preparation method has the advantages of simple, stable and easily controlled process conditions, high product yield, easy cleaning of impurities and good industrial application prospect.

Description

Method for preparing transition metal carbide and composite catalyst
Technical Field
The application belongs to the technical field of photocatalytic materials, and particularly relates to a preparation method of a transition metal carbide and a composite catalyst.
Background
Hydrogen energy is an ideal alternative to fossil fuels as the most attractive clean and carbon-free energy source, but current industrial technologies are not suitable for producing hydrogen for fuel use. The conversion of solar energy into hydrogen by utilizing a photocatalytic technology is considered to be one of the most promising hydrogen production approaches, and is expected to fundamentally solve the problems of energy shortage and environmental pollution.
The photocatalytic reaction is to convert solar energy into chemical energy with high energy density by utilizing the structural characteristics of a semiconductorAnd stored in the reaction process in the chemical bond. The semiconductor material has a discontinuous energy Band structure including a high-energy empty Conduction Band (CB) and a low-energy full Valence Band (VB). The energy band gaps at the bottom of the conduction band and the top of the valence band, denoted Eg, are called forbidden bands, electrons in the valence band are unstable, and when a semiconductor is irradiated with light having an energy greater than its forbidden band width, the electrons in the valence band absorb the energy and transit to the conduction band, leaving photo-generated holes (h) in the valence band+). The photoproduction electrons on the conduction band have strong reducibility and can convert H+Reduction of ions to H2The photogenerated holes in the valence band have strong oxidizing properties and can oxidize water to O2. The key point of photocatalytic water decomposition hydrogen production is to select a proper photocatalyst. Early photocatalysts such as TiO2Most of the solar energy is ultraviolet light response (ultraviolet light accounts for 5% of the solar energy, and visible light accounts for about 46% of the solar energy), the utilization rate of the solar light is too low, the valence band and conduction band potentials cannot simultaneously meet the requirement of catalytic reaction, the photo-generated electron-hole pairs are easy to recombine, the quantum efficiency is low, the cost is too high, and the like. Therefore, it is difficult to find a cheap and commercially available material satisfying all the conditions of high visible light quantum efficiency, stability, safety, and cheapness.
The surface electron hole pair is easy to recombine, the electron consumption rate is too low, and two important factors influencing the photocatalysis efficiency are provided. Most of the traditional cocatalyst is precious metal such as Pt, Ag and Au, the precious metal has lower Fermi level and higher work function, and can promote electrons to transfer from a semiconductor to the semiconductor after forming a Schottky junction with the semiconductor and quickly react with protons, so that the photocatalytic activity of the semiconductor is improved, but the traditional cocatalyst has rare reserves and high price, and limits industrial application. Scientists now turn their research efforts to find a highly efficient, inexpensive non-noble metal promoter, the new non-noble metal promoter of interest being MoS2、WS2Metal sulfides such as NiS, and carbon materials such as graphene, carbon black, carbon nanotubes, and C60Most have a typical two-dimensional structure, a large specific surface area and excellent conductivity, but still have some disadvantages. Transition metal carbide is regarded as a promising photocatalytic hydrogen production promoter, but the prior laboratory synthesis method of transition metal carbide usually adopts transition metal salt to react with an organic phase at high temperature in an oxygen-free atmosphere, the reaction condition requirement is higher, the reaction progress is difficult to control, and after the reaction is finished, the viscosity of organic phase impurities is high, and the organic phase impurities are not easy to clean, so that the product impurities are more, the yield is low, and further application is influenced.
Therefore, the related art is in need of improvement.
Disclosure of Invention
The application aims to provide a preparation method of a transition metal carbide and a composite catalyst, and aims to solve the technical problem that the existing preparation condition of the transition metal carbide is complex.
In order to achieve the purpose of the application, the technical scheme adopted by the application is as follows:
in a first aspect, the present application provides a method for preparing a transition metal carbide, comprising the steps of:
providing a transition metal salt and a carbon source;
dissolving the transition metal salt and the carbon source in water, and then carrying out heating evaporation treatment to obtain a precursor;
and calcining the precursor to obtain the transition metal carbide.
The preparation method of the transition metal carbide provided by the application takes transition metal salt and a carbon source as raw materials, the transition metal salt and the carbon source are dissolved in water, the transition metal salt is hydrolyzed to form transition metal hydroxide colloid and corresponding acid in heating evaporation, the acid is volatilized in the heating process, the transition metal hydroxide colloid has extremely strong adsorbability, the carbon source can be uniformly adsorbed to form precursor solid solution, the transition metal hydroxide is decomposed to form metal oxide in the precursor calcining process, and the metal oxide is further carbonized by molecular carbon formed by saccharide decomposition to form the transition metal carbide.
In a second aspect, the present application provides a composite catalyst comprising a main catalyst and a promoter, the promoter comprising a transition metal carbide obtained by the above-described preparation method of the present application.
The cocatalyst in the composite catalyst comprises the transition metal carbide obtained by the special preparation method, and the transition metal carbide has high purity and better hydrogen production rate, so that the composite catalyst has better photocatalysis effect.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
FIG. 1 is a schematic flow chart of a method for preparing a transition metal carbide according to an embodiment of the present disclosure;
FIG. 2 is a graph comparing the photo-hydrogen production activity of a composite catalyst prepared by using transition metal carbide as a promoter provided in the examples of the present application;
figure 3 is a XRD contrast of nickel carbide provided in the examples of the present application.
Detailed Description
In order to make the technical problems, technical solutions and advantageous effects to be solved by the present application more clearly apparent, the present application is further described in detail below with reference to the embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.
In this application, the term "and/or" describes an association relationship of associated objects, meaning that there may be three relationships, e.g., a and/or B, which may mean: a is present alone, A and B are present simultaneously, and B is present alone. Wherein A and B can be singular or plural. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship.
The terminology used in the embodiments of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in the examples of this application and the appended claims, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.
The weight of the related components mentioned in the description of the embodiments of the present application may not only refer to the specific content of each component, but also represent the proportional relationship of the weight among the components, and therefore, the content of the related components is scaled up or down within the scope disclosed in the description of the embodiments of the present application as long as it is scaled up or down according to the description of the embodiments of the present application. Specifically, the mass described in the specification of the embodiments of the present application may be a mass unit known in the chemical industry field such as μ g, mg, g, kg, etc.
In a first aspect of the embodiments of the present application, there is provided a method for preparing a transition metal carbide, as shown in fig. 1, the method comprising the steps of:
s01: providing a transition metal salt and a carbon source;
s02: dissolving the transition metal salt and the carbon source in water, and then carrying out heating evaporation treatment to obtain a precursor;
s03: and calcining the precursor to obtain the transition metal carbide.
The preparation method of the transition metal carbide provided by the application takes transition metal salt and a carbon source as raw materials, the transition metal salt and the carbon source are dissolved in water, the transition metal salt is hydrolyzed to form transition metal hydroxide colloid and corresponding acid in heating evaporation, the acid is volatilized in the heating process, the transition metal hydroxide colloid has extremely strong adsorbability, the carbon source can be uniformly adsorbed to form precursor solid solution, the transition metal hydroxide is decomposed to form metal oxide in the precursor calcining process, and the metal oxide is further carbonized by molecular carbon formed by saccharide decomposition to form the transition metal carbide.
In some embodiments, the transition metal is selected from the group consisting ofThe salt is soluble salt, specifically can be transition metal nitrate, transition metal chloride, transition metal acetate and the like, and the transition metal salt can be hydrolyzed in the heating and evaporation process after being dissolved in water to form transition metal hydroxide colloid and corresponding acid, preferably transition metal acetate, so that the formed acetic acid can be better volatilized; specifically, when the transition metal salt is selected from nickel metal salts selected from at least one of nickel nitrate, nickel acetate and nickel chloride, the resulting transition metal carbide is nickel carbide (Ni)3C) (ii) a When the transition metal salt is selected from tungsten metal salts selected from at least one of tungsten nitrate and tungsten chloride, the resulting transition metal carbide is tungsten carbide (WC); when the transition metal salt is selected from manganese metal salts selected from at least one of manganese nitrate, manganese acetate and manganese chloride, the transition metal carbide obtained is manganese carbide (Mn)3C) (ii) a When the transition metal salt is selected from cobalt metal salts selected from at least one of cobalt nitrate, cobalt acetate and cobalt chloride, the obtained transition metal carbide is cobalt carbide (Co)3C) (ii) a When the transition metal salt is selected from molybdenum metal salts selected from at least one of molybdenum nitrate, molybdenum acetate and molybdenum chloride, the transition metal carbide obtained is molybdenum carbide (MoC)2) (ii) a When the transition metal salt is selected from iron metal salts selected from at least one of iron nitrate, iron acetate and iron chloride, the resulting transition metal carbide is iron carbide (Fe)3C) In that respect The transition metal salt according to the embodiment of the present application is selected from any one of nickel metal salt, tungsten metal salt, manganese metal salt, cobalt metal salt, molybdenum metal salt and iron metal salt, so that different transition metal carbides may be calcined in a tube furnace, and further, the transition metal carbide may preferably be Fe3C、Co3C and Ni3C。
In some embodiments, the carbon source may be a carbon source without N, S and halogen, such as C, H, O carbohydrate, and particularly, the carbon source may preferably be a saccharide material, which is not only cheap and easily available, but also soluble in water to prepare a precursor, has a high carbon content, and does not contain N, S and halogen which are not easily volatilized during high-temperature calcination. Further, the saccharide may include one or more of glucose, fructose, sucrose, chitosan and other common saccharides.
In some embodiments, in the step of dissolving the transition metal salt and the carbon source in water, the weight ratio of the transition metal salt to the carbon source is 1: 1-10. The excessive carbon source can be fully carbonized to obtain the transition metal carbide.
In some embodiments, the temperature of the heating evaporation treatment is 80-100 ℃. Heating at this temperature allows the transition metal salt to be hydrolyzed sufficiently.
In some embodiments, the temperature of the calcination treatment is 500 to 600 ℃. Further, calcining for 4-8h at 500-600 ℃. Under the calcination condition, molecular carbon formed by the decomposition of the saccharides can be fully carbonized to form transition metal carbides. Furthermore, in the calcination treatment, the temperature is raised to 500-600 ℃ at a temperature rise rate of 4-6 ℃/min, and the temperature rise rate enables the reaction system to be more stable. In the temperature rise process, the transition metal hydroxide is decomposed to form a metal oxide, and the metal oxide is carbonized by molecular carbon formed by decomposition of the saccharides under the calcination condition of 500-600 ℃ to form a transition metal carbide.
Accordingly, embodiments of the present application provide a transition metal carbide prepared by the above-described method for preparing a transition metal carbide of the present application.
The transition metal carbide provided by the application is prepared by the preparation method of the above-mentioned peculiar transition metal carbide of this application, and such transition metal carbide purity is high, can regard as cocatalyst and main catalyst complex, and the hydrogen production rate of the transition metal carbide cocatalyst of comparing the preparation of current method promotes the effect better, consequently has better application in the photocatalysis field.
In a second aspect, embodiments of the present application provide a composite catalyst, which includes a main catalyst and a promoter, where the promoter includes a transition metal carbide obtained by the above-described preparation method of the present application.
The cocatalyst in the composite catalyst comprises the transition metal carbide obtained by the special preparation method, and the transition metal carbide has high purity and better hydrogen production rate, so that the composite catalyst has better photocatalysis effect.
In some embodiments, the above-mentioned promoter may be Ni prepared in the examples of this application3C、WC、Mn3C、Co3C、MoC2And Fe3C and the like.
In some embodiments, the primary catalyst can be CdS nanosheet or g-C3N4(graphite phase carbon nitride), and the main catalyst is compounded with the transition metal carbide obtained by the preparation method to prepare a composite catalyst and verify the better photocatalytic hydrogen production performance of the composite catalyst.
Wherein the CdS nanosheet and ultrathin g-C3N4Can be obtained from the market or obtained by the following preparation method.
Ultra-thin g-C3N4Preparation: and (3) uniformly stirring 15g of urea and 10g of ammonium chloride in a container, then putting the container into a crucible, and calcining the mixture for 2 hours at 550 ℃ in a muffle furnace at the heating rate of 4 ℃/min. Washing the calcined product with distilled water, centrifuging at 8000rpm, drying in vacuum oven at 60 deg.C for 12 hr, and grinding to obtain ultrathin g-C3N4And (3) powder.
Preparing CdS nanosheets: 0.6g sublimed sulphur powder and 0.7g CdCl22.5H2O was dissolved in 75mL of Diethylenetriamine (DETA) and mixed well by ultrasonic stirring for 30 min. The mixture was then transferred to a 100mL teflon lined reactor. The reaction kettle is heated to 80 ℃ in an oven and kept for 48 hours, and after the reaction kettle is naturally cooled to room temperature, a light yellow product is obtained through centrifugation at 3000 rpm. And then washing the product with deionized water and absolute ethyl alcohol for three times respectively, and drying the product in a vacuum drying oven at 60 ℃ for 8 hours to obtain the CdS nanosheet.
The following description will be given with reference to specific examples.
Example 1
Preparation of composite catalyst
(1) Co promoter3C, preparation:
2g of cobalt acetate and 10g of glucose powder are takenDissolving in 30mL deionized water, stirring for 30 minutes, uniformly mixing, heating at 80 ℃ to evaporate deionized water, continuously stirring with a glass rod until a viscous colloid is obtained, then placing the colloid in a porcelain boat, calcining at 550 ℃ for 5 hours in a tubular furnace, heating at the rate of 5 ℃/min, washing the calcined product with distilled water for three times, centrifugally collecting at 5000rpm, drying in a vacuum oven at 60 ℃ for 8 hours, and grinding to obtain Co3And C, powder.
(2) Preparing a composite catalyst:
100mg CdS powder and 5mg Co obtained above3Putting the powder C into 50mL deionized water, performing ultrasonic treatment for 2h to disperse the powder C uniformly, then continuously stirring for 18h, centrifuging at 5000rpm to obtain a yellow-green precipitate, cleaning with absolute ethyl alcohol, putting into an oven for drying at 60 ℃ for 10h, and grinding to obtain Co3C/CdS composite catalyst.
Example 2
Preparation of composite catalyst
(1) Cocatalyst Fe3C, preparation:
dissolving 2.5g of ferric chloride and 8g of chitosan powder in 30mL of deionized water, stirring for 30 minutes, uniformly mixing, heating to evaporate the deionized water at 80 ℃ and continuously stirring by using a glass rod until a viscous colloid is obtained, then placing the colloid in a porcelain boat, placing in a tubular furnace for calcining at 600 ℃ for 4 hours at the heating rate of 5 ℃/min, washing a calcined product with distilled water for three times, centrifugally collecting at 6000rpm, placing in a vacuum oven for drying at 60 ℃ for 8 hours, and then grinding to obtain Fe3And C, powder.
(2) Preparing a composite catalyst:
200mg of g-C3N4Powder and 14mg of Fe obtained above3Putting the powder C into 100mL deionized water, performing ultrasonic treatment for 2h to disperse the powder C uniformly, then continuously stirring for 18h, centrifuging at 6000rpm to obtain gray precipitate, cleaning with absolute ethyl alcohol, putting into a vacuum oven for drying at 60 ℃ for 8h, and grinding to obtain Fe3C/g-C3N4And (3) compounding a catalyst.
Example 3
Preparation of composite catalyst
(1) Cocatalyst Ni3C, preparation:
dissolving 3g of nickel acetate and 9g of glucose powder in 30mL of deionized water, stirring for 30 minutes, uniformly mixing, heating to evaporate deionized water at 80 ℃ and continuously stirring by using a glass rod until a viscous colloid is obtained, then placing the colloid in a porcelain boat, calcining for 6 hours at 500 ℃ in a tubular furnace at the heating rate of 5 ℃/min, washing a calcined product for three times by using distilled water, centrifugally collecting at 5000rpm, drying for 8 hours at 60 ℃ in a vacuum oven, and then grinding to obtain Ni3And C, powder.
(2) Preparing a composite catalyst:
200mg of g-C3N4Powder and 10mg of Ni obtained above3Putting the powder C into 100mL deionized water, performing ultrasonic treatment for 2h to disperse the powder C uniformly, then continuously stirring for 18h, centrifuging at 5000rpm to obtain gray precipitate, cleaning with absolute ethyl alcohol, putting into a vacuum oven at 60 ℃ for drying for 8h, and grinding to obtain Ni3C/g-C3N4And (3) compounding a catalyst.
Comparative example 1
Preparation of composite catalyst
(1) Co promoter3C, preparation:
cobalt acetate and oleylamine were used as raw materials, and the mixture was put into a three-necked round-bottomed flask and was magnetically stirred continuously in a nitrogen atmosphere. Then heated to 280 ℃ with an oil bath and incubated for 2 h. After the reaction is finished and the mixture is naturally cooled to room temperature, 30mL of acetone is added into the mixture, then black precipitate is collected by centrifugation, and the mixture is washed for a plurality of times by deionized water and absolute ethyl alcohol respectively to remove organic impurities, so that Co is obtained3And C, powder.
(2) Preparing a composite catalyst:
100mg CdS powder and 5mg Co obtained above3Putting the powder C into 50mL deionized water, performing ultrasonic treatment for 2h to disperse the powder C uniformly, then continuously stirring for 18h, centrifuging at 5000rpm to obtain a yellow-green precipitate, cleaning with absolute ethyl alcohol, putting into an oven for drying at 60 ℃ for 10h, and grinding to obtain Co3C/CdS composite catalyst.
Comparative example 2
Preparation of composite catalyst
(1) Cocatalyst Fe3Preparation of C：
Ferric chloride and oleylamine were used as raw materials, added to a three-necked round-bottomed flask, and magnetically stirred continuously in a nitrogen atmosphere. Then heated to 280 ℃ with an oil bath and incubated for 2 h. After the reaction is finished and the mixture is naturally cooled to room temperature, 30mL of acetone is added into the mixture, then black precipitate is collected by centrifugation, and the mixture is washed for a plurality of times by deionized water and absolute ethyl alcohol respectively to remove organic impurities, so that Fe is obtained3And C, powder.
(2) Preparing a composite catalyst:
200mg of g-C3N4Powder and 14mg of Fe obtained above3Putting the powder C into 100mL deionized water, performing ultrasonic treatment for 2h to disperse the powder C uniformly, then continuously stirring for 18h, centrifuging at 6000rpm to obtain gray precipitate, cleaning with absolute ethyl alcohol, putting into a vacuum oven for drying at 60 ℃ for 8h, and grinding to obtain Fe3C/g-C3N4And (3) compounding a catalyst.
Comparative example 3
Preparation of composite catalyst
(1) Cocatalyst Ni3C, preparation:
nickel acetate and oleylamine were used as raw materials, added to a three-neck round-bottomed flask, and magnetically stirred continuously in a nitrogen atmosphere. Then heated to 280 ℃ with an oil bath and incubated for 2 h. After the reaction is finished and the mixture is naturally cooled to room temperature, 30mL of acetone is added into the mixture, then black precipitate is collected by centrifugation, and the mixture is washed for a plurality of times by deionized water and absolute ethyl alcohol respectively to remove organic impurities, so that Ni is obtained3And C, powder.
(2) Preparing a composite catalyst:
200mg of g-C3N4Powder and 10mg Ni obtained as described above3Putting the powder C into 100mL deionized water, performing ultrasonic treatment for 2h to disperse the powder C uniformly, then continuously stirring for 18h, centrifuging at 5000rpm to obtain gray precipitate, cleaning with absolute ethyl alcohol, putting into a vacuum oven at 60 ℃ for drying for 8h, and grinding to obtain Ni3C/g-C3N4And (3) compounding a catalyst.
Performance testing
(1) Visible light hydrogen production activity: the hydrogen production device is tested by using a Beijing Bofelea water photolysis hydrogen production device, and hydrogen produced in the reaction process is detected on line by using a (GC-9500) type gas chromatograph. The method comprises the following specific steps: 250mg of the composite catalysts prepared in examples 1-3 and comparative examples 1-3 were charged into a reactor, respectively, and 100mL of a 10 vol% aqueous solution of lactic acid or triethanolamine was added as a sacrificial agent. After 30min of ultrasonic dispersion, the reactor was sealed, the whole reaction system was evacuated to-0.1 MPa with a vacuum pump, continuous visible light irradiation with a xenon lamp (PLS-CHF, 300W,. lambda. >420nm) was carried out with uninterrupted magnetic stirring, and the reaction was carried out for a total of 3 hours with sampling every half hour, the results being shown in FIG. 2.
As can be seen from FIG. 2, CdS nanosheets and g-C3N4Hydrogen production Rate (Rate of H) simply as photocatalyst2evolution) is low, but it is loaded with Fe prepared in the examples of the present application3C、Co3C and Ni3After C, compared with a single photocatalyst, the hydrogen production rate of the formed composite catalyst is greatly improved, and the hydrogen production rate of the composite catalyst is higher than that of the composite catalyst formed by the transition metal carbide cocatalyst prepared by a conventional method in proportion. Therefore, the application proves that the transition metal carbide obtained by the preparation method has great application potential in the field of photocatalytic hydrogen production as a cocatalyst, and can be widely applied to more photocatalysts.
(2) Crystal structure characterization (XRD): ni prepared in example 3 and comparative example 33The crystal structure of the sample C was analyzed by an X-ray powder diffractometer (MSAL-XD2) at a scanning rate of 4 or 8 DEG/min and a phase of the sample was analyzed at 2 theta in the range of 15 to 80 DEG, and the results are shown in FIG. 3.
FIG. 3 shows Ni prepared by the conventional method of comparative example 33C and Ni prepared in example 3 of the present application3C standard diffraction pattern, Ni obtained by the preparation method of the application according to literature and XRD spectrogram3C crystal phase and standard hexagonal crystal phase Ni3C (JCPDS No: 72-1467) matched well and Ni was observed3The C sample has 6 characteristic diffraction peaks respectively corresponding to the hexagonal phase Ni3C (100),(006) And (113), (116), (300), and (119), while no diffraction peak of residue or impurity is observed. And Ni synthesized in comparative example 3 by the conventional method of comparative example 33C crystal phase Ni of hexagonal phase substantially matching the standard3C (JCPDS No: 72-1467), but the diffraction peak shape was not good and there was an impurity diffraction peak. It is shown that the high-purity Ni can be prepared in the example 3 of the present application3And C, material.
The above description is only a preferred embodiment of the present application and should not be taken as limiting the present application, and any modifications, equivalents, improvements, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims (10)

1. A preparation method of transition metal carbide is characterized by comprising the following steps:
providing a transition metal salt and a carbon source;
dissolving the transition metal salt and the carbon source in water, and then carrying out heating evaporation treatment to obtain a precursor;
and calcining the precursor to obtain the transition metal carbide.
2. The method according to claim 1, wherein in the step of dissolving the transition metal salt and the carbon source in water, the weight ratio of the transition metal salt to the carbon source is 1:1 to 10.
3. The method according to claim 1, wherein the temperature of the thermal evaporation treatment is 80 to 100 ℃.
4. The method according to claim 1, wherein the temperature of the calcination treatment is 500 to 600 ℃.
5. The method according to claim 4, wherein the temperature is raised to 500 to 600 ℃ at a temperature raising rate of 4 to 6 ℃/min during the calcination treatment; and/or the presence of a gas in the gas,
in the calcining treatment, calcining is carried out for 4-8h at the temperature of 500-600 ℃.
6. The production method according to any one of claims 1 to 5, wherein the transition metal salt is selected from any one of a nickel metal salt, a tungsten metal salt, a manganese metal salt, a cobalt metal salt, a molybdenum metal salt, and an iron metal salt; and/or the presence of a gas in the gas,
the carbon source is selected from carbohydrates.
7. The production method according to claim 6, wherein when the transition metal salt is selected from a nickel metal salt selected from at least one of nickel nitrate, nickel acetate and nickel chloride, the obtained transition metal carbide is nickel carbide;
when the transition metal salt is selected from tungsten metal salts, the tungsten metal salt is selected from at least one of tungsten nitrate and tungsten chloride, and the obtained transition metal carbide is tungsten carbide;
when the transition metal salt is selected from manganese metal salts, the manganese metal salt is selected from at least one of manganese nitrate, manganese acetate and manganese chloride, and the obtained transition metal carbide is manganese carbide;
when the transition metal salt is selected from cobalt metal salts, the cobalt metal salt is selected from at least one of cobalt nitrate, cobalt acetate and cobalt chloride, and the obtained transition metal carbide is cobalt carbide;
when the transition metal salt is selected from molybdenum metal salt, the molybdenum metal salt is selected from at least one of molybdenum nitrate, molybdenum acetate and molybdenum chloride, and the obtained transition metal carbide is molybdenum carbide;
when the transition metal salt is selected from iron metal salts, the iron metal salt is selected from at least one of ferric nitrate, ferric acetate and ferric chloride, and the obtained transition metal carbide is ferric carbide.
8. The method according to claim 6, wherein the saccharide is at least one selected from the group consisting of glucose, fructose, sucrose and chitosan.
9. A composite catalyst comprising a main catalyst and a co-catalyst, wherein the co-catalyst comprises a transition metal carbide produced by the production method according to any one of claims 1 to 8.
10. The composite catalyst according to claim 9, wherein the main catalyst is CdS nanosheet or g-C3N4。
CN202011237927.9A 2020-11-09 2020-11-09 Method for preparing transition metal carbide and composite catalyst Pending CN114452990A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115845885A (en) * 2022-10-20 2023-03-28 江苏大学 CdS/WC 1-x @ C composite photocatalyst and preparation method and application thereof

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115845885A (en) * 2022-10-20 2023-03-28 江苏大学 CdS/WC 1-x @ C composite photocatalyst and preparation method and application thereof
CN115845885B (en) * 2022-10-20 2024-05-10 江苏大学 CdS/WC1-xComposite photocatalyst @ C and preparation method and application thereof

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