CN112316970A - Preparation method and application of multi-defect graphite-phase carbon nitride photocatalyst - Google Patents
Preparation method and application of multi-defect graphite-phase carbon nitride photocatalyst Download PDFInfo
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- JMANVNJQNLATNU-UHFFFAOYSA-N oxalonitrile Chemical compound N#CC#N JMANVNJQNLATNU-UHFFFAOYSA-N 0.000 title claims abstract description 27
- 238000002360 preparation method Methods 0.000 title claims abstract description 11
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 80
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 41
- 230000001699 photocatalysis Effects 0.000 claims abstract description 24
- 239000002243 precursor Substances 0.000 claims abstract description 24
- QGBSISYHAICWAH-UHFFFAOYSA-N dicyandiamide Chemical compound NC(N)=NC#N QGBSISYHAICWAH-UHFFFAOYSA-N 0.000 claims abstract description 20
- KGBXLFKZBHKPEV-UHFFFAOYSA-N boric acid Chemical compound OB(O)O KGBXLFKZBHKPEV-UHFFFAOYSA-N 0.000 claims abstract description 19
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- 238000000034 method Methods 0.000 claims abstract description 16
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 17
- 229910021642 ultra pure water Inorganic materials 0.000 claims description 14
- 239000012498 ultrapure water Substances 0.000 claims description 14
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 claims description 10
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- JIHQDMXYYFUGFV-UHFFFAOYSA-N 1,3,5-triazine Chemical group C1=NC=NC=N1 JIHQDMXYYFUGFV-UHFFFAOYSA-N 0.000 description 2
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- 125000004433 nitrogen atom Chemical group N* 0.000 description 1
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- 229910052724 xenon Inorganic materials 0.000 description 1
- FHNFHKCVQCLJFQ-UHFFFAOYSA-N xenon atom Chemical compound [Xe] FHNFHKCVQCLJFQ-UHFFFAOYSA-N 0.000 description 1
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
- B01J27/24—Nitrogen compounds
- B01J27/26—Cyanides
-
- B01J35/39—
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01C—AMMONIA; CYANOGEN; COMPOUNDS THEREOF
- C01C1/00—Ammonia; Compounds thereof
- C01C1/02—Preparation, purification or separation of ammonia
- C01C1/026—Preparation of ammonia from inorganic compounds
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts
Abstract
The invention relates to a preparation method and application of a multi-defect graphite phase carbon nitride material. The VN-BC-CN photocatalyst is obtained by performing rotary evaporation on a mixed aqueous solution of dicyandiamide and boric acid at 70-90 ℃ and performing thermal condensation on an obtained precursor at 550-650 ℃. The invention has the advantages of low price of raw materials, simple synthesis process, good repeatability and easy large-scale production. The VN-BC-CN photocatalyst prepared by the method disclosed by the invention has three defects of nitrogen vacancy, boron impurity atoms and cyano, the impedance of the material is reduced, and the defect energy level is realized, so that the photocatalytic reaction is facilitated. The nitrogen fixation efficiency of VN-BC-CN can reach 39.28mg/L/g within 2h by applying the nitrogen fixation agent to photocatalysiscatThe photocatalytic nitrogen fixation efficiency of the pure graphite phase carbon nitride prepared by the same method without adding boric acid is 25.5 times.
Description
Technical Field
The invention relates to the technical field of photocatalysts, in particular to a preparation method and application of a multi-defect graphite-phase carbon nitride photocatalyst.
Background
Ammonia is a very important chemical substance in industrial and agricultural development, but the nitrogen fixation mode and the nitrogen fixation amount owned by the nature cannot meet the requirements of industrial and agricultural development, and the artificial synthesis of ammonia is indispensable. At present, the Haber-Bosch method is the most industrially applied method, but the method can be carried out at high temperature and high pressure, a large amount of hydrogen energy is needed, the method is a high-energy-consumption industry, and a large amount of carbon dioxide is released in the production process, so that the method does not meet the new requirements of energy conservation, greenness and environmental protection in the industry at present, and the method requires to find a new way for synthesizing ammonia. The photocatalytic nitrogen fixation can utilize clean and renewable solar energy as an energy source, the reaction can be carried out under the mild condition of normal temperature and normal pressure, the raw materials use nitrogen and water, the byproduct is oxygen, and the method is harmless to the environment, energy-saving and environment-friendly and is the most promising artificial nitrogen fixation mode. However, the development of photocatalytic nitrogen fixation is not mature at present, and a plurality of technical problems are faced, and a proper photocatalyst is one of the technical problems.
The graphite phase carbon nitride is a non-metal semiconductor photocatalyst with excellent performance recognized in the material field at present, the band gap and the energy band position of the graphite phase carbon nitride can meet the requirements of photocatalysis nitrogen fixation, the source of synthetic raw materials is wide, the cost is low, the preparation process is simple, and the graphite phase carbon nitride photocatalyst is expected to realize large-scale production. But the material has low adsorptivity to nitrogen, electrons and holes generated by light excitation are easy to recombine, the utilization rate of visible light is low, and the photocatalysis nitrogen fixation performance of the material is restricted.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention aims to provide a preparation method and application of a multi-defect graphite-phase carbon nitride photocatalyst, the obtained VN-BC-CN photocatalyst has three defects of nitrogen vacancy, boron impurity atoms and cyano, the impedance of the material is reduced, the defect level is realized, the photocatalytic reaction is facilitated, the price of the raw material is low, the synthesis process is simple, the repeatability is good, and the large-scale production is easy.
In order to achieve the purpose, the invention adopts the technical scheme that:
a preparation method of a multi-defect graphite phase carbon nitride photocatalyst comprises the following steps;
step 1: adding dicyandiamide and boric acid into 40-60 mL of ultrapure water in sequence, uniformly stirring, continuously stirring by using a constant-temperature oil bath to evaporate water in the mixed aqueous solution, and drying the obtained solid at 50-70 ℃ to obtain a precursor;
step 2: and putting the obtained precursor into a tube furnace for calcination, and slowly cooling to room temperature after calcination to obtain the VN-BC-CN photocatalyst.
In the step 1, the mass ratio of dicyandiamide to boric acid is 1: 0.09-0.27.
The temperature of the constant-temperature oil bath in the step 1 is 70-90 ℃.
The heating rate in the step 2 is 1-5 ℃/min.
The calcination temperature in the step 2 is 550-650 ℃.
And the calcining time in the step 2 is 3-5 h.
The VN-BC-CN photocatalyst is used for photocatalytic nitrogen fixation.
The VN-BC-CN photocatalyst was used with ultra pure water as a proton source to convert nitrogen to ammonia without the addition of a hole trapping agent.
The invention has the beneficial effects that:
1) by adopting the preparation method, three defects, namely boron atoms, cyano doping and nitrogen vacancies, simultaneously appear in the graphite-phase carbon nitride framework, and the existence of the defects causes the appearance of defect energy levels between a valence band and a conduction band, so that the material has better photocatalytic performance. The defect energy level of the material is close to the position of a conduction band, and the existence of the defect energy level can prevent the recombination of photo-generated electrons and holes on one hand, and can utilize the photo-generated electrons excited by light with lower energy on the other hand, namely, the light with longer wavelength can be utilized, and the ultraviolet-visible diffuse reflection spectrum of the material is shown as the red shift of the light absorption edge of the VN-BC-CN catalyst in figure 3.
2) The VN-BC-CN catalyst has reduced impedance, and photo-generated electrons generated by light excitation can be transferred to effective active sites to participate in a photocatalytic reaction more quickly, so that the photo-generated electrons and holes are effectively separated, and the utilization rate of photo-generated carriers is improved.
3) The nitrogen vacancy in the VN-BC-CN catalyst can accommodate electrons and selectively adsorb nitrogen molecules, and boron and cyano can be used as an electron acceptor after being doped into a graphite-phase carbon nitride framework. The material is suitable for photocatalytic reaction with main reaction at the position of the conduction band of the material, and is preferably applied to photocatalytic nitrogen fixation.
4) The invention adopts ultrapure water as a proton source to carry out the photocatalysis nitrogen fixation reaction. In order to improve the photocatalytic nitrogen fixation efficiency, a hole trapping agent is generally added into a reaction solution to prevent the recombination of photon-generated carriers, so that the utilization rate of photon-generated electrons is improved. The VN-BC-CN material 1) to 3) has excellent characteristics, so that the hole trapping agent is not used in the photocatalytic nitrogen fixation reaction solution.
Drawings
Figure 1 is an XRD pattern of example 1 and comparative example 1.
Fig. 2 is an ir spectrum of example 1 and comparative example 1.
Figure 3 is XPS spectra for example 1 and comparative example 1: (a) a full spectrum; (b) c1 s; (c) n1 s; (d) b1 s.
Fig. 4 is the uv-vis diffuse reflectance spectra of example 1 and comparative example 1.
Fig. 5 is an electrochemical impedance spectrum of example 1 and comparative example 1.
Fig. 6 shows the photocatalytic nitrogen fixation performance of example 1 and comparative example 1.
Detailed Description
The present invention will be described in further detail with reference to examples.
The preparation method of the VN-BC-CN photocatalyst comprises the following steps:
step 1: weighing dicyandiamide and boric acid in a mass ratio of 1: 0.09-0.27, sequentially adding dicyandiamide and boric acid into 40-60 mL of ultrapure water, uniformly stirring, continuously stirring by using a constant-temperature oil bath at 70-90 ℃ to evaporate water in the mixed aqueous solution, and drying the obtained solid by using an oven at 60 ℃ to obtain the precursor.
Step 2: and putting the obtained precursor into a tube furnace for calcination, wherein the heating rate is 1-5 ℃/min, the calcination is carried out at 550-650 ℃ for 3-5 h, and then the obtained product is slowly cooled to room temperature to obtain VN-BC-CN.
The application of the VN-BC-CN photocatalyst in photocatalytic nitrogen fixation provided by the invention comprises the following steps:
1) weighing 50mg VN-BC-CN photocatalyst, adding into a photocatalytic reactor, adding 50mL of ultrapure water, connecting the photocatalytic reactor into a photocatalytic system, continuously stirring, vacuumizing the system after checking the complete air tightness of the system, and simultaneously opening cooling circulating water.
2) Introducing high-purity nitrogen (> 99.9%) through an air inlet valve of a photocatalytic system, and continuously stirring for 30min under a dark condition to ensure that the nitrogen establishes absorption-desorption balance in the aqueous solution.
3) Opening xenon lamp after 30min, illuminating for a fixed time interval, taking the solution in the reactor by using an injector with a microporous filter, and injecting the solution into NH in the ion chromatography test solution4 +And (4) concentration.
Example 1:
step 1: weighing 4g of dicyandiamide and 0.72g of boric acid, sequentially adding the dicyandiamide and the boric acid into 50mL of ultrapure water, uniformly stirring, continuously stirring in a constant-temperature oil bath at 80 ℃ to evaporate water in the mixed water solution, and drying the obtained solid in an oven at 60 ℃ to obtain the precursor.
Step 2: and (3) transferring the precursor obtained in the step (1) into a porcelain boat with a cover, putting the porcelain boat into a tube furnace for calcination, wherein the heating rate is 2.3 ℃/min, the calcination is carried out for 4h at the temperature of 600 ℃, and the calcined precursor is slowly cooled to the room temperature to obtain the VN-BC-CN photocatalyst.
Comparative example 1:
step 1: weighing 4g of dicyandiamide, adding the dicyandiamide into 50mL of ultrapure water, uniformly stirring, continuously stirring in a constant-temperature oil bath at 80 ℃ to evaporate water in the mixed water solution, and drying the obtained solid in an oven at 60 ℃ to obtain a precursor.
Step 2: and (2) transferring the precursor obtained in the step (1) into a porcelain boat with a cover, putting the porcelain boat into a tube furnace for calcination, heating the porcelain boat at the rate of 2.3 ℃/min, calcining the porcelain boat at the temperature of 600 ℃ for 4h, and slowly cooling the porcelain boat to room temperature after calcination to obtain pure graphite phase carbon nitride (GCN).
Example 2:
step 1: weighing 4g of dicyandiamide and 0.36g of boric acid, sequentially adding the dicyandiamide and the boric acid into 50mL of ultrapure water, uniformly stirring, continuously stirring in a constant-temperature oil bath at 80 ℃ to evaporate water in the mixed water solution, and drying the obtained solid in an oven at 60 ℃ to obtain the precursor.
Step 2: and (3) transferring the precursor obtained in the step (1) into a porcelain boat with a cover, putting the porcelain boat into a tube furnace for calcination, wherein the heating rate is 2.3 ℃/min, the calcination is carried out for 4h at the temperature of 600 ℃, and the calcined precursor is slowly cooled to the room temperature to obtain the VN-BC-CN photocatalyst.
Example 3:
step 1: weighing 4g of dicyandiamide and 1.08g of boric acid, sequentially adding the dicyandiamide and the boric acid into 50mL of ultrapure water, uniformly stirring, continuously stirring in a constant-temperature oil bath at 80 ℃ to evaporate water in the mixed water solution, and drying the obtained solid in an oven at 60 ℃ to obtain the precursor.
Step 2: and (3) transferring the precursor obtained in the step (1) into a porcelain boat with a cover, putting the porcelain boat into a tube furnace for calcination, wherein the heating rate is 2.3 ℃/min, the calcination is carried out for 4h at the temperature of 600 ℃, and the calcined precursor is slowly cooled to the room temperature to obtain the VN-BC-CN photocatalyst.
Example 4:
step 1: weighing 4g of dicyandiamide and 0.72g of boric acid, sequentially adding the dicyandiamide and the boric acid into 50mL of ultrapure water, uniformly stirring, continuously stirring in a constant-temperature oil bath at 80 ℃ to evaporate water in the mixed water solution, and drying the obtained solid in an oven at 60 ℃ to obtain the precursor.
Step 2: and (3) transferring the precursor obtained in the step (1) into a porcelain boat with a cover, putting the porcelain boat into a tube furnace for calcination, wherein the heating rate is 2.3 ℃/min, the calcination is carried out for 4h at 550 ℃, and the calcined precursor is slowly cooled to the room temperature to obtain the VN-BC-CN photocatalyst.
Example 5:
step 1: weighing 4g of dicyandiamide and 0.72g of boric acid, sequentially adding the dicyandiamide and the boric acid into 50mL of ultrapure water, uniformly stirring, continuously stirring in a constant-temperature oil bath at 80 ℃ to evaporate water in the mixed water solution, and drying the obtained solid in an oven at 60 ℃ to obtain the precursor.
Step 2: and (3) transferring the precursor obtained in the step (1) into a porcelain boat with a cover, putting the porcelain boat into a tube furnace for calcination, wherein the heating rate is 2.3 ℃/min, the calcination is carried out for 4h at 650 ℃, and the calcined precursor is slowly cooled to room temperature to obtain the VN-BC-CN photocatalyst.
Researches find that the shape and size of nitrogen vacancies in the graphite-phase carbon nitride structure are consistent with the shape and size of nitrogen atoms in nitrogen molecules, so that the material can selectively adsorb nitrogen and the adsorption capacity of the material on the nitrogen is improved. The addition of impurity atoms and the formation of self-defects can serve as new active sites and can change the energy band structure of the material, thereby increasing the photocatalytic performance of the material.
The invention uses low-cost dicyandiamide and boric acid as raw materials to prepare boron atom and cyano-codoped nitrogen-containing vacancy graphite-phase carbon nitride (VN-BC-CN), and the preparation process is simple. The VN-BC-CN catalyst has a defect level, is small in electrochemical impedance, improves the separation efficiency of photon-generated carriers and the utilization rate of visible light, and can perform a photocatalytic nitrogen fixation reaction more efficiently by using ultrapure water as a proton source on the premise of not using a hole trapping agent.
Figure 1 shows the XRD patterns of example 1 and comparative example 1, with GCN showing two typical diffraction peaks for graphite phase carbon nitride, located at 13.0 ° and 27.5 °, respectively. The VN-BC-CN photocatalyst has a diffraction peak at 13.0 degrees disappeared, which shows that the 3, s-triazine ring structure of the graphite phase carbon nitride is destroyed and the defect exists. 27.5 corresponds to the typical middle of the material, where VN-BC-CN has a broader peak shape and a weaker peak, indicating that the defect causes a reduction in the structural order of the material.
FIG. 2 shows the IR spectra of example 1 and comparative example 1. With respect to comparative example 1, the vibration absorption peaks corresponding to the 3, s-triazine ring structure, C-N ring, and N-H bond of VN-BC-CN are reduced, and the possible existence positions of defects in the material structure can be illustrated by combining the graphs of FIG. 3(b) C1s and (C) N1 s. In addition, the appearance of C ≡ N and B-N bond vibration absorption peaks indicates that cyano groups and boron atoms in the VN-BC-CN material are successfully doped into a graphite-phase carbon nitride framework, and a small amount of cyano groups exist in the GCN structural framework.
FIG. 3 shows XPS spectra of example 1 and comparative example 1, and the full spectrum (a) and B1s (d) again confirm the boron atomSuccessful doping. In FIG. 3(c), 398.2 and 399.1eV correspond to N in the graphite-phase carbon nitride structure, respectively2CAnd N3C. Wherein, N of GCN2C/N3CN in a ratio of 1.63, VN-BC-CN2C/N3CThe ratio is 2.61, which indicates N in VN-BC-CN3CThe position is deficient in nitrogen, and a nitrogen vacancy is formed.
The uv-vis diffuse reflectance spectra of example 1 and comparative example 1 shown in fig. 4 show that both intrinsic absorption edges of VN-BC-CN and GCN are 467nm, but VN-BC-CN can use less energy of visible light due to the presence of multiple defects in VN-BC-CN, and therefore the corresponding light absorption edges of the defect levels are red-shifted.
FIG. 5 shows the electrochemical impedance spectroscopy of example 1 and comparative example 1, and the arc radius corresponding to the high frequency region of VN-BC-CN is smaller than that of GCN, which shows that VN-BC-CN has smaller charge transfer resistance and easier separation of photogenerated carriers.
Fig. 6 shows the photocatalytic nitrogen fixation performance test of example 1 and comparative example 1. During the 30min dark reaction, no nitrogen fixation reaction occurred between GCN and VN-BC-CN. After 2 hours of illumination, the photocatalytic nitrogen fixation efficiency of GCN is 1.54mg/L/gcatThe photocatalytic nitrogen fixation efficiency of VN-BC-CN can reach 39.28mg/L/gcatAnd/h is 25.5 times of GCN. VN-BC-CN is proved to have better photocatalytic activity.
Claims (8)
1. A preparation method of a multi-defect graphite phase carbon nitride photocatalyst is characterized by comprising the following steps;
step 1: adding dicyandiamide and boric acid into 40-60 mL of ultrapure water in sequence, uniformly stirring, continuously stirring by using a constant-temperature oil bath to evaporate water in the mixed aqueous solution, and drying the obtained solid at 50-70 ℃ to obtain a precursor;
step 2: and putting the obtained precursor into a tube furnace for calcination, and slowly cooling to room temperature after calcination to obtain the VN-BC-CN photocatalyst.
2. The method for preparing a multi-defect graphite-phase carbon nitride photocatalyst according to claim 1, wherein the mass ratio of dicyandiamide to boric acid in the step 1 is 1: 0.09-0.27.
3. The method for preparing the multi-defect graphite-phase carbon nitride photocatalyst according to claim 1, wherein the temperature of the constant-temperature oil bath in the step 1 is 70-90 ℃.
4. The method for preparing a multi-defect graphite-phase carbon nitride photocatalyst according to claim 1, wherein the temperature rise rate in the step 2 is 1-5 ℃/min.
5. The method for preparing a multi-defect graphite-phase carbon nitride photocatalyst according to claim 1, wherein the calcination temperature in the step 2 is 550-650 ℃.
6. The method for preparing a multi-defect graphite-phase carbon nitride photocatalyst according to claim 1, wherein the calcination time in the step 2 is 3-5 h.
7. Use of a multi-defect graphitic-phase carbon nitride photocatalyst according to claims 1-6, wherein the VN-BC-CN photocatalyst is used for photocatalytic nitrogen fixation.
8. The use of a multi-defect graphitic-phase carbon nitride photocatalyst according to claims 1-6, wherein the VN-BC-CN photocatalyst is used as a proton source for converting nitrogen to ammonia without the addition of a hole trapping agent for ultra-pure water.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113441165A (en) * | 2021-07-30 | 2021-09-28 | 陕西科技大学 | VN/g-C3N4Composite photocatalyst and preparation method thereof |
| CN114453001A (en) * | 2022-03-10 | 2022-05-10 | 江苏理工学院 | Aromatic ring and cyano co-doped carbon nitride nanosheet and preparation method and application thereof |
| CN114733543A (en) * | 2022-02-28 | 2022-07-12 | 山东大学 | Boron-modified carbon nitride material and preparation method and application thereof |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106669764A (en) * | 2017-01-20 | 2017-05-17 | 济南大学 | Method for preparing carbon nitride doped nanomaterial with soft-template process |
| CN109569691A (en) * | 2018-12-23 | 2019-04-05 | 上海纳米技术及应用国家工程研究中心有限公司 | Preparation method of boron doping carbonitride and products thereof and application |
| CN110016178A (en) * | 2019-04-28 | 2019-07-16 | 西北师范大学 | A kind of ternary hybrid inorganic-organic materials composite flame-retardant agent and its application |
| CN110183773A (en) * | 2019-07-03 | 2019-08-30 | 西北师范大学 | The preparation method of chitosan quaternary ammonium salt organic intercalation montmorillonite composite material |
| CN111740076A (en) * | 2020-06-22 | 2020-10-02 | 珠海冠宇电池股份有限公司 | Preparation method of nitrogen-doped, boron-doped or phosphorus-doped graphitized carbon nitride material |
-
2020
- 2020-11-03 CN CN202011212460.2A patent/CN112316970A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106669764A (en) * | 2017-01-20 | 2017-05-17 | 济南大学 | Method for preparing carbon nitride doped nanomaterial with soft-template process |
| CN109569691A (en) * | 2018-12-23 | 2019-04-05 | 上海纳米技术及应用国家工程研究中心有限公司 | Preparation method of boron doping carbonitride and products thereof and application |
| CN110016178A (en) * | 2019-04-28 | 2019-07-16 | 西北师范大学 | A kind of ternary hybrid inorganic-organic materials composite flame-retardant agent and its application |
| CN110183773A (en) * | 2019-07-03 | 2019-08-30 | 西北师范大学 | The preparation method of chitosan quaternary ammonium salt organic intercalation montmorillonite composite material |
| CN111740076A (en) * | 2020-06-22 | 2020-10-02 | 珠海冠宇电池股份有限公司 | Preparation method of nitrogen-doped, boron-doped or phosphorus-doped graphitized carbon nitride material |
Non-Patent Citations (1)
| Title |
|---|
| WEIKANG WANG 等: "Formation of B-N-C Coordination to Stabilize the Exposed Active Nitrogen Atoms in g-C3N4 for Dramatically Enhanced Photocatalytic Ammonia Synthesis Performance", 《SMALL》 * |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113441165A (en) * | 2021-07-30 | 2021-09-28 | 陕西科技大学 | VN/g-C3N4Composite photocatalyst and preparation method thereof |
| CN113441165B (en) * | 2021-07-30 | 2022-11-29 | 陕西科技大学 | VN/g-C 3 N 4 Composite photocatalyst and preparation method thereof |
| CN114733543A (en) * | 2022-02-28 | 2022-07-12 | 山东大学 | Boron-modified carbon nitride material and preparation method and application thereof |
| CN114453001A (en) * | 2022-03-10 | 2022-05-10 | 江苏理工学院 | Aromatic ring and cyano co-doped carbon nitride nanosheet and preparation method and application thereof |
| CN114453001B (en) * | 2022-03-10 | 2023-06-06 | 江苏理工学院 | Aromatic ring and cyano co-doped carbon nitride nanosheet as well as preparation method and application thereof |
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