CN115739193B - Synthesis and application of carbon nitride/MOFs composite material - Google Patents
Synthesis and application of carbon nitride/MOFs composite material Download PDFInfo
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- JDSHMPZPIAZGSV-UHFFFAOYSA-N melamine Chemical compound NC1=NC(N)=NC(N)=N1 JDSHMPZPIAZGSV-UHFFFAOYSA-N 0.000 claims abstract description 11
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- 229940078487 nickel acetate tetrahydrate Drugs 0.000 claims description 3
- OINIXPNQKAZCRL-UHFFFAOYSA-L nickel(2+);diacetate;tetrahydrate Chemical group O.O.O.O.[Ni+2].CC([O-])=O.CC([O-])=O OINIXPNQKAZCRL-UHFFFAOYSA-L 0.000 claims description 3
- 230000035484 reaction time Effects 0.000 claims description 3
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- 230000001699 photocatalysis Effects 0.000 abstract description 34
- 239000003795 chemical substances by application Substances 0.000 abstract description 21
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 abstract description 10
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- YJTKZCDBKVTVBY-UHFFFAOYSA-N 1,3-Diphenylbenzene Chemical group C1=CC=CC=C1C1=CC=CC(C=2C=CC=CC=2)=C1 YJTKZCDBKVTVBY-UHFFFAOYSA-N 0.000 abstract 1
- 239000012924 metal-organic framework composite Substances 0.000 description 34
- 239000000463 material Substances 0.000 description 23
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 15
- -1 uranyl ions Chemical class 0.000 description 13
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- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
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Abstract
The invention discloses synthesis and application of a carbon nitride/MOFs composite material, and belongs to the technical field of photocatalysis. The synthesis method comprises the following steps: mixing urea, melamine, sodium hydroxide and potassium chloride, calcining in an inert atmosphere, centrifuging, washing and drying to obtain carbon nitride powder; dispersing a nickel source, hydrated terphenyl and carbon nitride powder in deionized water, performing ultrasonic dispersion, reacting under a sealing condition, centrifuging and washing to obtain the carbon nitride/MOFs composite material. The obtained composite material can be used as a photocatalyst to react to generate hydrogen peroxide under the condition of no sacrificial agent, thereby fully playing the role of C 3 N 4 And MOF, thereby effectively improving the efficiency of photocatalytic uranium reduction.
Description
Technical Field
The invention belongs to the technical field of photocatalysis, and particularly relates to synthesis and application of a carbon nitride/MOFs composite material.
Background
The nuclear energy is used as a clean and efficient energy source and is an important support for realizing the double-carbon target in China. The stable supply of the main fuel uranium is a precondition for realizing the long-term stable development of nuclear energy. In the exploitation and use process of uranium resources, uranium-containing wastewater can be generated, and uranium in the uranium-containing wastewater has heavy metal toxicity and radioactivity and can cause great threat to human bodies and the environment. Therefore, research on extraction and separation of uranium from uranium-containing wastewater is paid attention to by researchers. Among the numerous removal methods, the photocatalytic method is capable of solidifying soluble hexavalent uranyl ions into uranium oxides, thereby achieving the objective of removing uranium from water. The existing photocatalyst has the defects of low photocatalysis efficiency, need of nitrogen atmosphere protection and the like, and in addition, a sacrificial agent such as methanol and the like is added in the photocatalysis process to realize the efficient removal of uranium, so that the difficulty of practical application is greatly increased.
Researches show that hydrogen peroxide generated by adding a proper catalyst can be combined with uranyl ions to generate water filament uranium ores in an air atmosphere, so that the solidification of the uranyl ions is realized, and the purpose of removing uranium is achieved. Among the numerous catalysts for the production of hydrogen peroxide, carbon nitride (C 3 N 4 ) There is a great interest in having excellent chemical stability, special electronic structure, and the like. However, conventional C 3 N 4 The light utilization rate is low, and the addition of a sacrificial agent is required.
Disclosure of Invention
Based on C 3 N 4 The invention provides synthesis and application of a carbon nitride/MOFs composite material, which is used as a photocatalyst for photocatalytic reduction of uranium.
In order to achieve the above purpose, the present invention proposes the following technical scheme:
a synthesis method of a carbon nitride/MOFs composite material comprises the following steps:
mixing urea, melamine, sodium hydroxide and potassium chloride, calcining in a tube furnace under inert atmosphere, centrifuging with pure water, washing, and drying to obtain carbon nitride powder;
dispersing nickel source, 2,3,6,7,10, 11-hexahydroxytriphenyl (HHTP) and carbon nitride powder in deionized water, uniformly dispersing by ultrasonic, placing the mixture into a polytetrafluoroethylene sealed autoclave, reacting in an oven, centrifuging after the reaction, and washing with deionized water to obtain a carbon nitride/MOFs composite material (marked as C) 3 N 4 -MOF)。
Further, the mass ratio of urea, melamine, sodium hydroxide and potassium chloride is 1.5:1.5:0.2:7.5.
Further, the calcination temperature was 550℃and the calcination time was 4 hours.
Further, the nickel source is nickel acetate tetrahydrate.
Further, the dosage ratio of the nickel source, 2,3,6,7,10, 11-hexahydroxytriphenyl, carbon nitride powder and deionized water is 80 mg/56 mg/60 mg/30 mL.
Further, the reaction temperature is 85 ℃ and the reaction time is 12h.
The invention also provides the carbon nitride/MOFs composite material synthesized by the synthesis method of the carbon nitride/MOFs composite material.
The invention also provides application of the carbon nitride/MOFs composite material in treating uranium in wastewater.
The invention synthesizes C 3 N 4 The MOF composite is used for photocatalytic removal of uranium in aqueous solutions without a sacrificial agent. Specifically, a certain mass of C 3 N 4 And (3) placing the MOF composite material into uranium-containing solution, stirring and contacting for 1h in a dark box, then turning on a light source to perform photocatalysis reaction, sampling once at intervals in the process, measuring the concentration of residual uranyl ions in the solution, and verifying the removal performance of the composite material on the uranyl ions.
Compared with the prior art, the invention has the beneficial effects that:
the synthesis method provided by the invention has the advantages of simple and feasible process and mild conditions. The obtained composite material can be used as a photocatalyst to react to generate hydrogen peroxide under the condition of no sacrificial agent, thereby fully playing the role of C 3 N 4 And MOF, thereby effectively improving the efficiency of photocatalytic reduction of uranium, and no sacrificial agent is added in the reduction process. The composite material prepared by the invention has the advantages of high photocatalytic activity, low cost, easy acquisition, simple preparation, recoverability and the like.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is C 3 N 4 MOF and C 3 N 4 -SEM images of MOF composite; wherein (a) is C 3 N 4 The method comprises the steps of carrying out a first treatment on the surface of the (b) is MOF; (c) Is C 3 N 4 -MOF composite;
FIG. 2 is a MOF, C 3 N 4 C 3 N 4 -band structure diagram of MOF composite;
FIG. 3 is a MOF, C 3 N 4 C 3 N 4 Comparison of uranium photocatalytic Properties of MOF composite Material in the Presence and absence of sacrificial agent and H Generation 2 O 2 Content comparison; wherein (a) is a sacrificial agent of H 2 O 2 Influence of the photocatalytic performance of uranium content; (b) C in the presence of a sacrificial agent 3 N 4 -effect of MOF composite on uranium photocatalytic performance; (c) C without sacrificial agent 3 N 4 -effect of MOF composite on uranium photocatalytic performance;
FIG. 4 is C 3 N 4 -photocatalytic removal performance of the MOF composite material for uranium under different conditions;
FIG. 5 is C 3 N 4 -testing of the cycling stability and selective uranium removal of MOF composite photocatalytic uranium;
FIG. 6 is a different C without a sacrificial agent 3 N 4 -effect of MOF composite on uranium photocatalytic performance;
FIG. 7 is a different C without a sacrificial agent 3 N 4 C in an amount of 3 N 4 Effect of MOF composite on uranium photocatalytic performance.
Detailed Description
Various exemplary embodiments of the invention will now be described in detail, which should not be considered as limiting the invention, but rather as more detailed descriptions of certain aspects, features and embodiments of the invention.
It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. In addition, for numerical ranges in this disclosure, it is understood that each intermediate value between the upper and lower limits of the ranges is also specifically disclosed. Every smaller range between any stated value or stated range, and any other stated value or intermediate value within the stated range, is also encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded in the range.
Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference for the purpose of disclosing and describing the methods and/or materials associated with the documents. In case of conflict with any incorporated document, the present specification will control.
It will be apparent to those skilled in the art that various modifications and variations can be made in the specific embodiments of the invention described herein without departing from the scope or spirit of the invention. Other embodiments will be apparent to those skilled in the art from consideration of the specification of the present invention. The specification and examples are exemplary only.
As used herein, the terms "comprising," "including," "having," "containing," and the like are intended to be inclusive and mean an inclusion, but not limited to.
The term "room temperature" as used herein refers to 25℃unless otherwise specified.
The raw materials used in the invention, namely nickel acetate (AR 99%), 2,3,6,7,10, 11-hexahydroxytriphenyl (95%) are purchased from Shanghai Michelin Biochemical technology Co., ltd, urea (AR 99%), and melamine (99%) are purchased from Shanghai Aba Ding Shenghua technology Co., ltd.
The invention synthesizes a metal-organic framework (MOF) composite carbon nitride material, wherein the Ni-based MOF has the advantages of high porosity, adjustable structure, strong gas adsorption and the like, can assist carbon nitride to complete the reaction of generating hydrogen peroxide under the conditions of air atmosphere and no need of a sacrificial agent, and realizes the efficient removal of uranyl ions. The specific scheme is as follows:
a synthesis method of a carbon nitride/MOFs composite material comprises the following steps:
mixing urea, melamine, sodium hydroxide and potassium chloride, calcining in a tube furnace under inert atmosphere, centrifuging with pure water, washing, and drying to obtain carbon nitride powder;
dispersing nickel source, 2,3,6,7,10, 11-hexahydroxytriphenyl (HHTP) and carbon nitride powder in deionized water, uniformly dispersing by ultrasonic, placing the mixture into a polytetrafluoroethylene sealed autoclave, reacting in an oven, centrifuging after the reaction, and washing with deionized water to obtain a carbon nitride/MOFs composite material (marked as C) 3 N 4 -MOF)。
In some preferred embodiments, the mass ratio of urea, melamine, sodium hydroxide, and potassium chloride is 1.5:1.5:0.2:7.5.
In some preferred embodiments, the calcination temperature is 550 ℃ and the calcination time is 4 hours.
In some preferred embodiments, the nickel source is nickel acetate tetrahydrate.
In some preferred embodiments, the nickel source, 2,3,6,7,10, 11-hexahydroxytriphenyl, carbon nitride powder, and deionized water are used in a ratio of 80mg:56mg:60mg:30mL.
In some preferred embodiments, the reaction temperature is 85 ℃ and the reaction time is 12 hours.
The invention also provides the carbon nitride/MOFs composite material synthesized by the synthesis method of the carbon nitride/MOFs composite material.
The invention also provides application of the carbon nitride/MOFs composite material in treating uranium in wastewater.
The invention synthesizes C 3 N 4 The MOF composite is used for photocatalytic removal of uranium in aqueous solutions without a sacrificial agent. Specifically, a certain mass of C 3 N 4 Placing the MOF composite material into uranium-containing solution, stirring and contacting in a dark box for 1h, and performing photocatalytic reaction with a light sourceIn the process, sampling is carried out once at intervals, the concentration of residual uranyl ions in the solution is measured, and the removal performance of the composite material on the uranyl ions is verified.
Example 1
1) Preparation of carbon nitride powder: weighing urea (1.5 g), melamine (1.5 g), naOH (0.2 g) and KCl (7.5 g), grinding, mixing, transferring into a ceramic boat, and mixing under inert atmosphere (N) 2 ) Calcining in a tube furnace at 550deg.C for 4 hr, centrifuging with pure water, washing, and vacuum drying to obtain carbon nitride powder (C) 3 N 4 )。
2) Preparation of MOF: weighing Ni (OAC) 2 ·4H 2 O (0.32 mmol) and HHTP (0.168 mmol) were dissolved in 30mL deionized water and stirred for 30min; and transferring the mixture into a stainless steel water thermal reaction kettle with a polytetrafluoroethylene lining, reacting for 12 hours at 85 ℃, naturally cooling to room temperature after the reaction is finished, taking out the reacted solution and solid, and obtaining the MOF through centrifugation and washing with deionized water.
3)C 3 N 4 Preparation of MOF:
weighing Ni (OAC) 2 ·4H 2 O(0.32mmol)、HHTP(0.168mmol)、C 3 N 4 (60 mg) was dissolved in 30mL of deionized water and stirred for 30min; transferring the mixture into a stainless steel water thermal reaction kettle with polytetrafluoroethylene lining, reacting at 85deg.C for 12 hr, naturally cooling to room temperature after the reaction, taking out the reacted solution and solid, centrifuging, and washing with deionized water to obtain carbon nitride/MOFs composite material (denoted as C 3 N 4 -MOF)。
FIG. 1 is an SEM image of a different material, wherein (a) in FIG. 1 is C 3 N 4 As can be seen from the SEM image of (C) 3 N 4 Having a typical block-like structure; in FIG. 1, (b) is an SEM image of MOF, it can be seen that MOF has rod-like structures of different lengths and widths of about 50 nm; in FIG. 1, (C) is C 3 N 4 SEM images of MOF, it can be seen that MOF is at C 3 N 4 Staggered in the structure of (C) 3 N 4 Is a block-like structure.
FIG. 2 is a MOF, C 3 N 4 C 3 N 4 Band structure of MOF composite. Theoretically, semiconductors can be enriched from O by photocatalysis 2 H of (2) 2 H is generated in O 2 O 2 . Photogenerated valence band aperture (VB h) + ) Oxidizing water to form O 2 While conduction band electrons (CBe) - ) Promote O 2 Is reduced by two electrons to generate H 2 O 2 。MOF、C 3 N 4 The conduction band energy ratio O of (2) 2 /H 2 O 2 More negative (+0.68V) that is capable of O 2 Is reduced to H by double electron 2 O 2 。C 3 N 4 The valence band energy of 2.08V, higher than that of oxidation of water to O 2 Can perform photocatalytic oxidation of water. However, the valance band energy of MOF is only 1.19V, which is insufficient to oxidize water. C (C) 3 N 4 the-MOF composite material not only can carry out O 2 Is reduced to H by double electron 2 O 2 And at the same time can oxidize water to O 2 . And compared with C 3 N 4 The band gap width is reduced, the light absorption range is enlarged, and the recombination rate of electron holes is reduced.
Application example 1
1. Taking MOF and C 3 N 4 C 3 N 4 30mg of each MOF composite material is put into 50mL of pure water (2 mL of methanol is selectively added as a sacrificial agent), and after being uniformly dispersed, the MOF composite material is put into a photoreaction box, and ultraviolet light and visible light are obtained by using a 500w xenon lamp. Taking samples at intervals of 20min under light irradiation, and using TiSO 4 Measurement of H by method 2 O 2 Yield. After each sampling, 1mL of TiSO was added to the sample 4 And 2mLNH 3 .H 2 O was mixed, and a pale yellow flocculent precipitate was found to be formed at this time. Centrifuging in a centrifuge, removing supernatant, adding 5mL H 2 SO 4 Dissolving the precipitate. Finally, the absorbance was measured at 415 nm. As a result of the experiment, as shown in FIG. 3 (a), it can be seen that C 3 N 4 Photocatalytic precipitation of H in the absence of methanol addition to the MOF composite 2 O 2 The rate reaches 1.02mmol h -1 g -1 AboutC 3 N 4 About 10 times of the total number of the components. Due to the rapid electron-hole recombination, the MOF showed only 0.021mmol h -1 g -1 H of (2) 2 O 2 The amount of production. And after methanol is added as a sacrificial agent, three materials are used for photocatalysis H 2 O 2 The amount of production is increased. From this, it can be seen that C 3 N 4 The MOF composite has excellent photocatalytic properties.
2. MOF, C 3 N 4 C 3 N 4 The MOF composite material is used for removing uranium through photocatalysis, dark reaction is carried out for 1h under the condition of avoiding light, and then ultraviolet light and visible light are obtained in a photoreaction box by utilizing a 500w xenon lamp. Samples were taken at 20 minute intervals under light irradiation, and the absorbance was measured at 652nm with an azo arsine III developer. As a result of the experiment, as shown in FIG. 3 (b), it can be seen that the MOF and C 3 N 4 A space-time white comparison experiment with methanol as a sacrificial agent was performed to observe MOF and C 3 N 4 All have good adsorption performance, and C is obtained after 20min of light opening 3 N 4 The efficiency of uranium removal of the MOF composite is up to 95% or more. Following a comparative experiment of three materials in the absence of a sacrificial agent, as in FIG. 3 (C), it was found that after the two were compounded together, C 3 N 4 The photocatalytic degradation rate of the MOF composite material to uranium is obviously improved, and the removal rate of U (VI) after 1h of irradiation is up to 90%. The synergistic effect plays an important role in the process of removing uranium by photocatalysis, and further proves that C 3 N 4 Successful preparation of MOF composites.
3. By C 3 N 4 The MOF composite was subjected to batch photocatalytic experiments.
FIG. 4 (a) shows a different C 3 N 4 The photocatalytic performance test of the amount of MOF composite catalyst shows that with increasing catalyst amount, the efficiency is significantly improved, and peaks at 50 mg. However, as the mass increases, the higher the catalyst addition, the removal rate does not increase any more. It is presumed that the excessive catalyst acts as a light shielding barrier and shields the irradiation, thus, blockingThe effective light absorption of the catalyst is stopped.
Fig. 4 (b) shows the effect of the composite material on degradation of uranium solutions at different pH values, and it can be seen that 90% of U (VI) is removed after 60 minutes of irradiation at ph=5, and the removal performance is faster in a weak acid system. While little U (VI) is removed under strong acid conditions because U (VI) and H + Adsorption competition exists on the surface of the catalyst, and the active center of the catalyst is H + Occupying. On the other hand, under alkaline conditions, U (VI) will complex with carbonates and hydroxides, which will then electrostatically repel the negatively charged catalyst, thereby inhibiting the reduction reaction.
A dose of 30mg was selected and the photocatalytic reduction performance of U (VI) solutions of different concentrations was examined. As can be seen in fig. 4 (c), the rate of photocatalytic removal of uranium increases progressively with increasing uranium concentration. We found that more than 85% of U (VI) was removed after 60 minutes of irradiation at a concentration of 0.5 mM. This increase is due to U (VI) and C 3 N 4 The probability of MOF composite active site contact is greater.
In fig. 4, (d) shows the effect of temperature on catalytic performance, and it can be seen that as the temperature of the reaction system increases, the removal performance increases due to strong thermal motion. With the improvement of the electron transport efficiency, the reduction reaction is accelerated. It is speculated that increasing the temperature within a reasonable range facilitates the reduction reaction. However, when the temperature exceeds a reasonable range, the removal performance will deteriorate.
Application example 2
To further explore the C of the invention 3 N 4 The invention evaluates and tests the ion-selective properties and the recycling properties of the MOF composite. The specific experimental steps of the recycling performance test are as follows: the uranium solution is photo-catalyzed by the composite material, then the uranium solution is eluted by 0.1M nitric acid, and the uranium is photo-catalyzed by the composite material again, and the photo-catalytic performance of the uranium is observed after repeated times. As shown in the experimental result (b) in FIG. 5, it can be found that after recycling for 5 times, the photocatalytic performance of uranium is not obviously reduced, which indicates that the recycling performance of the material is excellentAnd the use cost of the method is further reduced, and the method is expected to be used for removing uranium in a practical environment.
The specific experimental steps of the selectivity evaluation are as follows: c (C) 3 N 4 The MOF composite material was photocatalytic with 0.4mM uranium solution, and ionic liquids (including La, zr, ce, cu, ba, zn) each at a concentration of 0.4mM were added, and their photocatalytic removal capacity for each ion was observed. As a result of the experiment, as shown in FIG. 5 (a), it can be seen that C 3 N 4 The MOF composite material has excellent selective removal capability for uranium, the selective removal efficiency is as high as more than 85%, and the removal efficiency of other ions is lower than 20%.
The above experimental results show that the C of the invention 3 N 4 The MOF composite material has low cost, the synthesis method is simple and quick, the excellent removal performance of uranium is shown under the condition of no addition of a sacrificial agent, the ion selectivity and the recycling performance are excellent, the cost of the material is further reduced, and a foundation is laid for practical application of the material.
Comparative example 1
The difference from example 1 is that the preparation method of carbon nitride is: weighing 5g of urea, grinding, mixing uniformly, transferring into a ceramic boat, and placing under inert atmosphere (N 2 ) Calcining in a tube furnace at 550deg.C for 4 hr, centrifuging with pure water, washing, and vacuum drying to obtain carbon nitride powder (C) 3 N 4 )。
Comparative example 2
The difference from example 1 is that the preparation method of carbon nitride is: weighing 5g of melamine, grinding, uniformly mixing, transferring into a ceramic boat, and carrying out treatment under an inert atmosphere (N 2 ) Calcining in a tube furnace at 550deg.C for 4 hr, centrifuging with pure water, washing, and vacuum drying to obtain carbon nitride powder (called melamine-C) 3 N 4 )。
Comparative example 3
The difference from example 1 is that the preparation method of carbon nitride is: weighing urea: melamine=5g:5g, and after grinding and mixing uniformly, transferred to a ceramic boat under an inert atmosphere (N 2 ) Calcining in a tubular furnace at 550deg.C for 4 hr, centrifuging with pure water, washing, and vacuum drying to obtainCarbon nitride powder (denoted as urea: melamine-C 3 N 4 )。
FIG. 6 shows the rate at which three carbon nitride and MOF composites prepared in comparative examples 1-3 degrade uranium in the absence of a sacrificial agent, and as a result, urea-C was found 3 N 4 -MOF and melamine-C 3 N 4 The uranium concentration of the MOF slightly decreases after 40min of light-on, no obvious effect on the degradation of the MOF is caused as the light-on time increases, and the uranium cannot be completely degraded. Urea melamine-C 3 N 4 The uranium degradation rate of the MOF after 3.5 hours of light is 80%, but the time is long. Therefore, three traditional carbon nitride and MOF composite materials can not achieve good effect in uranium degradation.
Comparative example 4
As in example 1, the difference is C 3 N 4 In the preparation of the-MOF, C 3 N 4 The dosage is 40mg and 80mg respectively.
As a result, as shown in FIG. 7, when C was synthesized 3 N 4 In the case of MOF composites, C 3 N 4 The dosage is different (40 mg, 60mg and 80 mg), and the efficiency of photocatalytic degradation of uranium is different in the absence of a sacrificial agent. When C 3 N 4 When the dosage is 40mg and 80mg, uranium cannot be completely degraded, and after 2 hours of light-on, the uranium concentration is not obviously changed. C (C) 3 N 4 The best effect is found when the amount is 60mg, which indicates C 3 N 4 The dosage plays a very important role in experiments.
The foregoing description of the preferred embodiments of the invention is not intended to limit the invention to the particular embodiments disclosed, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.
Claims (8)
1. The synthesis method of the carbon nitride/MOFs composite material is characterized by comprising the following steps of:
mixing urea, melamine, sodium hydroxide and potassium chloride, calcining in an inert atmosphere, centrifuging, washing and drying to obtain carbon nitride powder;
dispersing nickel source, 2,3,6,7,10, 11-hexahydroxytriphenyl and carbon nitride powder in deionized water, performing ultrasonic dispersion, reacting under a sealing condition, centrifuging, and washing to obtain the carbon nitride/MOFs composite material.
2. The method for synthesizing carbon nitride/MOFs composite according to claim 1, wherein the mass ratio of urea, melamine, sodium hydroxide and potassium chloride is 1.5:1.5:0.2:7.5.
3. The method for synthesizing carbon nitride/MOFs composite according to claim 1, wherein the calcination temperature is 550 ℃ and the calcination time is 4 hours.
4. The method of synthesizing carbon nitride/MOFs composite according to claim 1, wherein the nickel source is nickel acetate tetrahydrate.
5. The method of synthesizing carbon nitride/MOFs composite according to claim 1, wherein the nickel source, 2,3,6,7,10, 11-hexahydroxytriphenyl, carbon nitride powder, and deionized water are used in a ratio of 80mg:56mg:60mg:30ml.
6. The method for synthesizing carbon nitride/MOFs composite according to claim 1, wherein the reaction temperature is 85 ℃ and the reaction time is 12h.
7. A carbon nitride/MOFs composite synthesized by the synthesis method of the carbon nitride/MOFs composite according to any one of claims 1 to 6.
8. Use of the carbon nitride/MOFs composite material of claim 7 for treating uranium in wastewater.
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