WO2022077811A1 - Carbon nitride quantum dot/tungsten trioxide composite photocatalytic material and preparation method therefor - Google Patents

Carbon nitride quantum dot/tungsten trioxide composite photocatalytic material and preparation method therefor Download PDF

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WO2022077811A1
WO2022077811A1 PCT/CN2021/074887 CN2021074887W WO2022077811A1 WO 2022077811 A1 WO2022077811 A1 WO 2022077811A1 CN 2021074887 W CN2021074887 W CN 2021074887W WO 2022077811 A1 WO2022077811 A1 WO 2022077811A1
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tungsten trioxide
carbon nitride
nitride quantum
quantum dots
preparation
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周杰
朱蓓蓓
吴斌
姜敏
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南通职业大学
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    • B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
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    • B01J23/16—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
    • B01J23/24—Chromium, molybdenum or tungsten
    • B01J23/30—Tungsten
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    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/0009—Use of binding agents; Moulding; Pressing; Powdering; Granulating; Addition of materials ameliorating the mechanical properties of the product catalyst
    • B01J37/0027—Powdering
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    • B01J37/009—Preparation by separation, e.g. by filtration, decantation, screening
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    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/02—Impregnation, coating or precipitation
    • B01J37/0236—Drying, e.g. preparing a suspension, adding a soluble salt and drying
    • B—PERFORMING OPERATIONS; TRANSPORTING
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    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/02—Impregnation, coating or precipitation
    • B01J37/0238—Impregnation, coating or precipitation via the gaseous phase-sublimation
    • B—PERFORMING OPERATIONS; TRANSPORTING
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    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/02—Impregnation, coating or precipitation
    • B01J37/03—Precipitation; Co-precipitation
    • B01J37/031—Precipitation
    • B01J37/033—Using Hydrolysis
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    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/34—Irradiation by, or application of, electric, magnetic or wave energy, e.g. ultrasonic waves ; Ionic sputtering; Flame or plasma spraying; Particle radiation
    • B01J37/341—Irradiation by, or application of, electric, magnetic or wave energy, e.g. ultrasonic waves ; Ionic sputtering; Flame or plasma spraying; Particle radiation making use of electric or magnetic fields, wave energy or particle radiation
    • B01J37/343—Irradiation by, or application of, electric, magnetic or wave energy, e.g. ultrasonic waves ; Ionic sputtering; Flame or plasma spraying; Particle radiation making use of electric or magnetic fields, wave energy or particle radiation of ultrasonic wave energy
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F1/00—Treatment of water, waste water, or sewage
    • C02F1/30—Treatment of water, waste water, or sewage by irradiation
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00—Nature of the contaminant
    • C02F2101/10—Inorganic compounds
    • C02F2101/20—Heavy metals or heavy metal compounds
    • C02F2101/22—Chromium or chromium compounds, e.g. chromates
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00—Nature of the contaminant
    • C02F2101/30—Organic compounds
    • C02F2101/38—Organic compounds containing nitrogen
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2101/00—Nature of the contaminant
    • C02F2101/30—Organic compounds
    • C02F2101/40—Organic compounds containing sulfur
    • C—CHEMISTRY; METALLURGY
    • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
    • C02F2305/00—Use of specific compounds during water treatment
    • C02F2305/10—Photocatalysts

Definitions

  • the invention belongs to the technical field of preparation methods of semiconductor photocatalytic materials, and particularly relates to a carbon nitride quantum dot/tungsten trioxide composite photocatalytic material and a preparation method thereof.
  • photocatalytic technology uses green, environmentally friendly and inexhaustible solar energy as the energy source for the reaction, and does not require additional energy, which can effectively reduce energy consumption and save resources.
  • Degradation of organic matter, photolysis of water for hydrogen production, carbon dioxide reduction and organic reactions have been widely studied, and have broad application prospects and important research value.
  • tungsten trioxide As an important transition metal semiconductor material, tungsten trioxide has excellent properties such as high sensitivity, good gas sensitivity and good thermal stability, and has a wide range of raw material sources, low price, green and pollution-free, and has a wide range of applications in many fields.
  • tungsten trioxide also has some disadvantages, mainly because of the low conduction band and the large forbidden band width of tungsten trioxide. The lower position of the conduction band will lead to the inhibition of photo-generated holes during the photo-oxidation process, and at the same time, the utilization of sunlight by tungsten trioxide is not high.
  • the photogenerated hole-electron recombination probability in tungsten trioxide is high, resulting in a low quantum yield. Therefore, in the research process of tungsten trioxide, modification is needed to improve its photocatalytic performance.
  • graphitic carbon nitride As a metal-free material, graphitic carbon nitride has the advantages of low cost, green environmental protection, adjustable chemical composition, energy band structure and chemical stability. It has shown excellent performance in the field of photocatalysis and has become a major research hotspot in the field of photocatalysis. Although graphitic carbon nitride has attracted much attention as a catalyst, its large macroscopic size, high recombination rate of photogenerated electron-hole pairs, and low quantum yield and electrical conductivity limit its wide application in various fields.
  • Carbon nitride quantum dots not only have the properties of bulk carbon nitride, but also have unique physicochemical properties of quantum dots, which can provide a large number of active sites, and can also be effectively compounded with other materials or doped in some special structures. material inside.
  • Chinese Patent No. 201810037542.4 discloses a ZnS micro-composite material modified by graphene nitrogen carbide quantum dots and its preparation method and application, which belongs to the technical field of semiconductor composite materials, and provides a solution to the problem that g-C3N4 quantum dots are easy to agglomerate and the preparation method is complicated The problem.
  • Chinese patent 201810764098.6 discloses a preparation method of carbon nitride quantum dots/titanium dioxide sol, and the degradation rate of this material to methyl orange is 2.53 times that of commercially available P25.
  • the technical problem to be solved by the present invention is to provide a carbon nitride quantum dot/tungsten trioxide composite photocatalytic material and a preparation method thereof, wherein one-dimensional tungsten trioxide nanorods are modified with zero-dimensional quantum dots to realize the directional separation of charge space, Improve the separation efficiency of tungsten trioxide photogenerated carriers, reduce the recombination probability of holes and photogenerated electrons, and at the same time realize the controllability of the photoresponse range of tungsten trioxide, expand the photoresponse range of photocatalytic materials, and improve the photocatalyst. photocatalytic activity.
  • embodiments of the present invention provide a carbon nitride quantum dot/tungsten trioxide composite photocatalytic material, which is a dense heterojunction structure formed by carbon nitride quantum dots supported on the surface of tungsten trioxide.
  • the embodiment of the present invention also provides a preparation method of carbon nitride quantum dot/tungsten trioxide composite photocatalytic material, comprising the following steps:
  • Preparation of carbon nitride quantum dots weigh sodium citrate and urea in a certain molar ratio, dissolve in deionized water after grinding, disperse by ultrasonic, transfer to a hydrothermal kettle for reaction, and filter through a 0.22 ⁇ m microfiltration membrane after cooling , dialyzed, and freeze-dried to obtain carbon nitride quantum dots;
  • step (3) take by weighing a certain amount of the carbon nitride quantum dots obtained by step (1) and make a solution, add the tungsten trioxide nanorods obtained by step (2), stir, and ultrasonically disperse them into a hydrothermal still to react, After cooling, the sample is freeze-dried and vacuum-dried to obtain a carbon nitride quantum dot/tungsten trioxide composite photocatalytic material.
  • step (1) the molar ratio of sodium citrate and urea is 2-8:1.
  • step (1) the reaction temperature in the hydrothermal kettle is 160-200° C., and the reaction time is 0.5-4h.
  • step (1) the dialysis time is 12-48h.
  • the pH value of the acid adjustment solution used in step (2) is 1-3.
  • step (2) the reaction temperature in the hydrothermal kettle is 160-200°C, and the reaction time is 12-48h.
  • step (2) the drying temperature is 80-160° C., and the drying time is 24-48 h.
  • step (3) the mass ratio of carbon nitride quantum dots and tungsten trioxide nanorods is 1-20:100.
  • step (3) the reaction temperature in the hydrothermal kettle is 80-120° C., and the reaction time is 1-12h.
  • step (3) the vacuum drying temperature is 50-60° C., and the vacuum drying time is 12-24 h.
  • the present invention uses zero-dimensional quantum dots to modify one-dimensional tungsten trioxide nanorods, realizes the directional separation of charge space, improves the separation efficiency of tungsten trioxide photogenerated carriers, and reduces hole-
  • the recombination probability of photogenerated electrons can also realize the controllability of the photoresponse range of tungsten trioxide, expand the photoresponse range of the photocatalytic material, and improve the photocatalytic activity of the photocatalyst.
  • Fig. 1 is the XRD pattern of the sample obtained in Example 1 of the present invention.
  • Fig. 2 is the TEM image of the sample obtained in Example 1 of the present invention.
  • Fig. 3 is the XPS spectrogram of the obtained sample of the embodiment of the present invention 1;
  • FIG. 4 is the UV-visDRS spectrum of the sample obtained in Example 1 of the present invention.
  • the invention provides a carbon nitride quantum dot/tungsten trioxide composite photocatalytic material and a preparation method thereof.
  • the carbon nitride quantum dot/tungsten trioxide composite photocatalytic material is formed by supporting carbon nitride quantum dots on the surface of tungsten trioxide.
  • the dense heterojunction structure, its preparation method comprises the following steps:
  • Preparation of carbon nitride quantum dots weigh sodium citrate and urea in a certain molar ratio, dissolve in deionized water after grinding, disperse by ultrasonic, transfer to a hydrothermal kettle for reaction, and the reaction temperature is 160-200 ° C. The time is 0.5-4h, then cooled and filtered through a 0.22 ⁇ m microfiltration membrane, dialyzed for 12-48h, and freeze-dried to obtain carbon nitride quantum dots;
  • the molar ratio of sodium citrate and urea is 2-8:1.
  • the pH value of the acid adjustment solution used in this step is 1-3.
  • step (3) Weigh a certain amount of carbon nitride quantum dots obtained by step (1) and make a solution, add the tungsten trioxide nanorods obtained in step (2), the quality of carbon nitride quantum dots and tungsten trioxide nanorods
  • the ratio is 1-20:100, stir, ultrasonically disperse and then put into a hydrothermal kettle for reaction, the reaction temperature is 80-120 ° C, the reaction time is 1-12 h, the reaction is cooled, the sample is freeze-dried, and the environment is 50-60 ° C.
  • the carbon nitride quantum dot/tungsten trioxide composite photocatalytic material is obtained after drying under vacuum for 12-24 hours.
  • the present invention adopts the D8Advance X-ray diffractometer of German Bruker Spectrum Instrument Company to carry out X-ray diffraction analysis and test on the carbon nitride quantum dot/tungsten trioxide composite photocatalyst prepared by the present invention, and the XRD diffractogram is obtained as shown in Figure 1.
  • the diffraction peaks in Figure 1 are consistent with the standard PDF card (JCPDS Card No.85-2459) of hexagonal tungsten trioxide, and the diffraction peaks are at 13.8°, 23.4°, 24.2°, 27.3°, 28.0°, 33.9° and 36.8° They correspond to the (100), (002), (110), (102), (200), (112) and (202) crystal planes, respectively, while the diffraction peaks corresponding to the (002) crystal plane of carbon nitride quantum dots are the same as The diffraction peaks corresponding to the (101) crystal plane of tungsten trioxide coincide, and the content of carbon nitride quantum dots is relatively low, and the peaks are not obvious.
  • the present invention adopts the high-resolution field emission transmission electron microscope JEM-2100F of JEOL Ltd. to test the microstructure and crystal structure of the material, and the obtained photo is shown in FIG. 2 .
  • Figure 2a shows that the prepared tungsten trioxide has a short rod-like structure
  • Figure 2b is a TEM photo of the prepared carbon nitride quantum dots, and the main size of the quantum dots is between 3 and 8 nm
  • Figure 2c is a carbon nitride quantum dot/three TEM photo of tungsten oxide, it can be seen from the photo that carbon nitride quantum dots are successfully loaded on the surface of tungsten trioxide to form a dense heterojunction structure
  • Figure 2d is the FETEM photo of carbon nitride quantum dots/tungsten trioxide, photo It clearly shows that the lattice spacing of carbon nitride quantum dots is 0.34 nm, corresponding to its (002) crystal plane, and the lattice spacing of tungsten tri
  • the American Thermo Scientific EscaLab 250Xi X-ray photoelectron spectrometer is used to analyze the element composition and the chemical state of the element.
  • the samples showed diffraction peaks of W 4f, O 1s, C 1s and N 1s, indicating that the main constituent elements of the composite were W, O, C and N.
  • Figure 3a–d show the orbital maps of W 4f, O 1s, C 1s and N 1s, respectively. It can be seen from Figure 3a that the W element has two peaks at the binding energy of 34.9 eV and 37.1 eV, corresponding to W 4f 7/2 and W 4f 5/2 of W 6+ , respectively.
  • the present invention adopts the Lambda 650S ultraviolet-visible spectrophotometer (optical polytetrafluoroethylene coating) of American PE company to test the ultraviolet-visible diffuse reflection absorption spectrum, and the obtained spectrum is shown in Figure 4.
  • Figure 4 pure tungsten trioxide and carbon nitride quantum dots both absorb in the visible light region. After compounding, the absorption light range of tungsten trioxide is further expanded, thereby increasing the corresponding range of the composite material to the light range and improving the absorbance of light.

Abstract

Provided are a carbon nitride quantum dot/tungsten trioxide composite photocatalytic material and a preparation method therefor. The preparation method involves: preparing carbon nitride quantum dots and tungsten trioxide by means of a hydrothermal method, respectively, and then depositing the carbon nitride quantum dots on the surface of tungsten trioxide by means of hydrothermal deposition. The preparation steps are simple and the cost is low, the carbon nitride quantum dots and tungsten trioxide form a compact heterojunction structure, the directional separation of charge space is achieved, the separation efficiency of tungsten trioxide photon-generated carriers is improved, and the recombination probability of holes and photon-generated electrons is reduced; in addition, the controllability of the photo-response interval of tungsten trioxide can be achieved, the photo-response interval of the photocatalytic material is expanded, and the photocatalytic activity of a photocatalyst is improved. The prepared photocatalyst has a high degradation activity on rhodamine B and methyl orange, and can also achieve the efficient reduction of Cr(VI) to Cr(III).

Description

氮化碳量子点/三氧化钨复合光催化材料及其制备方法Carbon nitride quantum dots/tungsten trioxide composite photocatalytic material and preparation method thereof 技术领域technical field
本发明属于半导体光催化材料制备方法技术领域，具体涉及一种氮化碳量子点/三氧化钨复合光催化材料及其制备方法。The invention belongs to the technical field of preparation methods of semiconductor photocatalytic materials, and particularly relates to a carbon nitride quantum dot/tungsten trioxide composite photocatalytic material and a preparation method thereof.
背景技术Background technique
光催化技术作为一种化学处理方法中的新兴技术，采用绿色环保并且取之不尽用之不竭的太阳能作为反应的能量来源，不需要外加能量，能够有效地降低能耗，节约资源，在降解有机物、光解水制氢、二氧化碳还原及有机反应等领域得到广泛的研究，具有广阔的应用前景和重要的研究价值。As an emerging technology in chemical treatment methods, photocatalytic technology uses green, environmentally friendly and inexhaustible solar energy as the energy source for the reaction, and does not require additional energy, which can effectively reduce energy consumption and save resources. Degradation of organic matter, photolysis of water for hydrogen production, carbon dioxide reduction and organic reactions have been widely studied, and have broad application prospects and important research value.
三氧化钨作为一种重要的过渡金属半导体材料，具有灵敏度高、气敏性好和热稳定性好等优异性能，且原料来源广泛、价格低、绿色无污染，在众多领域有着广泛的应用。然而三氧化钨也存在一些缺点，主要是因为三氧化钨的导带较低而且禁带宽度较大。导带位置较低会导致光生空穴在光氧化过程中受到了抑制，同时，三氧化钨对太阳光的利用不高。另外，三氧化钨中光生空穴-电子的复合机率高，导致其量子产率较低。所以在三氧化钨的研究过程中，需要进行改性以提高其光催化性能。As an important transition metal semiconductor material, tungsten trioxide has excellent properties such as high sensitivity, good gas sensitivity and good thermal stability, and has a wide range of raw material sources, low price, green and pollution-free, and has a wide range of applications in many fields. However, tungsten trioxide also has some disadvantages, mainly because of the low conduction band and the large forbidden band width of tungsten trioxide. The lower position of the conduction band will lead to the inhibition of photo-generated holes during the photo-oxidation process, and at the same time, the utilization of sunlight by tungsten trioxide is not high. In addition, the photogenerated hole-electron recombination probability in tungsten trioxide is high, resulting in a low quantum yield. Therefore, in the research process of tungsten trioxide, modification is needed to improve its photocatalytic performance.
石墨相氮化碳作为一种无金属材料，具有成本低廉，绿色环保，具有可调控的化学组成和能带结构和化学稳定性，在光解水制氢、光催化降解有机物以及光催化反应等领域表现出优异的性能，成为光催化领域的一大研究热点。虽然石墨相氮化碳作为催化剂备受关注，但由于宏观尺寸较大，光生电子-空穴对的复合率较高，量子产率和导电率较低，限制了其在各领域的广泛应用。而氮化碳量子点，不仅具有块状氮化碳的性质，还具有量子点独特的物化性质，可以提供大量的活性位点，还能有效地与其他材料复合或掺杂在一些特殊结构的材料里面。As a metal-free material, graphitic carbon nitride has the advantages of low cost, green environmental protection, adjustable chemical composition, energy band structure and chemical stability. It has shown excellent performance in the field of photocatalysis and has become a major research hotspot in the field of photocatalysis. Although graphitic carbon nitride has attracted much attention as a catalyst, its large macroscopic size, high recombination rate of photogenerated electron-hole pairs, and low quantum yield and electrical conductivity limit its wide application in various fields. Carbon nitride quantum dots not only have the properties of bulk carbon nitride, but also have unique physicochemical properties of quantum dots, which can provide a large number of active sites, and can also be effectively compounded with other materials or doped in some special structures. material inside.
中国专利201810037542.4公开了一种石墨烯碳化氮量子点修饰的ZnS微 米复合材料及其制备方法和应用，属半导体复合材料技术领域，提供了一种解决g-C3N4量子点容易团聚、且制备方法复杂的问题。中国专利201810764098.6公开了一种氮化碳量子点/二氧化钛溶胶的制备方法，该材料对甲基橙的降解率是市售P25的2.53倍。Chinese Patent No. 201810037542.4 discloses a ZnS micro-composite material modified by graphene nitrogen carbide quantum dots and its preparation method and application, which belongs to the technical field of semiconductor composite materials, and provides a solution to the problem that g-C3N4 quantum dots are easy to agglomerate and the preparation method is complicated The problem. Chinese patent 201810764098.6 discloses a preparation method of carbon nitride quantum dots/titanium dioxide sol, and the degradation rate of this material to methyl orange is 2.53 times that of commercially available P25.
江苏大学的Wang Tao等(Spectrochimica Acta Part A:Molecular and Biomolecular Spectroscopy 213(2019)19–27)以氮化碳量子点修饰Bi2Ti2O7，对环丙沙星表现出极高的光催化活性。南昌航空大学的Ruobin Guo等(International Journal of Hydrogen Energy 45(2020)22534-22544)制备了氮化碳量子点修饰的二氧化碳纳米粒子异质结光催化材料，该材料可高效降解双酚A且能高效产氢。东莞理工学院的Weiqian Kong等(Adv.Mater.Interfaces 2018,1801653)以N掺杂的碳点改性三氧化钨纳米片，提高了材料的导电性和电化学性能。Wang Tao et al. from Jiangsu University (Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 213 (2019) 19–27) modified Bi2Ti2O7 with carbon nitride quantum dots, which showed extremely high photocatalytic activity towards ciprofloxacin. Ruobin Guo et al. (International Journal of Hydrogen Energy 45(2020)22534-22544) from Nanchang Aerospace University prepared carbon nitride quantum dots-modified carbon dioxide nanoparticle heterojunction photocatalytic materials, which can efficiently degrade bisphenol A and can Efficient hydrogen production. Weiqian Kong et al. (Adv.Mater.Interfaces 2018, 1801653) of Dongguan University of Technology modified tungsten trioxide nanosheets with N-doped carbon dots, which improved the electrical conductivity and electrochemical performance of the material.
迄今为止，尚未见以氮化碳量子点修饰三氧化钨制备氮化碳量子点/三氧化钨复合光催化材料的报道。So far, there have been no reports on the preparation of carbon nitride quantum dots/tungsten trioxide composite photocatalytic materials by modifying tungsten trioxide with carbon nitride quantum dots.
发明内容SUMMARY OF THE INVENTION
本发明要解决的技术问题是提供一种氮化碳量子点/三氧化钨复合光催化材料及其制备方法，以零维量子点修饰一维三氧化钨纳米棒，实现电荷空间的定向分离，提高三氧化钨光生载流子的分离效率，减少空穴-光生电子的复合几率，同时可实现三氧化钨光响应区间的可调控性，扩展光催化材料的光相应区间，提高了光催化剂的光催化活性。The technical problem to be solved by the present invention is to provide a carbon nitride quantum dot/tungsten trioxide composite photocatalytic material and a preparation method thereof, wherein one-dimensional tungsten trioxide nanorods are modified with zero-dimensional quantum dots to realize the directional separation of charge space, Improve the separation efficiency of tungsten trioxide photogenerated carriers, reduce the recombination probability of holes and photogenerated electrons, and at the same time realize the controllability of the photoresponse range of tungsten trioxide, expand the photoresponse range of photocatalytic materials, and improve the photocatalyst. photocatalytic activity.
为解决上述技术问题，本发明的实施例提供一种氮化碳量子点/三氧化钨复合光催化材料，为由氮化碳量子点负载于三氧化钨表面形成的致密的异质结结构。To solve the above technical problems, embodiments of the present invention provide a carbon nitride quantum dot/tungsten trioxide composite photocatalytic material, which is a dense heterojunction structure formed by carbon nitride quantum dots supported on the surface of tungsten trioxide.
本发明实施例还提供一种氮化碳量子点/三氧化钨复合光催化材料的制备方法，包括如下步骤：The embodiment of the present invention also provides a preparation method of carbon nitride quantum dot/tungsten trioxide composite photocatalytic material, comprising the following steps:
(1)制备氮化碳量子点：称取一定摩尔比的柠檬酸钠和尿素，研磨后溶于去离子水中，超声分散，转入水热釜中反应，冷却后经0.22μm微滤膜过滤，透析，冻干后得到氮化碳量子点；(1) Preparation of carbon nitride quantum dots: weigh sodium citrate and urea in a certain molar ratio, dissolve in deionized water after grinding, disperse by ultrasonic, transfer to a hydrothermal kettle for reaction, and filter through a 0.22 μm microfiltration membrane after cooling , dialyzed, and freeze-dried to obtain carbon nitride quantum dots;
(2)制备三氧化钨纳米棒：称取一定量的偏钨酸铵，研磨后溶于去离子水中，超声分散后，加入一定量的酸调节溶液为酸性，转入水热釜中反应，冷却后经水洗、醇洗各3次，干燥后得到三氧化钨纳米棒；(2) Preparation of tungsten trioxide nanorods: weigh a certain amount of ammonium metatungstate, dissolve it in deionized water after grinding, and after ultrasonic dispersion, add a certain amount of acid to adjust the solution to be acidic, and transfer it into a hydrothermal kettle to react, After cooling, the tungsten trioxide nanorods are obtained after washing with water and alcohol for 3 times respectively, and drying;
(3)称取一定量由步骤(1)所得的氮化碳量子点并配成溶液，加入步骤(2)所得的三氧化钨纳米棒，搅拌，超声分散后置入水热釜中反应，冷却，样品经冷冻干燥，真空干燥后得到氮化碳量子点/三氧化钨复合光催化材料。(3) take by weighing a certain amount of the carbon nitride quantum dots obtained by step (1) and make a solution, add the tungsten trioxide nanorods obtained by step (2), stir, and ultrasonically disperse them into a hydrothermal still to react, After cooling, the sample is freeze-dried and vacuum-dried to obtain a carbon nitride quantum dot/tungsten trioxide composite photocatalytic material.
其中，步骤(1)中，柠檬酸钠和尿素的摩尔比为2-8:1。Wherein, in step (1), the molar ratio of sodium citrate and urea is 2-8:1.
其中，步骤(1)中，水热釜中反应温度为160-200℃，反应时间为0.5-4h。Wherein, in step (1), the reaction temperature in the hydrothermal kettle is 160-200° C., and the reaction time is 0.5-4h.
其中，步骤(1)中，透析时间为12-48h。Wherein, in step (1), the dialysis time is 12-48h.
其中，步骤(2)中所用酸调节溶液的pH值为1-3。Wherein, the pH value of the acid adjustment solution used in step (2) is 1-3.
其中，步骤(2)中，水热釜中反应温度为160-200℃，反应时间为12-48h。Wherein, in step (2), the reaction temperature in the hydrothermal kettle is 160-200°C, and the reaction time is 12-48h.
其中，步骤(2)中，干燥温度为80-160℃，干燥时间为24-48h。Wherein, in step (2), the drying temperature is 80-160° C., and the drying time is 24-48 h.
其中，步骤(3)中，氮化碳量子点和三氧化钨纳米棒的质量比为1-20:100。Wherein, in step (3), the mass ratio of carbon nitride quantum dots and tungsten trioxide nanorods is 1-20:100.
其中，步骤(3)中，水热釜中反应温度为80-120℃，反应时间为1-12h。Wherein, in step (3), the reaction temperature in the hydrothermal kettle is 80-120° C., and the reaction time is 1-12h.
其中，步骤(3)中，真空干燥温度为50-60℃，真空干燥时间为12-24h。Wherein, in step (3), the vacuum drying temperature is 50-60° C., and the vacuum drying time is 12-24 h.
本发明的上述技术方案的有益效果如下：本发明以零维量子点修饰一维三氧化钨纳米棒，实现电荷空间的定向分离，提高三氧化钨光生载流子的分离效率，减少空穴-光生电子的复合几率，同时可实现三氧化钨光响应区间的可调控性，扩展光催化材料的光相应区间，提高了光催化剂的光催化活性。The beneficial effects of the above technical solutions of the present invention are as follows: the present invention uses zero-dimensional quantum dots to modify one-dimensional tungsten trioxide nanorods, realizes the directional separation of charge space, improves the separation efficiency of tungsten trioxide photogenerated carriers, and reduces hole- The recombination probability of photogenerated electrons can also realize the controllability of the photoresponse range of tungsten trioxide, expand the photoresponse range of the photocatalytic material, and improve the photocatalytic activity of the photocatalyst.
附图说明Description of drawings
图1为本发明实施例1所得样品的XRD图；Fig. 1 is the XRD pattern of the sample obtained in Example 1 of the present invention;
图2为本发明实施例1所得样品的TEM图；Fig. 2 is the TEM image of the sample obtained in Example 1 of the present invention;
图3为本发明实施例1所得样品的XPS谱图；Fig. 3 is the XPS spectrogram of the obtained sample of the embodiment of the present invention 1;
图4为本发明实施例1所得样品的UV–visDRS谱图。FIG. 4 is the UV-visDRS spectrum of the sample obtained in Example 1 of the present invention.
具体实施方式Detailed ways
为使本发明要解决的技术问题、技术方案和优点更加清楚，下面将结合附 图及具体实施例进行详细描述。In order to make the technical problems, technical solutions and advantages to be solved by the present invention more clear, the following will be described in detail with reference to the accompanying drawings and specific embodiments.
本发明提供一种氮化碳量子点/三氧化钨复合光催化材料及其制备方法，氮化碳量子点/三氧化钨复合光催化材料为由氮化碳量子点负载于三氧化钨表面形成的致密的异质结结构，其制备方法包括如下步骤：The invention provides a carbon nitride quantum dot/tungsten trioxide composite photocatalytic material and a preparation method thereof. The carbon nitride quantum dot/tungsten trioxide composite photocatalytic material is formed by supporting carbon nitride quantum dots on the surface of tungsten trioxide. The dense heterojunction structure, its preparation method comprises the following steps:
(1)制备氮化碳量子点：称取一定摩尔比的柠檬酸钠和尿素，研磨后溶于去离子水中，超声分散，转入水热釜中反应，反应温度为160-200℃，反应时间为0.5-4h，然后冷却后经0.22μm微滤膜过滤，透析12-48h，冻干后得到氮化碳量子点；(1) Preparation of carbon nitride quantum dots: weigh sodium citrate and urea in a certain molar ratio, dissolve in deionized water after grinding, disperse by ultrasonic, transfer to a hydrothermal kettle for reaction, and the reaction temperature is 160-200 ° C. The time is 0.5-4h, then cooled and filtered through a 0.22μm microfiltration membrane, dialyzed for 12-48h, and freeze-dried to obtain carbon nitride quantum dots;
其中，柠檬酸钠和尿素的摩尔比为2-8:1。Wherein, the molar ratio of sodium citrate and urea is 2-8:1.
(2)制备三氧化钨纳米棒：称取一定量的偏钨酸铵，研磨后溶于去离子水中，超声分散后，加入一定量的酸调节溶液为酸性，转入水热釜中反应，反应温度为160-200℃，反应时间为12-48h，然后冷却后经水洗、醇洗各3次，80-160℃环境下干燥24-48h后得到三氧化钨纳米棒；(2) Preparation of tungsten trioxide nanorods: weigh a certain amount of ammonium metatungstate, dissolve it in deionized water after grinding, and after ultrasonic dispersion, add a certain amount of acid to adjust the solution to be acidic, and transfer it into a hydrothermal kettle to react, The reaction temperature is 160-200°C, and the reaction time is 12-48h, then after cooling, washing with water and alcohol 3 times each, and drying at 80-160°C for 24-48h to obtain tungsten trioxide nanorods;
其中，本步骤中所用酸调节溶液的pH值为1-3。Wherein, the pH value of the acid adjustment solution used in this step is 1-3.
(3)称取一定量由步骤(1)所得的氮化碳量子点并配成溶液，加入步骤(2)所得的三氧化钨纳米棒，氮化碳量子点和三氧化钨纳米棒的质量比为1-20:100，搅拌，超声分散后置入水热釜中反应，反应温度为80-120℃，反应时间为1-12h，反应后冷却，样品经冷冻干燥，50-60℃环境下真空干燥12-24h后得到氮化碳量子点/三氧化钨复合光催化材料。(3) Weigh a certain amount of carbon nitride quantum dots obtained by step (1) and make a solution, add the tungsten trioxide nanorods obtained in step (2), the quality of carbon nitride quantum dots and tungsten trioxide nanorods The ratio is 1-20:100, stir, ultrasonically disperse and then put into a hydrothermal kettle for reaction, the reaction temperature is 80-120 ° C, the reaction time is 1-12 h, the reaction is cooled, the sample is freeze-dried, and the environment is 50-60 ° C. The carbon nitride quantum dot/tungsten trioxide composite photocatalytic material is obtained after drying under vacuum for 12-24 hours.
本发明所使用的试剂和原料如下文表1所示：The reagents and raw materials used in the present invention are shown in Table 1 below:
表1 本发明所使用的试剂和原料Table 1 Reagents and raw materials used in the present invention
Figure PCTCN2021074887-appb-000001
Figure PCTCN2021074887-appb-000001
Figure PCTCN2021074887-appb-000002
Figure PCTCN2021074887-appb-000002
下面结合具体实施例进一步阐述本发明的技术方案。The technical solutions of the present invention are further described below in conjunction with specific embodiments.
实施例1Example 1
称取1.01g柠檬酸钠和0.81g尿素，研磨30分钟后溶于60mL去离子水中，超声分散，转入水热釜中，180℃反应2h，冷却后经0.22μm微滤膜过滤，透析24h，冷冻干燥后得到氮化碳量子点。Weigh 1.01 g of sodium citrate and 0.81 g of urea, grind for 30 minutes, dissolve in 60 mL of deionized water, disperse by ultrasonic, transfer to a hydrothermal kettle, react at 180 °C for 2 hours, filter through a 0.22 μm microfiltration membrane after cooling, and dialyze for 24 hours , and carbon nitride quantum dots were obtained after freeze-drying.
称取3.5g偏钨酸铵，研磨后溶于50mL去离子水中，超声分散后，加入一定量的酸调节溶液pH为2，转入水热釜中180℃反应24h，冷却后经水洗、醇洗各3次，60℃下干燥后得到三氧化钨纳米棒。Weigh 3.5g of ammonium metatungstate, dissolve it in 50mL of deionized water after grinding, add a certain amount of acid to adjust the pH of the solution to 2 after ultrasonic dispersion, transfer it to a hydrothermal kettle for 24h reaction at 180°C, wash with water, alcohol after cooling After washing three times each, and drying at 60°C, tungsten trioxide nanorods were obtained.
称取0.05g氮化碳量子点加入100mL去离子水中，加入1g三氧化钨纳米棒，搅拌30min，超声分散后置入水热釜中120℃反应2h，冷却，样品经冷冻干燥，50℃下真空干燥后得到氮化碳量子点/三氧化钨复合光催化材料。Weigh 0.05g of carbon nitride quantum dots into 100mL of deionized water, add 1g of tungsten trioxide nanorods, stir for 30min, ultrasonically disperse, put them in a hydrothermal kettle for 2h reaction at 120°C, cool, and freeze-dried the sample at 50°C After vacuum drying, carbon nitride quantum dots/tungsten trioxide composite photocatalytic material is obtained.
取制备的催化剂0.1g，置于含有100mL、10mg/L的罗丹明B溶液的烧杯中，超声处理2min，暗吸附30min后，搅拌状态下由300W氙灯光源距离液面20cm处光照30min，降解后溶液经离心后由紫外-可见分光光度计测定其在554nm处的吸光度，经计算降解率C/C 0为97.5％。 Take 0.1 g of the prepared catalyst, put it in a beaker containing 100 mL, 10 mg/L of Rhodamine B solution, ultrasonically treat it for 2 min, and absorb it in the dark for 30 min. After the solution was centrifuged, its absorbance at 554 nm was measured by an ultraviolet-visible spectrophotometer, and the calculated degradation rate C/C 0 was 97.5%.
实施例2Example 2
称取1.01g柠檬酸钠和0.81g尿素，研磨30分钟后溶于60mL去离子水中，超声分散，转入水热釜中，180℃反应2h，冷却后经0.22μm微滤膜过滤，透析24h，冷冻干燥后得到氮化碳量子点。Weigh 1.01 g of sodium citrate and 0.81 g of urea, grind for 30 minutes, dissolve in 60 mL of deionized water, disperse by ultrasonic, transfer to a hydrothermal kettle, react at 180 °C for 2 hours, filter through a 0.22 μm microfiltration membrane after cooling, and dialyze for 24 hours , and carbon nitride quantum dots were obtained after freeze-drying.
称取3.5g偏钨酸铵，研磨后溶于50mL去离子水中，超声分散后，加入一定量的酸调节溶液pH为2，转入水热釜中180℃反应24h，冷却后经水洗、醇洗各3次，60℃下干燥后得到三氧化钨纳米棒。Weigh 3.5g of ammonium metatungstate, dissolve it in 50mL of deionized water after grinding, add a certain amount of acid to adjust the pH of the solution to 2 after ultrasonic dispersion, transfer it to a hydrothermal kettle for 24h reaction at 180°C, wash with water, alcohol after cooling After washing three times each, and drying at 60°C, tungsten trioxide nanorods were obtained.
称取0.05g氮化碳量子点加入100mL去离子水中，加入1g三氧化钨纳米棒，搅拌30min，超声分散后置入水热釜中120℃反应2h，冷却，样品经冷冻 干燥，50℃下真空干燥后得到氮化碳量子点/三氧化钨复合光催化材料。Weigh 0.05g of carbon nitride quantum dots into 100mL of deionized water, add 1g of tungsten trioxide nanorods, stir for 30min, ultrasonically disperse, put them into a hydrothermal kettle for 2h reaction at 120°C, cool, and freeze-dried the sample at 50°C. After vacuum drying, carbon nitride quantum dots/tungsten trioxide composite photocatalytic material is obtained.
取制备的催化剂0.1g，置于含有100mL、10mg/L的甲基橙溶液的烧杯中，超声处理2min，暗吸附30min后，搅拌状态下由300W氙灯光源距离液面20cm处光照30min，降解后溶液经离心后由紫外-可见分光光度计测定其在463nm处的吸光度，经计算降解率C/C 0为86.3％。 Take 0.1 g of the prepared catalyst, put it in a beaker containing 100 mL, 10 mg/L methyl orange solution, ultrasonically treat it for 2 min, and absorb it in the dark for 30 min. After the solution was centrifuged, its absorbance at 463 nm was measured by UV-Vis spectrophotometer, and the calculated degradation rate C/C 0 was 86.3%.
实施例3Example 3
称取1.01g柠檬酸钠和0.81g尿素，研磨30分钟后溶于60mL去离子水中，超声分散，转入水热釜中，180℃反应2h，冷却后经0.22μm微滤膜过滤，透析24h，冷冻干燥后得到氮化碳量子点。Weigh 1.01 g of sodium citrate and 0.81 g of urea, grind for 30 minutes, dissolve in 60 mL of deionized water, disperse by ultrasonic, transfer to a hydrothermal kettle, react at 180 °C for 2 hours, filter through a 0.22 μm microfiltration membrane after cooling, and dialyze for 24 hours , and carbon nitride quantum dots were obtained after freeze-drying.
称取3.5g偏钨酸铵，研磨后溶于50mL去离子水中，超声分散后，加入一定量的酸调节溶液pH为2，转入水热釜中180℃反应24h，冷却后经水洗、醇洗各3次，60℃下干燥后得到三氧化钨纳米棒。Weigh 3.5g of ammonium metatungstate, dissolve it in 50mL of deionized water after grinding, add a certain amount of acid to adjust the pH of the solution to 2 after ultrasonic dispersion, transfer it to a hydrothermal kettle for 24h reaction at 180°C, wash with water, alcohol after cooling After washing three times each, and drying at 60°C, tungsten trioxide nanorods were obtained.
称取0.05g氮化碳量子点加入100mL去离子水中，加入1g三氧化钨纳米棒，搅拌30min，超声分散后置入水热釜中120℃反应2h，冷却，样品经冷冻干燥，50℃下真空干燥后得到氮化碳量子点/三氧化钨复合光催化材料。Weigh 0.05g of carbon nitride quantum dots into 100mL of deionized water, add 1g of tungsten trioxide nanorods, stir for 30min, ultrasonically disperse, put them into a hydrothermal kettle for 2h reaction at 120°C, cool, and freeze-dried the sample at 50°C. After vacuum drying, carbon nitride quantum dots/tungsten trioxide composite photocatalytic material is obtained.
取制备的催化剂0.1g，置于含有100mL、20mg/L的Cr(VI)溶液的烧杯中，超声处理2min，暗吸附30min后，搅拌状态下由300W氙灯光源距离液面20cm处光照30min，降解后溶液经离心后根据二苯基碳酰肼法测定其在540nm处的吸光度，经计算Cr(VI)转化为Cr(III)的转化率为90.6％。Take 0.1 g of the prepared catalyst, put it in a beaker containing 100 mL, 20 mg/L of Cr(VI) solution, ultrasonically treat it for 2 min, and adsorb it in the dark for 30 min. After the solution was centrifuged, its absorbance at 540 nm was measured according to the diphenylcarbazide method, and the conversion rate of Cr(VI) to Cr(III) was calculated to be 90.6%.
实施例4Example 4
称取1.01g柠檬酸钠和0.81g尿素，研磨30分钟后溶于60mL去离子水中，超声分散，转入水热釜中，180℃反应2h，冷却后经0.22μm微滤膜过滤，透析24h，冷冻干燥后得到氮化碳量子点。Weigh 1.01 g of sodium citrate and 0.81 g of urea, grind for 30 minutes, dissolve in 60 mL of deionized water, disperse by ultrasonic, transfer to a hydrothermal kettle, react at 180 °C for 2 hours, filter through a 0.22 μm microfiltration membrane after cooling, and dialyze for 24 hours , and carbon nitride quantum dots were obtained after freeze-drying.
称取3.5g偏钨酸铵，研磨后溶于50mL去离子水中，超声分散后，加入一定量的酸调节溶液pH为2，转入水热釜中180℃反应24h，冷却后经水洗、醇洗各3次，60℃下干燥后得到三氧化钨纳米棒。Weigh 3.5g of ammonium metatungstate, dissolve it in 50mL of deionized water after grinding, add a certain amount of acid to adjust the pH of the solution to 2 after ultrasonic dispersion, transfer it to a hydrothermal kettle for 24h reaction at 180°C, wash with water, alcohol after cooling After washing three times each, and drying at 60°C, tungsten trioxide nanorods were obtained.
称取0.03g氮化碳量子点加入100mL去离子水中，加入1g三氧化钨纳米棒，搅拌30min，超声分散后置入水热釜中120℃反应2h，冷却，样品经冷冻干燥，50℃下真空干燥后得到氮化碳量子点/三氧化钨复合光催化材料。Weigh 0.03g of carbon nitride quantum dots into 100mL of deionized water, add 1g of tungsten trioxide nanorods, stir for 30min, ultrasonically disperse, put them in a hydrothermal kettle for 2h reaction at 120°C, cool, freeze-dry the sample, and store it at 50°C. After vacuum drying, carbon nitride quantum dots/tungsten trioxide composite photocatalytic material is obtained.
取制备的催化剂0.1g，置于含有100mL 10mg/L的罗丹明B溶液的烧杯中，超声处理2min，暗吸附30min后，搅拌状态下由300W氙灯光源距离液面20cm处光照30min，降解后溶液经离心后由紫外-可见分光光度计测定其在554nm处的吸光度，经计算降解率C/C 0为93.1％。 Take 0.1 g of the prepared catalyst, put it in a beaker containing 100 mL of 10 mg/L Rhodamine B solution, ultrasonically treat it for 2 min, and absorb it in the dark for 30 min. After centrifugation, the absorbance at 554 nm was measured by UV-Vis spectrophotometer, and the calculated degradation rate C/C 0 was 93.1%.
氮化碳量子点/三氧化钨复合光催化剂的表征Characterization of carbon nitride quantum dots/tungsten trioxide composite photocatalyst
本发明采用德国Bruker光谱仪器公司D8Advance型X射线衍射仪对本发明制备的氮化碳量子点/三氧化钨复合光催化剂进行X-射线衍射分析测试，得到XRD衍射图如图1所示，测试条件为：Cu靶Kα线，λ＝0.15406nm，2θ为10°～70°，扫描速度为5(°)/min。图1中衍射峰与六方晶型三氧化钨的标准PDF卡片(JCPDS Card No.85-2459)一致，衍射峰在13.8°、23.4°、24.2°、27.3°、28.0°、33.9°和36.8°分别对应(100)、(002)、(110)、(102)、(200)、(112)和(202)晶面，而氮化碳量子点的(002)晶面对应的衍射峰与三氧化钨的(101)晶面所对应的衍射峰重合，且氮化碳量子点的含量较低，其峰值并不明显。The present invention adopts the D8Advance X-ray diffractometer of German Bruker Spectrum Instrument Company to carry out X-ray diffraction analysis and test on the carbon nitride quantum dot/tungsten trioxide composite photocatalyst prepared by the present invention, and the XRD diffractogram is obtained as shown in Figure 1. The test conditions It is: Cu target Kα line, λ=0.15406nm, 2θ is 10°～70°, and scanning speed is 5(°)/min. The diffraction peaks in Figure 1 are consistent with the standard PDF card (JCPDS Card No.85-2459) of hexagonal tungsten trioxide, and the diffraction peaks are at 13.8°, 23.4°, 24.2°, 27.3°, 28.0°, 33.9° and 36.8° They correspond to the (100), (002), (110), (102), (200), (112) and (202) crystal planes, respectively, while the diffraction peaks corresponding to the (002) crystal plane of carbon nitride quantum dots are the same as The diffraction peaks corresponding to the (101) crystal plane of tungsten trioxide coincide, and the content of carbon nitride quantum dots is relatively low, and the peaks are not obvious.
本发明采用日本电子株式会社高分辨场发射透射电子显微镜JEM-2100F测试材料的显微结构和晶体结构，得到的照片如图2所示。图2a显示所制备的三氧化钨为短棒状结构；图2b为制备的氮化碳量子点的TEM照片，量子点的主要尺寸为3～8nm之间；图2c为氮化碳量子点/三氧化钨的TEM照片，从照片可以看出，氮化碳量子点成功负载于三氧化钨表面，形成致密的异质结结构；图2d为氮化碳量子点/三氧化钨的FETEM照片，照片中清晰显示氮化碳量子点的晶格间距为0.34nm，对应其(002)晶面，三氧化钨晶格间距为0.31nm，对应其(110)晶面。The present invention adopts the high-resolution field emission transmission electron microscope JEM-2100F of JEOL Ltd. to test the microstructure and crystal structure of the material, and the obtained photo is shown in FIG. 2 . Figure 2a shows that the prepared tungsten trioxide has a short rod-like structure; Figure 2b is a TEM photo of the prepared carbon nitride quantum dots, and the main size of the quantum dots is between 3 and 8 nm; Figure 2c is a carbon nitride quantum dot/three TEM photo of tungsten oxide, it can be seen from the photo that carbon nitride quantum dots are successfully loaded on the surface of tungsten trioxide to form a dense heterojunction structure; Figure 2d is the FETEM photo of carbon nitride quantum dots/tungsten trioxide, photo It clearly shows that the lattice spacing of carbon nitride quantum dots is 0.34 nm, corresponding to its (002) crystal plane, and the lattice spacing of tungsten trioxide is 0.31 nm, corresponding to its (110) crystal plane.
本发明采用美国赛默飞EscaLab 250Xi X射线光电子能谱仪对元素组成和元素的化学态进行分析。样品出现了W 4f、O 1s、C 1s和N 1s的衍射峰，说明了复合材料主要组成元素为W、O、C和N。图3a-d分别为W 4f、O 1s、 C 1s和N 1s的轨道图谱。从图3a可以看出，W元素在34.9eV和37.1eV结合能处有两个峰值，分别对应W 6+的W 4f 7/2和W 4f 5/2。从图3b可以看出，O元素在529.7eV和531.0eV结合能处的两个峰值，分别对应WO 3的W-O键和H 2O的H-O键。从图3c可以看出，C元素在284.5eV、286.0eV、288.0eV和289.8eV结合能处的四个峰值，分别对应sp2杂化的C-N键，sp3杂化C-N键，C-O键和C＝O。从图3d可以看出，N元素在39834eV、399.5eV和400.8eV结合能处的三个峰值，分别对应氨基的N-H键，三嗪环的C-N＝C键和N-(C) 3。综合XPS分析结果可知，氮化碳量子点已经成功沉积在三氧化钨表面形成氮化碳量子点/三氧化钨复合物。 In the present invention, the American Thermo Scientific EscaLab 250Xi X-ray photoelectron spectrometer is used to analyze the element composition and the chemical state of the element. The samples showed diffraction peaks of W 4f, O 1s, C 1s and N 1s, indicating that the main constituent elements of the composite were W, O, C and N. Figure 3a–d show the orbital maps of W 4f, O 1s, C 1s and N 1s, respectively. It can be seen from Figure 3a that the W element has two peaks at the binding energy of 34.9 eV and 37.1 eV, corresponding to W 4f 7/2 and W 4f 5/2 of W 6+ , respectively. It can be seen from Figure 3b that the two peaks of O element at the binding energy of 529.7 eV and 531.0 eV correspond to the WO bond of WO 3 and the HO bond of H 2 O, respectively. It can be seen from Figure 3c that the four peaks of C element at the binding energies of 284.5eV, 286.0eV, 288.0eV and 289.8eV correspond to sp2 hybridized CN bonds, sp3 hybridized CN bonds, CO bonds and C=O, respectively. . It can be seen from Figure 3d that the three peaks of N element at the binding energies of 39834 eV, 399.5 eV and 400.8 eV correspond to the NH bond of the amino group, the CN=C bond of the triazine ring and N-(C) 3 , respectively. Comprehensive XPS analysis results show that carbon nitride quantum dots have been successfully deposited on the surface of tungsten trioxide to form carbon nitride quantum dots/tungsten trioxide composites.
本发明采用美国PE公司的Lambda 650S紫外可见分光光度计(光学聚四氟乙烯涂层)测试紫外-可见漫反射吸收光谱，得到的谱图如图4所示。图4中，纯三氧化钨和氮化碳量子点在可见光区均有吸收，经复合后，三氧化钨的吸收光区间进一步得到拓展，从而增加了复合材料对光区间的相应范围，提高了光的吸收率。The present invention adopts the Lambda 650S ultraviolet-visible spectrophotometer (optical polytetrafluoroethylene coating) of American PE company to test the ultraviolet-visible diffuse reflection absorption spectrum, and the obtained spectrum is shown in Figure 4. In Figure 4, pure tungsten trioxide and carbon nitride quantum dots both absorb in the visible light region. After compounding, the absorption light range of tungsten trioxide is further expanded, thereby increasing the corresponding range of the composite material to the light range and improving the absorbance of light.
尽管已描述了本发明的优选实施例，但本领域内的技术人员一旦得知了基本创造性概念，则可对这些实施例作出另外的变更和修改。所以，所附权利要求意欲解释为包括优选实施例以及落入本发明范围的所有变更和修改。显然，本领域的技术人员可以对本发明进行各种改动和变型而不脱离本发明的精神和范围。这样，倘若本发明的这些修改和变型属于本发明权利要求及其等同技术的范围之内，则本发明也意图包含这些改动和变型在内。Although preferred embodiments of the present invention have been described, additional changes and modifications to these embodiments may occur to those skilled in the art once the basic inventive concepts are known. Therefore, the appended claims are intended to be construed to include the preferred embodiment and all changes and modifications that fall within the scope of the present invention. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention. Thus, provided that these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims (10)

  1. 一种氮化碳量子点/三氧化钨复合光催化材料，其特征在于，为由氮化碳量子点负载于三氧化钨表面形成的致密的异质结结构。A carbon nitride quantum dot/tungsten trioxide composite photocatalytic material is characterized in that it is a dense heterojunction structure formed by carbon nitride quantum dots supported on the surface of tungsten trioxide.
  2. 一种氮化碳量子点/三氧化钨复合光催化材料的制备方法，其特征在于，包括如下步骤：A preparation method of carbon nitride quantum dots/tungsten trioxide composite photocatalytic material, characterized in that it comprises the following steps:
    (1)制备氮化碳量子点：称取一定摩尔比的柠檬酸钠和尿素，研磨后溶于去离子水中，超声分散，转入水热釜中反应，冷却后经0.22μm微滤膜过滤，透析，冻干后得到氮化碳量子点；(1) Preparation of carbon nitride quantum dots: weigh sodium citrate and urea in a certain molar ratio, dissolve in deionized water after grinding, disperse by ultrasonic, transfer to a hydrothermal kettle for reaction, and filter through a 0.22 μm microfiltration membrane after cooling , dialyzed, and freeze-dried to obtain carbon nitride quantum dots;
    (2)制备三氧化钨纳米棒：称取一定量的偏钨酸铵，研磨后溶于去离子水中，超声分散后，加入一定量的酸调节溶液为酸性，转入水热釜中反应，冷却后经水洗、醇洗各3次，干燥后得到三氧化钨纳米棒；(2) Preparation of tungsten trioxide nanorods: weigh a certain amount of ammonium metatungstate, dissolve it in deionized water after grinding, and after ultrasonic dispersion, add a certain amount of acid to adjust the solution to be acidic, and transfer it into a hydrothermal kettle to react, After cooling, the tungsten trioxide nanorods are obtained after washing with water and alcohol for 3 times respectively, and drying;
    (3)称取一定量由步骤(1)所得的氮化碳量子点并配成溶液，加入步骤(2)所得的三氧化钨纳米棒，搅拌，超声分散后置入水热釜中反应，冷却，样品经冷冻干燥，真空干燥后得到氮化碳量子点/三氧化钨复合光催化材料。(3) take by weighing a certain amount of the carbon nitride quantum dots obtained by step (1) and make a solution, add the tungsten trioxide nanorods obtained by step (2), stir, and ultrasonically disperse them into a hydrothermal still to react, After cooling, the sample is freeze-dried and vacuum-dried to obtain a carbon nitride quantum dot/tungsten trioxide composite photocatalytic material.
  3. 根据权利要求2所述的氮化碳量子点/三氧化钨复合光催化材料的制备方法，其特征在于，步骤(1)中，柠檬酸钠和尿素的摩尔比为2-8:1。The preparation method of carbon nitride quantum dots/tungsten trioxide composite photocatalytic material according to claim 2, wherein, in step (1), the molar ratio of sodium citrate and urea is 2-8:1.
  4. 根据权利要求2所述的氮化碳量子点/三氧化钨复合光催化材料的制备方法，其特征在于，步骤(1)中，水热釜中反应温度为160-200℃，反应时间为0.5-4h。The preparation method of carbon nitride quantum dots/tungsten trioxide composite photocatalytic material according to claim 2, wherein in step (1), the reaction temperature in the hydrothermal kettle is 160-200°C, and the reaction time is 0.5 -4h.
  5. 根据权利要求2所述的氮化碳量子点/三氧化钨复合光催化材料的制备方法，其特征在于，步骤(1)中，透析时间为12-48h。The preparation method of carbon nitride quantum dots/tungsten trioxide composite photocatalytic material according to claim 2, wherein in step (1), the dialysis time is 12-48h.
  6. 根据权利要求2所述的氮化碳量子点/三氧化钨复合光催化材料的制备方法，其特征在于，步骤(2)中所用酸调节溶液的pH值为1-3。The preparation method of carbon nitride quantum dots/tungsten trioxide composite photocatalytic material according to claim 2, characterized in that the pH value of the acid adjustment solution used in step (2) is 1-3.
  7. 根据权利要求2所述的氮化碳量子点/三氧化钨复合光催化材料的制备方法，其特征在于，步骤(2)中，水热釜中反应温度为160-200℃，反应时间为12-48h。The preparation method of carbon nitride quantum dots/tungsten trioxide composite photocatalytic material according to claim 2, wherein in step (2), the reaction temperature in the hydrothermal kettle is 160-200° C., and the reaction time is 12 -48h.
  8. 根据权利要求2所述的氮化碳量子点/三氧化钨复合光催化材料的制备 方法，其特征在于，步骤(2)中，干燥温度为80-160℃，干燥时间为24-48h。The preparation method of carbon nitride quantum dots/tungsten trioxide composite photocatalytic material according to claim 2, characterized in that, in step (2), the drying temperature is 80-160°C, and the drying time is 24-48h.
  9. 根据权利要求2所述的氮化碳量子点/三氧化钨复合光催化材料的制备方法，其特征在于，步骤(3)中，氮化碳量子点和三氧化钨纳米棒的质量比为1-20:100。The preparation method of carbon nitride quantum dots/tungsten trioxide composite photocatalytic material according to claim 2, wherein in step (3), the mass ratio of carbon nitride quantum dots and tungsten trioxide nanorods is 1 -20:100.
  10. 根据权利要求2所述的氮化碳量子点/三氧化钨复合光催化材料的制备方法，其特征在于，步骤(3)中，水热釜中反应温度为80-120℃，反应时间为1-12h；The preparation method of carbon nitride quantum dots/tungsten trioxide composite photocatalytic material according to claim 2, wherein in step (3), the reaction temperature in the hydrothermal kettle is 80-120° C., and the reaction time is 1 -12h;
    步骤(3)中，真空干燥温度为50-60℃，真空干燥时间为12-24h。In step (3), the vacuum drying temperature is 50-60° C., and the vacuum drying time is 12-24 h.
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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114904550A (en) * 2022-05-18 2022-08-16 安徽大学 Method for efficiently preparing melamine self-assembled supramolecular material
CN115090314A (en) * 2022-05-26 2022-09-23 南京林业大学 0D/2D quantum dot/g-C 3 N 4 Photocatalyst and preparation method and application thereof
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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107456991A (en) * 2017-08-30 2017-12-12 江苏大学 A kind of g C3N4Quantum dot loads the preparation method of Bismuth tungstate nano-sheet photochemical catalyst
CN110252381A (en) * 2019-07-31 2019-09-20 泉州师范学院 A kind of preparation and application of 2D-2D tungstic acid/class graphite phase carbon nitride heterojunction structure photochemical catalyst
CN110479345A (en) * 2019-09-02 2019-11-22 中建材蚌埠玻璃工业设计研究院有限公司 A kind of g-C3N4The preparation method of the iron oxide photocatalyst of quantum dot modification
CN111715255A (en) * 2020-05-25 2020-09-29 黑龙江大学 Preparation method of Z-type photocatalyst
CN112121842A (en) * 2020-10-13 2020-12-25 南通职业大学 Carbon nitride quantum dot/tungsten trioxide composite photocatalytic material and preparation method thereof

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110052242B (en) * 2019-04-26 2021-09-03 黑龙江大学 Load carbon quantum dot/W18O49Preparation method of photocatalytic renewable porous carbon adsorbent

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107456991A (en) * 2017-08-30 2017-12-12 江苏大学 A kind of g C3N4Quantum dot loads the preparation method of Bismuth tungstate nano-sheet photochemical catalyst
CN110252381A (en) * 2019-07-31 2019-09-20 泉州师范学院 A kind of preparation and application of 2D-2D tungstic acid/class graphite phase carbon nitride heterojunction structure photochemical catalyst
CN110479345A (en) * 2019-09-02 2019-11-22 中建材蚌埠玻璃工业设计研究院有限公司 A kind of g-C3N4The preparation method of the iron oxide photocatalyst of quantum dot modification
CN111715255A (en) * 2020-05-25 2020-09-29 黑龙江大学 Preparation method of Z-type photocatalyst
CN112121842A (en) * 2020-10-13 2020-12-25 南通职业大学 Carbon nitride quantum dot/tungsten trioxide composite photocatalytic material and preparation method thereof

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
ZHU JIAN, WANG SONGLING, XIE SONGHAI, LI HEXING: "Hexagonal single crystal growth of WO3 nanorods along a [110] axis with enhanced adsorption capacity", CHEMICAL COMMUNICATIONS, ROYAL SOCIETY OF CHEMISTRY, UK, vol. 47, no. 15, 1 January 2011 (2011-01-01), UK , pages 4403 - 4405, XP055921131, ISSN: 1359-7345, DOI: 10.1039/c1cc00064k *

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CN115090314A (en) * 2022-05-26 2022-09-23 南京林业大学 0D/2D quantum dot/g-C 3 N 4 Photocatalyst and preparation method and application thereof
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