CN116920913A - Ethanol group and phosphate group co-modified carbon nitride photocatalyst and preparation method thereof - Google Patents
Ethanol group and phosphate group co-modified carbon nitride photocatalyst and preparation method thereof Download PDFInfo
- Publication number
- CN116920913A CN116920913A CN202310954633.5A CN202310954633A CN116920913A CN 116920913 A CN116920913 A CN 116920913A CN 202310954633 A CN202310954633 A CN 202310954633A CN 116920913 A CN116920913 A CN 116920913A
- Authority
- CN
- China
- Prior art keywords
- group
- ethanol
- carbon nitride
- aqueous solution
- urea
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical group CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 title claims abstract description 48
- 238000002360 preparation method Methods 0.000 title claims abstract description 15
- 239000011941 photocatalyst Substances 0.000 title abstract description 17
- -1 phosphate group co-modified carbon nitride Chemical class 0.000 title description 3
- 230000001699 photocatalysis Effects 0.000 claims abstract description 44
- 125000002467 phosphate group Chemical group [H]OP(=O)(O[H])O[*] 0.000 claims abstract description 35
- 239000001257 hydrogen Substances 0.000 claims abstract description 27
- 229910052739 hydrogen Inorganic materials 0.000 claims abstract description 27
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 claims abstract description 25
- 239000007864 aqueous solution Substances 0.000 claims abstract description 25
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 claims abstract description 21
- 239000004202 carbamide Substances 0.000 claims abstract description 21
- PVCJKHHOXFKFRP-UHFFFAOYSA-N N-acetylethanolamine Chemical compound CC(=O)NCCO PVCJKHHOXFKFRP-UHFFFAOYSA-N 0.000 claims abstract description 14
- 238000000034 method Methods 0.000 claims abstract description 12
- 238000003756 stirring Methods 0.000 claims abstract description 9
- ISIJQEHRDSCQIU-UHFFFAOYSA-N tert-butyl 2,7-diazaspiro[4.5]decane-7-carboxylate Chemical compound C1N(C(=O)OC(C)(C)C)CCCC11CNCC1 ISIJQEHRDSCQIU-UHFFFAOYSA-N 0.000 claims abstract description 9
- 238000001035 drying Methods 0.000 claims abstract description 8
- JMANVNJQNLATNU-UHFFFAOYSA-N oxalonitrile Chemical compound N#CC#N JMANVNJQNLATNU-UHFFFAOYSA-N 0.000 claims description 29
- 239000000463 material Substances 0.000 claims description 26
- 239000000843 powder Substances 0.000 claims description 19
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 16
- 238000010438 heat treatment Methods 0.000 claims description 15
- 239000002135 nanosheet Substances 0.000 claims description 11
- 239000007787 solid Substances 0.000 claims description 9
- 238000006243 chemical reaction Methods 0.000 claims description 7
- 238000001816 cooling Methods 0.000 claims description 7
- 238000005245 sintering Methods 0.000 claims description 7
- 239000008367 deionised water Substances 0.000 claims description 6
- 229910021641 deionized water Inorganic materials 0.000 claims description 6
- 238000000227 grinding Methods 0.000 claims description 3
- 239000011259 mixed solution Substances 0.000 claims description 3
- 239000004570 mortar (masonry) Substances 0.000 claims description 3
- 230000002195 synergetic effect Effects 0.000 claims description 3
- 238000005406 washing Methods 0.000 claims description 3
- 238000000354 decomposition reaction Methods 0.000 claims description 2
- 125000000524 functional group Chemical group 0.000 claims 1
- 238000004519 manufacturing process Methods 0.000 abstract description 19
- 239000000243 solution Substances 0.000 abstract description 10
- 230000031700 light absorption Effects 0.000 abstract description 8
- 239000003054 catalyst Substances 0.000 abstract description 7
- 238000001354 calcination Methods 0.000 abstract description 4
- 230000008569 process Effects 0.000 abstract description 4
- 238000004140 cleaning Methods 0.000 abstract 2
- 238000002156 mixing Methods 0.000 abstract 2
- 230000003197 catalytic effect Effects 0.000 abstract 1
- 230000000052 comparative effect Effects 0.000 description 14
- 238000007146 photocatalysis Methods 0.000 description 11
- 230000006798 recombination Effects 0.000 description 10
- 238000005215 recombination Methods 0.000 description 10
- 230000005540 biological transmission Effects 0.000 description 8
- 239000000969 carrier Substances 0.000 description 8
- 230000000694 effects Effects 0.000 description 7
- 230000009286 beneficial effect Effects 0.000 description 3
- 238000010571 fourier transform-infrared absorption spectrum Methods 0.000 description 3
- 125000001997 phenyl group Chemical group [H]C1=C([H])C([H])=C(*)C([H])=C1[H] 0.000 description 3
- 238000012546 transfer Methods 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 150000002431 hydrogen Chemical class 0.000 description 2
- 238000011068 loading method Methods 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical group [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 2
- 238000000985 reflectance spectrum Methods 0.000 description 2
- 239000002028 Biomass Substances 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical class [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 238000005033 Fourier transform infrared spectroscopy Methods 0.000 description 1
- 229910019142 PO4 Inorganic materials 0.000 description 1
- NBIIXXVUZAFLBC-UHFFFAOYSA-N Phosphoric acid Chemical group OP(O)(O)=O NBIIXXVUZAFLBC-UHFFFAOYSA-N 0.000 description 1
- GSEJCLTVZPLZKY-UHFFFAOYSA-N Triethanolamine Chemical compound OCCN(CCO)CCO GSEJCLTVZPLZKY-UHFFFAOYSA-N 0.000 description 1
- 238000000862 absorption spectrum Methods 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 125000003277 amino group Chemical group 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 150000001721 carbon Chemical group 0.000 description 1
- 239000002800 charge carrier Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 125000006575 electron-withdrawing group Chemical group 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000007306 functionalization reaction Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000011065 in-situ storage Methods 0.000 description 1
- 238000009830 intercalation Methods 0.000 description 1
- 230000002687 intercalation Effects 0.000 description 1
- 238000011031 large-scale manufacturing process Methods 0.000 description 1
- 230000001404 mediated effect Effects 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000002064 nanoplatelet Substances 0.000 description 1
- NBIIXXVUZAFLBC-UHFFFAOYSA-K phosphate Chemical compound [O-]P([O-])([O-])=O NBIIXXVUZAFLBC-UHFFFAOYSA-K 0.000 description 1
- 239000010452 phosphate Substances 0.000 description 1
- OJMIONKXNSYLSR-UHFFFAOYSA-N phosphorous acid Chemical group OP(O)O OJMIONKXNSYLSR-UHFFFAOYSA-N 0.000 description 1
- 238000013032 photocatalytic reaction Methods 0.000 description 1
- 238000002256 photodeposition Methods 0.000 description 1
- 238000006303 photolysis reaction Methods 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- 229910052573 porcelain Inorganic materials 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- 239000000376 reactant Substances 0.000 description 1
- 238000002407 reforming Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- PYWVYCXTNDRMGF-UHFFFAOYSA-N rhodamine B Chemical compound [Cl-].C=12C=CC(=[N+](CC)CC)C=C2OC2=CC(N(CC)CC)=CC=C2C=1C1=CC=CC=C1C(O)=O PYWVYCXTNDRMGF-UHFFFAOYSA-N 0.000 description 1
- 229940043267 rhodamine b Drugs 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 238000004904 shortening Methods 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- 229910052724 xenon Inorganic materials 0.000 description 1
- FHNFHKCVQCLJFQ-UHFFFAOYSA-N xenon atom Chemical compound [Xe] FHNFHKCVQCLJFQ-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- 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
-
- 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
- B01J31/00—Catalysts comprising hydrides, coordination complexes or organic compounds
- B01J31/02—Catalysts comprising hydrides, coordination complexes or organic compounds containing organic compounds or metal hydrides
- B01J31/0201—Oxygen-containing compounds
- B01J31/0202—Alcohols or phenols
-
- 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
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/08—Heat treatment
- B01J37/082—Decomposition and pyrolysis
-
- 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
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/28—Phosphorising
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B3/00—Hydrogen; Gaseous mixtures containing hydrogen; Separation of hydrogen from mixtures containing it; Purification of hydrogen
- C01B3/02—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen
- C01B3/04—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen by decomposition of inorganic compounds, e.g. ammonia
- C01B3/042—Decomposition of water
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Health & Medical Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Combustion & Propulsion (AREA)
- Inorganic Chemistry (AREA)
- Catalysts (AREA)
Abstract
The invention discloses a simple and low-cost g-C co-modified by ethanol groups and phosphate groups 3 N 4 The preparation method of the photocatalyst comprises the following steps: firstly, mixing urea with an aqueous solution of n-acetylethanolamine, stirring, centrifuging, cleaning, drying, calcining and the like to obtain UCN-NA modified by ethanol groups; mixing UCN-NA with phosphorous acid solution, stirring, centrifuging, cleaning, drying, and addingCalcining to obtain the g-C co-modified by ethanol group and phosphate group 3 N 4 A photocatalyst. The catalyst obtained by the invention has the advantages of wide light absorption range, high specific surface area and high catalytic activity, can realize high-efficiency photocatalytic hydrogen production and has stable performance when being applied to the photocatalytic hydrogen production process, and the preparation method has the advantages of simple process, convenient operation, easy realization of industrialization and higher practical value.
Description
Technical Field
The invention belongs to the technical field of photocatalysis, and relates to semiconductor lightThe catalyst specifically provides a g-C co-modified by ethanol groups and phosphate groups 3 N 4 A photocatalyst and a preparation method thereof belong to the technical field of photocatalysis hydrogen production.
Technical Field
Photocatalytic hydrogen production is considered as a promising solar energy utilization technology because solar energy stored in hydrogen molecules can be easily extracted, and water molecules generated in the combustion process are environmentally friendly. However, although related studies on photocatalysis have been conducted since the last 70 th century, it is currently difficult to industrially apply photocatalytic materials on a large scale due to the disadvantages of low efficiency, poor stability, and the like. Carbon nitride has been widely studied by researchers because of its advantages of no metal, low cost, simple synthesis, moderate energy band structure, etc.
However, the conventional process produces the bulk phase g-C 3 N 4 It has some disadvantages: such as small specific surface area, insufficient visible light absorption, high photo-generated electron-hole recombination rate, etc., which limit the practical application in the field of photocatalysis. Around the above-mentioned existing technical problems, researchers have adopted various approaches to improve the hydrogen production capability of photocatalytic materials. For example, increasing specific surface area, decreasing band gap, increasing charge mobility, decreasing charge carrier recombination rate, etc. To alleviate the above problems, literature (Q.Liu, L.L.Wei, Q.Y.xi, Y.Q.Lei, F.X.Wang, edge functionalization of terminal amino group in carbon nitride by in-site C-N coupling for photoreforming of biomass into H) 2 Chem, eng, j, 383 (2020), 123792.) discloses loading of an ethanol group to g-C by an in situ C-N coupling method 3 N 4 The photo-reforming performance is improved, but the problem of rapid recombination and small specific surface area of photo-generated carriers can not be solved by simply loading ethanol groups, so that the hydrogen production performance is still not ideal. Literature (W.Xing, C.Liu, H.Zhong, Y.Zhang, T.Zhang, C.Cheng, J.Han, G.Wu, G.Chen, photoshop group-mediated carriers transfer and energy band over carbon nitride for efficient photocatalytic H) 2 production and removal of rhodamine B J.Alloys Compd 895 (2022) 162772) discloses a kind ofNew strategies to build visible light driven phosphate-based intercalation g-C 3 N 4 Photocatalysts are capable of promoting photogenerated charge transfer and providing a large number of active reactive sites. However, although the hydrogen generating activity is improved as compared with the unmodified graphite phase carbon nitride, there is a problem that the number of available electrons is not sufficiently excited, and the overall effect is still to be enhanced. Therefore, the method for preparing the catalyst, which can comprehensively improve the composite efficiency of the carriers, enhance the light absorption capacity and optimize the energy band structure and simultaneously improve the carrier density, is still a difficult point of current research.
Disclosure of Invention
To solve the above problems, a first object of the present invention is to provide a g-C having excellent photocatalytic hydrogen production performance by synergistically modifying an ethanol group and a phosphate group 3 N 4 A method of photocatalyst. The ethanol group can be used as an electron withdrawing group, so that the band gap value is reduced, and the light absorption capacity is improved. Subsequent grafting of the phosphate groups onto g-C 3 N 4 In the layer, as a transmission channel of electrons, the transmission distance of carriers is greatly shortened, so that the recombination of photo-generated carriers is inhibited to a greater extent, and meanwhile, the formed nano-sheet structure can provide more reactive sites for photocatalytic reaction. Therefore, the high-efficiency photocatalytic hydrogen production performance is realized, and the basic g-C is solved 3 N 4 The material has the defects of high carrier recombination efficiency, limited number of reactive sites, insufficient light absorption capacity and the like.
A second object of the present invention is to provide a simple and low-cost process for preparing g-C co-modified with ethanol groups and phosphate groups 3 N 4 A method of photocatalyst.
A third object of the present invention is to provide a g-C co-modified with an ethanol group and a phosphate group 3 N 4 Application of photocatalyst in hydrogen production by photocatalytic water splitting, H in photocatalytic water splitting process 2 The yield can reach 72.17umol.
In order to achieve the technical aim, the invention provides a g-C co-modified by ethanol groups and phosphate groups 3 N 4 PhotocatalystIs characterized in that the method comprises the following steps:
step 1, preparation of UCN-NA:
1.1 dissolving urea (mass 20.0 g) in 30mL of deionized water to obtain an aqueous solution of urea; then 1mL of n-acetylethanolamine aqueous solution (the volume fraction of pure NA in water is 5%) is dispersed in urea aqueous solution to obtain aqueous solution of urea and n-acetylethanolamine;
1.2 stirring the aqueous solution of urea and n-acetylethanolamine for 30 minutes to obtain the aqueous solution of urea and n-acetylethanolamine which are uniformly mixed;
1.3 placing the obtained uniformly mixed aqueous solution in an oven at 60 ℃ for drying overnight to obtain white solid;
1.4 transferring the cooled solid into a mortar, carefully grinding the solid into powder, placing a powder sample into a muffle furnace, heating the powder sample to 550 ℃ at a heating rate of 5 ℃/min, preserving the temperature for 4 hours, and then naturally cooling the powder sample; and after the reaction is finished, sintering to obtain the carbon nitride photocatalytic material grafted with the ethanol functional group.
Step 2, preparation of P-UCN-NA:
2.1 dissolving 500mg of UCN-NA obtained in the step 1 in 30mL of deionized water, adding 1mL of phosphorous acid solution into the aqueous solution of UCN-NA, stirring the mixed solution for 6 hours, centrifuging, washing and drying to obtain a powder sample. Wherein the mass fraction of the phosphorous acid solution is 85%;
2.2, placing the powder sample in a muffle furnace, heating to 500 ℃ at a heating rate of 5 ℃/min, preserving heat for 2 hours, then naturally cooling to room temperature, and sintering to obtain the ethanol group and phosphate group co-modified carbon nitride photocatalytic material.
Compared with the prior art, the invention has the beneficial effects that:
(1) The invention provides g-C co-modified by ethanol group and phosphate group 3 N 4 The photocatalyst shows high activity of photocatalytic decomposition of water to produce hydrogen, and the synergistic capture and transmission distance shortening effects of the ethanol group and the phosphate group on photo-generated electron-hole further inhibit the bulk recombination and surface recombination of the ethanol group and the phosphate group, while the ethanol group is used as an electron donorThe carrier density can be further effectively improved, which means that more electrons reach the surface to combine with protons, thereby improving g-C 3 N 4 The hydrogen evolution rate of the photocatalysis hydrogen production catalyst, and the nano-sheet structure provides more active sites for the photocatalysis reaction, so that the photocatalysis reaction is enhanced. Solves the problems of the existing g-C 3 N 4 The material has the defects of high carrier recombination efficiency, limited active sites, poor light absorption capacity and the like.
(2) The invention provides g-C co-modified by ethanol group and phosphate group 3 N 4 The preparation method of the photocatalyst is simple, low in cost and beneficial to large-scale production.
(3) The invention provides g-C co-modified by ethanol group and phosphate group 3 N 4 Photocatalyst H in hydrogen production process by photocatalytic water splitting 2 The yield can reach 72.17 mu mol.
Drawings
FIG. 1 shows the co-modified g-C of the ethanol group and the phosphate group of the present invention 3 N 4 A synthetic mechanism diagram of the photocatalytic material.
FIG. 2 shows the co-modified g-C of the ethanol group and the phosphate group of the present invention 3 N 4 Scanning electron microscope photograph of the photocatalyst.
FIG. 3 shows the co-modified g-C of the ethanol group and the phosphate group of the present invention 3 N 4 Fourier transform infrared absorption spectrum (FTIR) of the photocatalyst.
FIG. 4 shows the co-modified g-C of the ethanol group and the phosphate group of the present invention 3 N 4 Ultraviolet visible diffuse reflectance spectrum of photocatalyst and corresponding Kubelka-Munk graph.
FIG. 5 shows the co-modified g-C of the ethanol group and the phosphate group of the present invention 3 N 4 g-C produced in a photocatalyst 3 N 4 Hydrogen evolution rate of the photocatalytic hydrogen-generating catalyst.
The specific description is as follows:
the objects, technical solutions and advantageous effects of the present invention will be described in further detail with reference to the examples and drawings, and it should be understood that the examples are intended to further illustrate the contents of the present invention and should not be construed as limiting the scope of the present invention in any sense.
Example 1:
this example provides a g-C co-modified with an ethanol group and a phosphate group 3 N 4 The photocatalytic material is characterized in that the carbon nitride is of a nano sheet structure; the carbon nitride is grafted with an ethanol group at the edge and is incorporated with a phosphate group in the layer, the ethanol functional group is used as an electron acceptor, and the phosphate group is inserted into the layer to be used as a transmission channel for electron transport; g-C co-modified by the ethanol group and the phosphate group 3 N 4 The photocatalytic material is obtained by a two-step calcination method, the formation mechanism of the photocatalysis of ethanol groups and phosphate groups is shown in figure 1, urea and n-acetylethanolamine are fully mixed, ethanol functional groups are introduced by the calcination method, the mixture is further reacted with a phosphorous acid solution, the morphology of the photocatalyst is changed to form nano sheets, and the phosphate groups are grafted at the same time.
More specifically, the preparation process of the porous flaky carbon nitride photocatalytic material comprises the following steps:
step 1, preparation of UCN-NA:
1.1 dissolving urea (mass 20.0 g) in 30mL of deionized water to obtain an aqueous solution of urea; then 1mL of n-acetylethanolamine aqueous solution (the volume fraction of pure NA in water is 5%) is dispersed in urea aqueous solution to obtain aqueous solution of urea and n-acetylethanolamine;
1.2 stirring the aqueous solution of urea and n-acetylethanolamine for 30 minutes to obtain the aqueous solution of urea and n-acetylethanolamine which are uniformly mixed;
1.3 placing the obtained uniformly mixed aqueous solution in an oven at 60 ℃ for drying overnight to obtain white solid;
1.4 transferring the cooled solid into a mortar, carefully grinding the solid into powder, placing a powder sample into a muffle furnace, heating the powder sample to 550 ℃ at a heating rate of 5 ℃/min, preserving the temperature for 4 hours, and then naturally cooling the powder sample; and after the reaction is finished, sintering to obtain the carbon nitride photocatalytic material grafted with the ethanol functional group.
Step 2, preparation of P-UCN-NA:
2.1 dissolving 500mg of UCN-NA obtained in the step 1 in 30mL of deionized water, adding 1mL of phosphorous acid solution into the aqueous solution of UCN-NA, stirring the mixed solution for 6 hours, centrifuging, washing and drying to obtain a powder sample. Wherein the mass fraction of the phosphorous acid solution is 85%;
2.2, placing the powder sample in a muffle furnace, heating to 500 ℃ at a heating rate of 5 ℃/min, preserving heat for 2 hours, then naturally cooling to room temperature, and sintering to obtain the nano flaky carbon nitride photocatalytic material.
Meanwhile, this example also provides comparative example 1 and comparative example 2; wherein, comparative example 1 is bulk phase carbon nitride, and the preparation process is as follows: placing urea (20.0 g) into a porcelain crucible with a cover, heating to 550 ℃ at a heating rate of 5 ℃/min, preserving heat for 4 hours, and then naturally cooling; after the reaction is finished, collecting a sample, and obtaining pale yellow powder after sintering, namely bulk phase carbon nitride. Comparative example 2 differs from example 1 in that: the UCN-NA prepared in the step 1 is directly heated to 550 ℃ from room temperature at a heating rate of 5 ℃/min, and is preserved at 550 ℃ for 2 h, so as to prepare the carbon nitride material;
the materials obtained in the above example 1 and comparative examples 1 to 2 were subjected to a photocatalytic hydrogen production experiment, and the specific steps were: 50mg of catalyst was dispersed in a quartz reactor containing 100 ml of triethanolamine solution (20 vol.%) and 1 wt.% chloroplatinic acid was added dropwise as cocatalyst, and N was introduced for 15 minutes 2 To discharge dissolved O from the solution 2 . The catalyst was subjected to photo-deposition of platinum by irradiation with a 300W xenon lamp for 1 hour while stirring continuously, and then the sample was tested for photo-decomposition rate of water to hydrogen, and hydrogen production was measured every 1 hour. The hydrogen production was measured by a gas chromatograph equipped with a thermal conductivity detector. The synergistic effect of the ethanol group and the phosphate group and the maximum improvement of the g-C can be obtained by the photocatalysis hydrogen production experiment 3 N 4 Is used for producing hydrogen by photocatalysis, H 2 The yield was up to 72.17umol.
FIG. 2 shows a Scanning Electron Microscope (SEM) of the materials prepared in example 1 and comparative examples 1-2, wherein FIG. 1 (a) is example 1, FIG. 2 (b) is comparative example 2, and FIG. 1 (c) is comparative example 1; as can be seen from the graph (c), the morphology of bulk carbon nitride prepared in comparative example 1 is in an agglomerated morphology, and the preparation method of two-step calcination utilizes the electron withdrawing effect of ethanol groups, and simultaneously acidizes the UCN-NA and the phosphorous acid solution through sufficient reaction, grafts the phosphate groups in the layer, and forms an electron transport and transmission channel, thus obtaining the nano flaky carbon nitride as shown in the graph (a) in example 1, which is greatly beneficial to exposing active sites.
FIG. 3 shows the Fourier transform infrared absorption spectra (FTIR) of the materials prepared in example 1 and comparative examples 1-2; as can be seen, example 1 and comparative examples 1-2 all show chemical structures similar to carbon nitride, but example 1 is at 1100-1200 cm -1 Peak enhancement in range, at about 1277cm -1 A new characteristic peak containing alcohol appears at 1075 cm -1 Characteristic peaks of phosphate groups appear, indicating that the ethanol groups and phosphate groups were successfully incorporated into the carbon nitride. About 1567cm -1 、1537 cm -1 、1426cm -1 、1328cm -1 Novel characteristic peaks containing benzene ring and-C (CH) 3 ) 3 It can be shown that the ethanol group is grafted on the carbon atom of the benzene ring, so that the asymmetrically embedded benzene ring is enhanced, the density of carriers is improved, and the charge transfer of the carbon nitride photocatalytic material is facilitated.
FIG. 4 shows the diffuse reflectance spectra of the materials prepared in example 1 and comparative examples 1-2; the material prepared in example 1 has the highest light absorption range and the highest light absorption intensity, which shows that the introduction of ethanol groups and phosphorous acid groups further reduces the band gap, improves the conductivity, inhibits the recombination of photo-generated electron-hole pairs, and thus improves the visible light photocatalysis efficiency of hydrogen evolution in the presence of a sacrificial agent.
FIG. 5 is a graph showing the photocatalytic hydrogen production performance of the materials prepared in example 1 and comparative examples 1 to 2 under the irradiation of visible light; as can be seen from the graph, the nano-sheet carbon nitride containing the ethanol group and the phosphate group prepared in example 1 exhibited significantly enhanced photocatalytic hydrogen production activity as compared to the bulk carbon nitride prepared in comparative example 1, and the hydrogen yield was highest among all samples; the enhancement of the photocatalytic activity shows that the ethanol group is used as an electron acceptor and the phosphoric acid group is used as a transmission channel for electron transport in the carbon nitride layer, so that the transmission distance of carriers is shortened, the carrier density is improved, the efficient intramolecular transmission of photo-generated carriers is promoted, and the problem of serious photo-generated carrier recombination in the carbon nitride is solved; at the same time, the nanoplatelet structure increases the chance of contact of the reactant with the active site.
While the invention has been described in terms of specific embodiments, any feature disclosed in this specification may be replaced by alternative features serving the equivalent or similar purpose, unless expressly stated otherwise; all of the features disclosed, or all of the steps in a method or process, except for mutually exclusive features and/or steps, may be combined in any manner.
Claims (3)
1. The ultrathin nano sheet photocatalytic material is characterized in that carbon nitride is of an ultrathin nano sheet structure, the carbon nitride is provided with an ethanol group and a phosphate group functional group, the ethanol group is used as an electron acceptor, and the phosphate group is inserted into an intermediate layer of the carbon nitride to form a vertical channel.
2. The ultra-thin nano-sheet carbon nitride photocatalytic material cooperatively modified by an ethanol group and a phosphate group according to claim 1, wherein the ultra-thin nano-sheet carbon nitride photocatalytic material cooperatively modified by the ethanol group and the phosphate group is used for photocatalytic decomposition of water to produce hydrogen under visible light.
3. A method for preparing the ultrathin nano-sheet photocatalytic material cooperatively modified by ethanol groups and phosphate groups according to claim 1, which is characterized by comprising the following steps:
step 1, preparation of UCN-NA:
1.1 dissolving urea (mass 20.0 g) in 30mL of deionized water to obtain an aqueous solution of urea; then 1mL of n-acetylethanolamine aqueous solution (the volume fraction of pure NA in water is 5%) is dispersed in urea aqueous solution to obtain aqueous solution of urea and n-acetylethanolamine;
1.2 stirring the aqueous solution of urea and n-acetylethanolamine for 30 minutes to obtain the aqueous solution of urea and n-acetylethanolamine which are uniformly mixed;
1.3 placing the obtained uniformly mixed aqueous solution in an oven at 60 ℃ for drying overnight to obtain white solid;
1.4 transferring the cooled solid into a mortar, carefully grinding the solid into powder, placing a powder sample into a muffle furnace, heating the powder sample to 550 ℃ at a heating rate of 5 ℃/min, preserving the temperature for 4 hours, and then naturally cooling the powder sample; after the reaction is finished, sintering to obtain a carbon nitride photocatalytic material grafted with ethanol functional groups;
step 2, preparation of P-UCN-NA:
2.1 dissolving 500mg of UCN-NA obtained in the step 2 in 30mL of deionized water, adding 1mL of phosphorous acid into the aqueous solution of UCN-NA, stirring the mixed solution for 6 hours, centrifuging, washing and drying to obtain a powder sample. Wherein the mass fraction of the phosphorous acid is 85%;
2.2, placing the powder sample in a muffle furnace, heating to 500 ℃ at a heating rate of 5 ℃/min, preserving heat for 2 hours, then naturally cooling to room temperature, and sintering to obtain the ethanol group and phosphate group synergistic modified ultrathin nano-sheet carbon nitride photocatalytic material.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310954633.5A CN116920913A (en) | 2023-08-01 | 2023-08-01 | Ethanol group and phosphate group co-modified carbon nitride photocatalyst and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310954633.5A CN116920913A (en) | 2023-08-01 | 2023-08-01 | Ethanol group and phosphate group co-modified carbon nitride photocatalyst and preparation method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116920913A true CN116920913A (en) | 2023-10-24 |
Family
ID=88384225
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310954633.5A Pending CN116920913A (en) | 2023-08-01 | 2023-08-01 | Ethanol group and phosphate group co-modified carbon nitride photocatalyst and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116920913A (en) |
-
2023
- 2023-08-01 CN CN202310954633.5A patent/CN116920913A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112169819B (en) | g-C 3 N 4 /(101)-(001)-TiO 2 Preparation method and application of composite material | |
| CN111437846B (en) | Porous CoO/CoP nanotube and preparation method and application thereof | |
| CN112517043B (en) | Nitrogen vacancy and hydroxyl synergistically modified graphite-phase carbon nitride photocatalyst, preparation method thereof and application thereof in photocatalytic hydrogen production | |
| CN112791730B (en) | Z-type nano-copper vanadate-based composite photocatalyst and preparation method and application thereof | |
| CN115069262B (en) | Oxygen vacancy modified MoO 3-x /Fe-W 18 O 49 Photocatalyst, preparation thereof and application thereof in nitrogen fixation | |
| CN112023974B (en) | P-CeO2/g-C3N4Heterojunction material, preparation method and application thereof | |
| CN110882714A (en) | Curled carbon nitride thin sheet, preparation method and application thereof in hydrogen production through photocatalytic water decomposition | |
| CN113751047A (en) | Covalent organic framework-carbon nitride nanosheet hybrid photocatalytic hydrogen evolution material and preparation method and application thereof | |
| CN108889325A (en) | A kind of synthetic method of Pt nanoparticle catalyst | |
| CN114210328B (en) | Rh monoatomic-modified PCN photocatalyst and preparation method and application thereof | |
| CN111974436B (en) | Graphite-phase carbon nitride and preparation method thereof, and method for producing hydrogen by photocatalytic water | |
| CN111644185A (en) | Bi stripping by cell crusher3O4Method for Cl and in photocatalytic reduction of CO2Application of aspects | |
| CN108620133B (en) | Preparation method and application of two-dimensional transverse polymer heterojunction visible light response catalytic hydrogen production material | |
| CN116393155A (en) | Carbocyclic doped g-C 3 N 4 Preparation method of heterojunction in basal plane and application of heterojunction in photo-reforming cellulose | |
| CN113697783B (en) | Porous g-C 3 N 4 Preparation method and application of nano-sheet | |
| CN116920913A (en) | Ethanol group and phosphate group co-modified carbon nitride photocatalyst and preparation method thereof | |
| CN116173987A (en) | CdIn 2 S 4 /CeO 2 Heterojunction photocatalyst, preparation method and application thereof | |
| CN112717958B (en) | Oxygen-rich vacancy BiOBr/HNb3O8Preparation method and application of nanosheet photocatalyst | |
| CN115090318A (en) | Preparation method and application of intermolecular heterojunction carbon nitride photocatalyst with high specific surface area | |
| CN111807336B (en) | Amorphous molybdenum oxide nanodot/two-dimensional carbon nitride nanosheet with photocatalysis and photothermal conversion performances and preparation method thereof | |
| CN111790423A (en) | Composite photocatalyst with edge-modified non-metallic functional group and preparation method and application thereof | |
| CN115814836B (en) | High-performance purple phosphazene/boron nitride aerogel composite photocatalytic material and preparation method and application thereof | |
| CN115845886B (en) | CdSe/MXene composite photocatalyst and preparation method and application thereof | |
| CN113755874B (en) | CoNi/C nano composite material, preparation method thereof and application thereof in synthesizing ammonia by electrocatalysis nitrogen fixation | |
| CN117599832A (en) | Tm/g-C 3 N 4 Nano composite photocatalyst, preparation method and application thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |