CN107321382B - Modified g-C3N4Photocatalyst and preparation method thereof - Google Patents
Modified g-C3N4Photocatalyst and preparation method thereof Download PDFInfo
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- 238000002360 preparation method Methods 0.000 title claims abstract description 12
- 239000011941 photocatalyst Substances 0.000 claims abstract description 35
- 238000006243 chemical reaction Methods 0.000 claims abstract description 29
- SMQUZDBALVYZAC-UHFFFAOYSA-N salicylaldehyde Chemical compound OC1=CC=CC=C1C=O SMQUZDBALVYZAC-UHFFFAOYSA-N 0.000 claims abstract description 28
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 5
- 229910002804 graphite Inorganic materials 0.000 claims abstract description 5
- 239000010439 graphite Substances 0.000 claims abstract description 5
- JDSHMPZPIAZGSV-UHFFFAOYSA-N melamine Chemical compound NC1=NC(N)=NC(N)=N1 JDSHMPZPIAZGSV-UHFFFAOYSA-N 0.000 claims abstract description 5
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical group CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 23
- 239000012279 sodium borohydride Substances 0.000 claims description 8
- 229910000033 sodium borohydride Inorganic materials 0.000 claims description 8
- 239000002904 solvent Substances 0.000 claims description 6
- 229920000877 Melamine resin Polymers 0.000 claims description 4
- 238000001354 calcination Methods 0.000 claims description 4
- 238000000034 method Methods 0.000 claims description 4
- 230000035484 reaction time Effects 0.000 claims description 4
- 239000000126 substance Substances 0.000 claims description 3
- 238000003837 high-temperature calcination Methods 0.000 claims description 2
- 239000003054 catalyst Substances 0.000 abstract description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 13
- 230000001699 photocatalysis Effects 0.000 abstract description 9
- 125000000524 functional group Chemical group 0.000 abstract description 3
- 238000007146 photocatalysis Methods 0.000 abstract description 2
- 239000002994 raw material Substances 0.000 abstract description 2
- 238000000197 pyrolysis Methods 0.000 abstract 1
- 239000011651 chromium Substances 0.000 description 28
- 239000000243 solution Substances 0.000 description 24
- 238000001179 sorption measurement Methods 0.000 description 14
- 238000012986 modification Methods 0.000 description 13
- 239000000047 product Substances 0.000 description 12
- 238000010438 heat treatment Methods 0.000 description 9
- 230000004048 modification Effects 0.000 description 9
- 238000010992 reflux Methods 0.000 description 9
- 238000006722 reduction reaction Methods 0.000 description 8
- 238000002474 experimental method Methods 0.000 description 7
- 150000002500 ions Chemical class 0.000 description 7
- JMANVNJQNLATNU-UHFFFAOYSA-N oxalonitrile Chemical compound N#CC#N JMANVNJQNLATNU-UHFFFAOYSA-N 0.000 description 7
- 230000009467 reduction Effects 0.000 description 6
- 238000010531 catalytic reduction reaction Methods 0.000 description 5
- 238000012512 characterization method Methods 0.000 description 5
- 239000003344 environmental pollutant Substances 0.000 description 5
- 239000011259 mixed solution Substances 0.000 description 5
- 231100000719 pollutant Toxicity 0.000 description 5
- 239000004065 semiconductor Substances 0.000 description 5
- 238000011161 development Methods 0.000 description 4
- 238000001035 drying Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 229910001385 heavy metal Inorganic materials 0.000 description 4
- 239000006228 supernatant Substances 0.000 description 4
- 238000005406 washing Methods 0.000 description 4
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 3
- 229910052755 nonmetal Inorganic materials 0.000 description 3
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N phenol group Chemical group C1(=CC=CC=C1)O ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 3
- 238000013032 photocatalytic reaction Methods 0.000 description 3
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 2
- 150000001299 aldehydes Chemical class 0.000 description 2
- 239000003638 chemical reducing agent Substances 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000003912 environmental pollution Methods 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- 239000001257 hydrogen Substances 0.000 description 2
- 238000002329 infrared spectrum Methods 0.000 description 2
- 229910052710 silicon Inorganic materials 0.000 description 2
- 239000010703 silicon Substances 0.000 description 2
- JYEUMXHLPRZUAT-UHFFFAOYSA-N 1,2,3-triazine Chemical group C1=CN=NN=C1 JYEUMXHLPRZUAT-UHFFFAOYSA-N 0.000 description 1
- 206010007269 Carcinogenicity Diseases 0.000 description 1
- 230000010757 Reduction Activity Effects 0.000 description 1
- 206010043275 Teratogenicity Diseases 0.000 description 1
- 238000000026 X-ray photoelectron spectrum Methods 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000007670 carcinogenicity Effects 0.000 description 1
- 231100000260 carcinogenicity Toxicity 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 238000006555 catalytic reaction Methods 0.000 description 1
- JOPOVCBBYLSVDA-UHFFFAOYSA-N chromium(6+) Chemical compound [Cr+6] JOPOVCBBYLSVDA-UHFFFAOYSA-N 0.000 description 1
- 238000010835 comparative analysis Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000009713 electroplating Methods 0.000 description 1
- 235000019441 ethanol Nutrition 0.000 description 1
- 125000001495 ethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 239000010842 industrial wastewater Substances 0.000 description 1
- 238000005272 metallurgy Methods 0.000 description 1
- 238000013508 migration Methods 0.000 description 1
- 230000005012 migration Effects 0.000 description 1
- 238000011056 performance test Methods 0.000 description 1
- 230000002085 persistent effect Effects 0.000 description 1
- 125000001997 phenyl group Chemical group [H]C1=C([H])C([H])=C(*)C([H])=C1[H] 0.000 description 1
- 230000008092 positive effect Effects 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 231100000211 teratogenicity Toxicity 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- YAPQBXQYLJRXSA-UHFFFAOYSA-N theobromine Chemical compound CN1C(=O)NC(=O)C2=C1N=CN2C YAPQBXQYLJRXSA-UHFFFAOYSA-N 0.000 description 1
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Abstract
The invention discloses a modified g-C3N4A photocatalyst and a preparation method thereof. Modified g-C of the invention3N4Having a surface of-NH2The functional groups such as NH, phenolic hydroxyl and the like have higher enrichment capacity on Cr (VI) in the water body, thereby improving the efficiency of the catalyst for reducing Cr (VI) in the water body by photocatalysis. The invention prepares the graphite phase g-C by the pyrolysis of melamine3N4Covalently grafting salicylaldehyde to g-C3N4Surface, finally obtaining modified g-C by reduction3N4. The preparation method has the advantages of easily available raw materials, low cost, mild reaction conditions and no pollution to the environment.
Description
Technical Field
The invention relates to the field of semiconductor photocatalysts, in particular to modified g-C3N4A photocatalyst and a preparation method thereof.
Background
With the development of socioeconomic, energy shortage and environmental pollution have become two great challenges facing today's human society. Especially nearly two and threeOver the decade, with the rapid expansion of economic globalization, mankind enjoys the effects of social development and the accompanying consequences. In the aspect of environment, a large amount of pollutants containing heavy metals enter water environment due to human activities, so that resource loss is caused, and meanwhile, the ecological balance and human health are greatly influenced. Hexavalent chromium (cr (vi)) is one of the most common heavy metal pollutants, widely exists in industrial wastewater of metallurgy, electroplating, tanning and the like, has strong carcinogenicity and teratogenicity, and has a persistent risk to the environment. The traditional Cr (VI) treatment method is to add a reducing agent into the polluted water body to reduce Cr (VI) into Cr (III), and then form Cr (OH) under the alkaline condition3The precipitate is removed, but a large amount of reducing agent is consumed and secondary pollution is possible. In recent years, the catalytic reduction of Cr (VI) in water by using a semiconductor photocatalysis technology has attracted much attention.
Graphite phase carbon nitride (g-C)3N4) As a non-metal semiconductor, the silicon-based non-metal semiconductor has the advantages of narrow forbidden band width, stable chemical property, strong compatibility and the like, so that the silicon-based non-metal semiconductor has great development potential in the field of catalysts. However, the graphite-phase carbon nitride photocatalyst has the defects of small specific surface area, low quantum efficiency and the like, so that the catalytic efficiency of the photocatalyst is low. The precondition for the occurrence of the photocatalytic reaction is that pollutants are adsorbed on the surface of the catalyst, so the enrichment capacity of the catalyst on the pollutants in the water body directly influences the whole photocatalytic reaction efficiency. The development of a carbon nitride catalyst with large specific surface area, strong adsorption capacity and high photocatalytic efficiency is urgently needed.
Disclosure of Invention
The invention aims to solve the problems of small specific surface area, poor adsorption capacity and low photocatalytic efficiency of a carbon nitride catalyst in the prior art, and provides modified g-C3N4The photocatalyst greatly enhances the enrichment capacity of the photocatalyst on pollutants by modifying the structure of the photocatalyst, so that the catalytic reduction efficiency of the photocatalyst is greatly improved.
In order to achieve the above purpose of the present invention, the technical scheme adopted by the present invention is as follows: modified g-C3N4A photocatalyst having a structure such asThe following formula (g-C)3N4-Sal) in a chemical structure,
in a second aspect of the present invention, there is provided the modified g-C as described above3N4The preparation method of the photocatalyst comprises the following steps:
a. calcining melamine at high temperature to obtain graphite phase (g-C)3N4)；
b. The (g-C) prepared in step a3N4) Grafting reaction with salicylaldehyde to obtain (g-C)3N4＝Sal)；
c. (g-C) obtained in step b3N4Sal) with sodium borohydride to give modified g-C3N4Photocatalyst (g-C)3N4-Sal). The specific reaction scheme is as follows.
In the step a, the high-temperature calcination temperature is 500-600 ℃, the calcination time is 1-6 hours, and preferably 4 hours. Preferably in a tube furnace.
Among them, the step b is preferably carried out in a solvent, and the solvent is absolute ethyl alcohol. Preferably, the (g-C)3N4) The mass ratio of the absolute ethyl alcohol to the absolute ethyl alcohol is (3-8): (100-180), wherein the volume ratio of the salicylaldehyde to the absolute ethyl alcohol is (5-15): (100-180). Preferably, the reaction temperature is 50-75 ℃, and the reaction time is 8-48 h.
As an example, step b comprises reacting (g-C) obtained in step a3N4) Adding the photocatalyst into the absolute ethyl alcohol solution, dropwise adding salicylaldehyde into the mixed solution, and heating and carrying out reflux reaction to obtain (g-C)3N4＝Sal)。
Wherein, in the step c, the reaction is preferably carried out in a solvent, and the solvent is absolute ethyl alcohol; preferably, said (g-C)3N4Sal) and anhydrous ethyl acetateThe mass ratio of the alcohol (3-8): (100-180), the mass ratio of sodium borohydride to absolute ethyl alcohol (0.5-3): (100-180). Preferably, the reaction temperature is 50-75 ℃, and the reaction time is 5-10 h.
Modified g-C of the invention3N4Principle of photocatalyst: the invention prepares the graphite phase g-C by pyrolyzing melamine at high temperature3N4By means of its surface-rich-NH2Salicylic aldehyde is used as a functional group molecule as an active modification site, g-C3N4surface-NH2Grafting reaction with aldehyde group-CHO in salicylaldehyde molecular structure to generate-N ═ C-covalent double bond, reducing-N ═ C-to-N-C-single bond through reduction reaction, and finally obtaining modified g-C3N4Photocatalyst (g-C)3N4- Sal)，(g-C3N4-NH-of the Sal) molecule2The NH-group and the phenolic hydroxyl group adsorb Cr (VI) ions in the water body through electrostatic attraction, coordination and hydrogen bond, thereby greatly improving the g-C3N4The Sal can enrich Cr (VI) in the water body, so that the catalytic reduction efficiency of Cr (VI) in the catalytic reaction is improved.
Compared with the prior art, the invention has the following positive effects:
(1) the invention makes full use of g-C3N4Surface rich-NH2The adsorption capacity of the catalyst to Cr (VI) in a water body is greatly improved by grafting the functionalized functional group, so that the activity of the catalyst in photocatalytic reduction is promoted;
(2) modified g-C of the invention3N4The photocatalyst can greatly improve the photocatalytic reduction capability of the catalyst on heavy metal ions (particularly Cr (VI) ions) in a water body, and has a good treatment effect on high-concentration heavy metal polluted water;
(3) modified g-C of the invention3N4The photocatalyst has the advantages of simple preparation method, easily obtained raw materials, low cost, mild reaction conditions, no environmental pollution and easy industrial production.
Drawings
FIG. 1 shows g-C prepared in example 3 of the present invention3N4Comparison graphs of infrared spectra before and after photocatalyst modification;
FIG. 2 shows g-C prepared in example 3 of the present invention3N4XPS characterization map before photocatalyst modification;
FIG. 3 shows g-C prepared in example 3 of the present invention3N4XPS characterization map after photocatalyst modification;
FIG. 4 shows g-C prepared in example 3 of the present invention3N4Adsorption kinetics graphs of Cr (VI) before and after photocatalyst modification;
FIG. 5 shows g-C prepared in example 3 of the present invention3N4And (3) a comparison graph of the adsorption-visible light catalytic reduction performance of Cr (VI) before and after the modification of the photocatalyst.
Detailed Description
The invention will be described in further detail with reference to the following figures and specific embodiments. The following examples are merely illustrative and explanatory of the present invention and should not be construed as limiting the scope of the invention. All the technologies realized based on the above-mentioned contents of the present invention are covered in the protection scope of the present invention.
< preparation examples >
(example 1)
50g of melamine is placed in a tube furnace and calcined for 4 hours at the high temperature of 500 ℃ to obtain g-C3N4A photocatalyst.
6g of the obtained g-C3N4Adding a photocatalyst into 150mL of absolute ethanol solution, dropwise adding 6mL of salicylaldehyde into the mixed solution, heating and refluxing for 8h, washing and drying a product after reaction, and recording the obtained product as (g-C)3N4＝Sal)。
4g of the (g-C) obtained3N4Sal) is added into 150mL absolute ethyl alcohol solution, 1g sodium borohydride is added, heating reflux reaction is carried out for 5h, and the product after reaction is washed and dried to obtain modified g-C3N4Is marked as g-C3N4-Sal。
(example 2)
By the operation of reference example 1, g-C was obtained3N4A photocatalyst. 6g of the resulting g-C3N4Adding a photocatalyst into 150mL of absolute ethanol solution, dropwise adding 8mL of salicylaldehyde into the mixed solution, heating and refluxing for 10h, washing and drying a product after reaction, and recording the obtained product as (g-C)3N4Sal). 4g of (g-C) obtained above3N4Sal) is added into 150mL absolute ethyl alcohol solution, 1.5g sodium borohydride is added, heating reflux reaction is carried out for 6h, and the product after reaction is washed and dried to obtain modified g-C3N4Is denoted by (g-C)3N4-Sal)。
(example 3)
By the operation of reference example 1, g-C was obtained3N4A photocatalyst. 6g of the resulting g-C3N4Adding a photocatalyst into 150mL of absolute ethanol solution, dropwise adding 10mL of salicylaldehyde into the mixed solution, heating and refluxing for reaction for 15h, washing and drying a product after the reaction, and recording the obtained product as (g-C)3N4Sal). 4g of (g-C) prepared3N4Sal) is added into 150mL absolute ethyl alcohol solution, then 2g sodium borohydride is added, heating reflux reaction is carried out for 8h, and the product after reaction is washed and dried to obtain modified g-C3N4Is denoted by (g-C)3N4-Sal)。
(example 4)
By the operation of reference example 1, g-C was obtained3N4A photocatalyst. 6g of the resulting g-C3N4Adding a photocatalyst into 150mL of absolute ethanol solution, dropwise adding 12mL of salicylaldehyde into the mixed solution, heating and refluxing for reaction for 24 hours, washing and drying a product after the reaction, and recording the obtained product as (g-C)3N4Sal). 4g of (g-C) prepared3N4Sal) is added into 150mL absolute ethyl alcohol solution, then 2.5g sodium borohydride is added, heating reflux reaction is carried out for 10h, and the product after reaction is washed and dried to obtain modified g-C3N4Is denoted by (g-C)3N4-Sal)。
< Performance test >
(example 5)
g-C before modification3N4And after modification g-C3N4-infrared spectroscopic characterization of Sal
As shown in FIG. 1, g-C prepared for example 33N4Sal and g-C3N4The modified g-C is found by comparative analysis3N4-the Sal IR spectrum shows a series of new peaks: at 2870cm-1The peak of (A) belongs to-CH2Stretching vibration of the keys, 1120 cm-1The peak at (A) is assigned to the absorption peak of phenolic hydroxyl group, 740cm-1The peak at (B) is ascribed to the characteristic absorption peak of benzene ring, and furthermore, is located at 3150-3300cm-1NH of (C)2The tensile vibration strength was reduced, indicating that salicylaldehyde was successfully modified to g-C3N4A surface.
(example 6)
g-C before modification3N4And modified g-C3N4Characterization analysis of Sal XPS N1s
FIGS. 2 and 3 are g-C prepared in example 3, respectively3N4And g-C3N4-Sal N1s high resolution XPS spectra. As shown in the figure, g-C3N4Shows three fitting peaks corresponding to g-C3N4Triazine structure N ═ C-N (398.4eV), N- (C)3(399.3eV) and C-N-H2(400.9 eV). And g-C3N4In comparison with the energy spectrum of g-C3N4C-N-H at 400.9eV in the Sal-fitted peak2The peak is reduced, and a new peak appears at 398.7eV, which can be assigned as H-N- (C)2Bond, indicates g-C3N4surface-NH2A covalent grafting reaction with salicylaldehyde occurred, which is consistent with the infrared characterization results.
(example 7)
The g-C prepared in examples 1 to 4 were measured separately3N4-adsorption of cr (vi) ions in solution by Sal-capacity for visible photocatalytic reduction removal.
The test method is as follows: taking 450mL of solution with Cr (VI) concentration of 60mg/L, and adjusting the pH value of the solution to2.5, 0.45g of g-C prepared in examples 1 to 4 were added3N4Oscillating Sal catalyst at constant temperature for 1h, starting visible light source to irradiate for 4h after adsorption reaches balance, performing photocatalytic reduction experiment, taking out solution after experiment is finished, centrifuging with high-speed centrifuge, measuring Cr (VI) ion concentration in supernatant, and collecting the supernatant according to the following formula
Obtaining the removal rate, wherein (1) formula: r is the removal rate (%), C0The initial concentration (mg/L) of Cr (VI) in the solution, CeThe concentration (mg/L) of Cr (VI) in the solution after the adsorption-photocatalytic reduction reaction. The results are shown in Table 1.
TABLE 1 modified g-C obtained in examples 1 to 43N4Removal rate of Cr (VI) by photocatalyst
As can be seen from the above table, modified g-C prepared according to the invention3N4The photocatalyst has high Cr (VI) removal rate and good adsorptivity.
Example 8 adsorption kinetics experiment
200mL of a 30mg/L Cr (VI) solution were taken in two portions in conical flasks having respective stoppers, the pH of the solution was adjusted to 2.5, and 0.2g of g-C prepared in example 3 was added3N4And (g-C)3N4Sal) catalyst, shaking at constant temperature (25 ℃) in a constant temperature shaker, taking the solution out at intervals and centrifuging it in a high-speed centrifuge, determining the concentration of Cr (VI) in the supernatant, according to the following formula
Determining the amount of adsorption QtAnd a graph of the adsorption amount versus time was plotted, and the result is shown in fig. 4.
Wherein, onIn the formula: qtAs adsorbed amount (mg/g), C0The concentration (mg/L) of Cr (VI) in the solution before adsorption, CeAs the concentration in the solution after adsorption (mg/L), V is the solution volume (L) and W is the catalyst mass (g). As can be seen from FIG. 4, (g-C) after modification3N4The maximum adsorption capacity of Sal) to Cr (VI) can reach 25.3mg/g, which greatly exceeds g-C before modification3N4The adsorption amount of (1) was 12.5 mg/g.
Example 9 adsorption-photocatalytic reduction removal experiment
450mL of a solution containing 60mg/L of Cr (VI) was divided into two portions, the pH of the solution was adjusted to 2.5, and 0.45g of (g-C) prepared in example 3 was added3N4-Sal) and g-C3N4And oscillating the catalyst at constant temperature for 1h, starting a visible light source to irradiate for 4h after the adsorption reaches balance, and carrying out a photocatalytic reduction experiment. The results are shown in FIG. 5, in which the solutions were taken out at regular intervals from the start of the experiment to the end of the experiment, centrifuged by a high-speed centrifuge, and then the concentration of Cr (VI) ions in the supernatant was measured to determine the removal rate according to the formula (1).
As can be seen from FIG. 5, (g-C)3N4-Sal) and g-C3N4The removal rates for Cr (VI) were 94.7% and 61.5%, respectively, indicating that (g-C) was modified3N4The adsorption-visible light catalytic reduction activity of Sal) on Cr (VI) is obviously improved, because g-C is increased by grafting salicylaldehyde molecules3N4Number of surface-functional groups, (g-C)3N4the-NH 2, -NH-and phenolic hydroxyl groups on the surface of the-Sal) enrich Cr (VI) ions in the water body through electrostatic attraction, coordination and hydrogen bonding, so that the migration of Cr (VI) in the water phase to the surface of the catalyst can be greatly accelerated, and the photocatalytic reaction can be further promoted.
It should be understood that the above-described specific embodiments are merely illustrative of the invention and are not to be construed as limiting the invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Obvious variations or modifications which are within the spirit of the invention are possible within the scope of the invention.
Claims (7)
1. Modified g-C3N4A photocatalyst having the chemical structure of:
2. modified g-C according to claim 13N4The preparation method of the photocatalyst is characterized by adopting the following route to prepare:
the method specifically comprises the following steps of,
a. calcining melamine at high temperature to obtain graphite phase g-C3N4；
b. g-C prepared in step a3N4Grafting reaction with salicylaldehyde to obtain g-C3N4＝Sal；
c. g-C prepared in step b3N4Reduction of Sal with sodium borohydride to give modified g-C3N4Photocatalyst g-C3N4-Sal。
3. The preparation method of claim 2, wherein in the step a, the high-temperature calcination temperature is 500-600 ℃, and the calcination time is 1-6 h.
4. The method according to claim 2, wherein the solvent used in the reaction in step b is absolute ethanol; the g to C3N4The mass ratio of the absolute ethyl alcohol to the absolute ethyl alcohol is (3-8): (100-180), wherein the volume ratio of the salicylaldehyde to the absolute ethyl alcohol is (5-15): (100-180).
5. The preparation method according to claim 2, wherein the reaction temperature in the step b is 50-75 ℃ and the reaction time is 8-48 h.
6. The method according to claim 2, wherein in step c, the solvent used in the reaction is absolute ethanol; the g to C3N4The mass ratio of Sal to absolute ethyl alcohol (3-8): (100-180), the mass ratio of sodium borohydride to absolute ethyl alcohol (0.5-3): (100-180).
7. The preparation method according to claim 2, wherein in the step c, the reaction temperature is 50-75 ℃ and the reaction time is 5-10 h.
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| CN108067281B (en) * | 2017-11-24 | 2020-06-16 | 辽宁大学 | Porous g-C3N4Photocatalyst and preparation method and application thereof |
| CN108043440B (en) * | 2017-11-28 | 2020-06-16 | 辽宁大学 | Highly reactive porous g-C3N4Photocatalyst and preparation method and application thereof |
| CN110142055B (en) * | 2018-02-11 | 2022-04-12 | 天津理工大学 | Microwave irradiation method for enhancing photocatalytic performance of graphite-phase carbon nitride |
| CN110433844B (en) * | 2019-08-08 | 2022-04-08 | 盐城工学院 | Be used for high-efficient processing to contain Cr6+(B, O) Co-doping of waste Water with g-C3N4Method for preparing photocatalyst |
| CN110548534A (en) * | 2019-09-18 | 2019-12-10 | 常州大学 | preparation method of amino-modified flaky carbon nitride photocatalytic material |
| CN112958139A (en) * | 2021-03-08 | 2021-06-15 | 西北师范大学 | Preparation of CNK-OH/ferroferric oxide composite material and application of CNK-OH/ferroferric oxide composite material in photocatalytic degradation of tetracycline hydrochloride |
| CN116328719A (en) * | 2021-12-22 | 2023-06-27 | 湖南中烟工业有限责任公司 | Phenolic hydroxyl modified activated carbon and preparation method and application thereof |
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