CN115254169A - Nonmetal catalyst and preparation method and application thereof - Google Patents

Nonmetal catalyst and preparation method and application thereof Download PDF

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CN115254169A
CN115254169A CN202210973675.9A CN202210973675A CN115254169A CN 115254169 A CN115254169 A CN 115254169A CN 202210973675 A CN202210973675 A CN 202210973675A CN 115254169 A CN115254169 A CN 115254169A
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pcn
iii
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CN115254169B (en
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李春梅
程莎莎
方雨海
董红军
陈宇翔
苏楠
张平凡
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Jiangsu University
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
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    • B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
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    • C01B3/00—Hydrogen; Gaseous mixtures containing hydrogen; Separation of hydrogen from mixtures containing it; Purification of hydrogen
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    • C01B3/04—Production of hydrogen or of gaseous mixtures containing a substantial proportion of hydrogen by decomposition of inorganic compounds, e.g. ammonia
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    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B2203/00—Integrated processes for the production of hydrogen or synthesis gas
    • C01B2203/10—Catalysts for performing the hydrogen forming reactions
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    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/30—Hydrogen technology
    • Y02E60/36—Hydrogen production from non-carbon containing sources, e.g. by water electrolysis

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Abstract

The invention provides a non-metal catalyst and a preparation method and application thereof, belonging to the technical field of nano material synthesis and catalyst preparation; in the invention, firstly, potassium thiocyanate and potassium bisulfate are utilized to prepare a non-metal polymer SCN, and then the obtained SCN and PCN are calcined to obtain a non-metal catalyst; the catalyst is a composite catalyst with a heterojunction structure, which is constructed by nonmetal polymers SCN and PCN, and the composite catalyst has a structure that one-dimensional nanobelts grow on two-dimensional nanosheets; in the composite catalyst, PCN is a two-dimensional nanosheet structure, SCN is a nonmetal polymer with a relatively smooth surface and an irregular shape, which is prepared by reacting potassium thiocyanate and potassium bisulfate in an oil bath, and the load capacity of the nonmetal polymer is 1-7 wt% of the PCN; the nonmetal catalyst with the special structure has good application in hydrogen production by photocracking water.

Description

Nonmetal catalyst and preparation method and application thereof
Technical Field
The invention belongs to the technical field of nano material synthesis and catalyst preparation, and particularly relates to a non-metal catalyst and a preparation method and application thereof.
Background
Due to the rapid growth of the population and the rapid development of the modern industry, how to solve the problem of energy shortage has become a great challenge. The over-development of fossil energy has led to gradual depletion of energy, and its heavy use has led to a large amount of carbon emissions, which in turn has led to an increasing greenhouse effect. Hydrogen energy is used as clean energy with zero pollution, high heat value and rich raw materials, and becomes the central importance of energy development all over the world. The photocatalytic water splitting technology utilizes renewable water resources and solar energy, so that the photocatalytic water splitting technology is considered to be a green and environment-friendly hydrogen production method with great application prospect.
In order to meet the requirement of high-efficiency photocatalytic water decomposition, the research and development of photocatalytic materials are urgently needed. Graphite Phase Carbon Nitride (PCN) is considered to be a highly efficient photocatalyst, which has the advantages of appropriate band structure, easy synthesis, strong visible light absorption capability, low cost, good stability and the like, and is a multifunctional photocatalyst. However, PCN still faces problems of small specific surface area, fast carrier recombination, and the like, and thus modification of PCN is required to enhance its photocatalytic activity.
Disclosure of Invention
Aiming at some defects in the prior art, the invention provides a nonmetal catalyst and a preparation method and application thereof. In the invention, firstly, potassium thiocyanate and potassium bisulfate are utilized to prepare a non-metal polymer SCN, and then the obtained SCN and PCN are calcined to obtain a non-metal catalyst; the nonmetal catalyst has a special structure that the one-dimensional nanobelt grows on the two-dimensional nanosheets, and the introduction of the one-dimensional nanobelt does not change the original structural characteristics of the PCN; the non-metal catalyst has good application in hydrogen production by photocracking water.
Firstly, providing a non-metal catalyst, wherein the catalyst is a composite catalyst with a heterojunction structure and constructed by non-metal polymers SCN and PCN, and the composite catalyst is in a structure that one-dimensional nanobelts grow on two-dimensional nanosheets; in the composite catalyst, PCN is a two-dimensional nanosheet structure, SCN is a non-metallic polymer which is prepared by reacting potassium thiocyanate and potassium bisulfate in an oil bath and has a relatively smooth surface and an irregular shape, and the load capacity of the non-metallic polymer is 1-7 wt% of the PCN.
The invention also provides a preparation method of the nonmetal catalyst, which comprises the following steps:
(1) Preparation of non-metallic polymer SCN:
potassium sulfocyanide (KSCN) and potassium bisulfate (K) 2 S 2 O 8 ) Adding deionized water, stirring and mixing until the mixture is in an orange slurry state, drying in an oil bath to obtain a SCN crude sample, washing, centrifuging and drying to obtain a nonmetal polymer SCN;
(2) Preparing a nonmetal composite photocatalyst:
fully grinding the nonmetal polymer SCN and urea, calcining at 500-550 ℃, and obtaining the nonmetal composite photocatalyst after calcining, wherein CN-X% of SCN (X% is the mass percentage of SCN in PCN generated by calcining urea).
Further, in the step (1), the potassium thiocyanate (KSCN) and potassium bisulfate (K) are used 2 S 2 O 8 ) In a molar ratio of 4 to 1:1.
further, in the step (1), the stirring and mixing conditions are as follows: the stirring temperature is 30-40 ℃, the stirring speed is 600-800 rpm, and the stirring time is 16-20 h.
Further, in the step (1), drying is carried out for 4-5 hours at 70-80 ℃ under the oil bath drying condition.
Further, in the step (2), the mass ratio of SCN to PCN generated after urea calcination is 1-7: 100.
further, in the step (2), the grinding time is 30-60 min.
Further, in the step (2), the temperature rise rate of the calcination is 2.5-5 ℃/min, and the calcination time is 3-4 h.
The invention also provides application of the non-metal composite photocatalyst in hydrogen production by photocracking water.
Compared with the prior art, the invention has the beneficial effects that:
according to the invention, a high-efficiency and stable non-metal composite photocatalytic system is formed by using the PCN nanosheet with the two-dimensional morphology through the steps of stirring, drying, calcining and the like. The composite catalyst with the heterojunction structure is constructed, and the construction of the heterojunction can form an internal electrostatic field and promote the transfer and separation of photon-generated carriers. In addition, the catalyst prepared by the invention has a special structure that the one-dimensional nanobelt grows on the two-dimensional nanosheets, the original structural characteristics of PCN are not changed by introducing the one-dimensional nanobelt, and by utilizing the one-dimensional and two-dimensional space difference, not only can richer active sites be generated and exposed, but also a higher specific surface area can be provided, and the transmission length of a current carrier can be shortened, so that the photocatalytic activity is effectively improved.
The amount of raw materials and other reaction parameters in the invention affect the structure and photocatalytic activity of the catalyst. In the present invention, by precisely controlling KSCN and K 2 S 2 O 8 The dosage of the non-metal polymer SCN, the mixing time of the mixture, the drying temperature and the drying time and other factors are regulated and controlled, the non-metal polymer SCN with different molar ratios is prepared, and the SCN with the optimal molar ratio is screened out by utilizing a photocracking water hydrogen production experiment, wherein the molar ratio is 2:1, the SCN-III has the highest polymerization degree and the best hydrogen production performance. The invention also constructs a non-metal composite photocatalyst CN-X% SCN-III system by utilizing the optimal reaction parameters, and finally determines that the dosage of SCN-III is 1%, 3%, 5% and 7% of the PCN generated by calcining urea in sequence by continuously adjusting the dosage of SCN-III and verifying the photocatalytic performance by utilizing a water hydrogen production test by photocracking, wherein the photocatalytic hydrogen production performance with the dosage of SCN-III of 3% is optimal. The rate of hydrogen production by photocleavage of water by CN-3% SCN-III composite photocatalyst reached to a maximum of 2125.8umol h - 1 g -1 。
In the preparation process, the composite process is safe and simple to operate, and a high-pressure reaction step is avoided; the required equipment is a common device in a laboratory, the experimental conditions are easily met, the cost is low, and the obtained catalyst has high hydrogen production activity and is beneficial to practical production and application.
Drawings
FIG. 1 is an XRD spectrum of SCN-III, PCN and CN-3% SCN-III.
FIG. 2 is a TEM image of SCN-III (a) and PCN (b).
FIG. 3 is a TEM image of CN-3% SCN-III (a) and CN-3% SCN-III (b) after Pt light deposition.
FIG. 4 shows PCN and CN-3% of SCN-III N 2 Adsorption-desorption isotherms.
FIG. 5 is a graph of the performance of hydrogen production by photocleavage of water with PCN and CN-X% SCN-III.
FIG. 6 is a graph of hydrogen production performance by photosplitting water of the non-metal composite photocatalyst obtained by loading 3wt% of SCN prepared at different molar ratios.
FIG. 7 is XRD spectra of CN-3%.
FIG. 8 shows the linear sweep voltammogram (a) and impedance spectrum (b) of PCN and CN-3% SCN-III.
FIG. 9 is a photocurrent curve of PCN and CN-3% SCN-III.
Detailed Description
The invention will be further described with reference to the following figures and specific examples, but the scope of the invention is not limited thereto.
Example 1: CN-3% SCN-III photocatalyst preparation
(1) Preparation of non-metallic polymer SCN-iii with molar ratio 2:1:
weighing 4.9g of potassium thiocyanate and 6.8g of potassium bisulfate, placing the potassium thiocyanate and the potassium bisulfate in a beaker, adding 60mL of deionized water, stirring at 35 ℃ for 18 hours at the stirring speed of 700rpm, and drying the mixture in an oil bath at 70 ℃ for 4 hours when the mixture is in a thick orange slurry state to obtain a crude SCN-III sample.
To remove impurities that failed polymerization, the crude sample was first soaked with 120mL of absolute ethanol, stirred for 2 hours and then washed 3 times with water at 8000rpm for a period of 4 minutes, soaked with 120mL of deionized water, stirred for 2 hours and then washed 3 times with water at 8000rpm for a period of 4 minutes. Then vacuum drying is carried out for 10 hours at 60 ℃, and finally a nonmetallic polymer SCN-III sample with the molar ratio of 2:1 is obtained.
(2) CN-3% SCN-III photocatalyst preparation:
weighing 24mg of SCN-III and 20g of urea, placing the SCN-III and the urea into a mortar, grinding the mixture for 45 minutes, placing the mixture into a muffle furnace for calcination, wherein the calcination temperature is 550 ℃, the heating rate is 2.5 ℃/min, the calcination time is 4 hours, and the solid powder obtained after calcination is the non-metal composite photocatalyst which is calculated as CN-3 percent SCN-III.
FIG. 1 is an XRD spectrum of SCN-III, PCN and CN-3% SCN-III. As can be seen in FIG. 1, the XRD pattern of the CN-3% SCN-III sample was substantially unchanged from that of pure PCN, indicating that the structure of PCN was hardly changed by the heterojunction.
FIG. 2 is a TEM image of SCN-III (a) and PCN (b). As can be seen in fig. 2, SCN-iii exhibits an irregular shape, with a relatively smooth surface; PCN exhibits the typical two-dimensional nanosheet morphology.
FIG. 3 is a TEM image of CN-3%SCN-III (a) and CN-3%. As can be seen from FIG. 3a, SCN-III and PCN successfully constructed a heterojunction, CN-3% SCN-III composite photocatalyst having a one-dimensional nanoribbon growth on a two-dimensional nanosheet; as can be seen in fig. 3b, the Pt photo-deposition sites are on the nanobelts, indicating that the photo-splitting water hydrogen production active sites are located on the one-dimensional nanobelts.
FIG. 4 shows PCN and CN-3% of SCN-III N 2 Adsorption-desorption isotherms. As can be seen in FIG. 4, the isothermal hysteresis of the PCN and CN-3% SCN-III samples occurred between 0.4 and 1.0, indicating that both have mesostructures present therein and that CN-3% SCN-III has a larger specific surface area.
Example 2: CN-1% SCN-III photocatalyst preparation
Step (1) is the same as in example 1.
(2) CN-1% SCN-III photocatalyst preparation:
weighing 8mg of SCN-III and 20g of urea, placing the SCN-III and the urea into a mortar, grinding for 45 minutes, placing the ground SCN-III and the urea into a muffle furnace for calcination, wherein the calcination temperature is 500 ℃, the heating rate is 2.5 ℃/min, and the calcination time is 3 hours. The solid powder obtained after calcination is the nonmetal composite photocatalyst, and is marked as CN-1 percent SCN-III.
Example 3: CN-5% SCN-III photocatalyst preparation
Step (1) is the same as in example 1.
(2) CN-5% preparation of SCN-III photocatalyst:
weighing 40mg of SCN-III and 20g of urea, placing the SCN-III and the urea in a mortar, grinding for 45 minutes, placing the ground SCN-III and the urea in a muffle furnace for calcination, wherein the calcination temperature is 550 ℃, the temperature rise rate is 2.5 ℃/min, and the calcination time is 4 hours. The solid powder obtained after calcination is the nonmetal composite photocatalyst, which is recorded as CN-5 percent SCN-III.
Example 4: CN-7% SCN-III photocatalyst preparation
Step (1) is the same as in example 1.
(2) CN-7% preparation of SCN-III photocatalyst:
weighing 56mg of SCN-III and 20g of urea, placing the SCN-III and the urea in a mortar, grinding for 45 minutes, placing the ground SCN-III and the urea in a muffle furnace for calcination, wherein the calcination temperature is 550 ℃, the temperature rise rate is 2.5 ℃/min, and the calcination time is 4 hours. The solid powder obtained after calcination is the nonmetal composite photocatalyst, which is recorded as CN-7 percent SCN-III.
Example 5: application of non-metal composite photocatalyst CN-X% SCN-III in hydrogen production by photocracking water
In this example, the performance of the non-metal composite photocatalyst prepared in examples 1 to 4, i.e., CN-1% SCN-III, CN-3% SCN-III, CN-5% SCN-III and CN-7% SCN-III, for catalyzing the photocleavage of water to produce hydrogen, was examined using pure PCN as a control group.
Wherein, the preparation steps of the pure PCN are as follows:
20g of urea is weighed and placed in a mortar, ground for 45 minutes and then placed in a muffle furnace for calcination. The calcining temperature is 550 ℃, the heating rate is 2.5 ℃/min, and the calcining time is 4 hours. And calcining to obtain solid powder, namely the PCN.
The experimental process for preparing hydrogen by photo-splitting water comprises the following steps:
an experiment of preparing hydrogen by photo-splitting water is carried out under an all-glass automatic on-line trace gas analysis system, 50mg of photocatalyst is uniformly dispersed in 100mL of Triethanolamine (TEOA) aqueous solution with the concentration of 10vol%, and 1.5mL of H is added 2 PtCl 6 ·H 2 O solution (1 mg/mL Pt). In the reaction process, circulating water of 5 ℃ is used for maintaining the temperature of the reaction system, a vacuum pump evacuates air in the reactor, then a 300W xenon lamp provided with a 420nm cut-off filter is used as a visible light source, and an online gas chromatography system is used for measuring the generated H 2 The amount of (c).
FIG. 5 is a diagram showing the performance of hydrogen production by photosplitting water of PCN and CN-X% SCN-III, and it can be seen from the diagram that the hydrogen production rate by photosplitting water of CN-X% SCN-III composite photocatalyst can reach 2125.8 mu mol h -1 g -1 And the high performance of hydrogen production by photocracking water is reflected. In addition, it can be seen that the hydrogen production rate of the best composite is 4 times that of pure PCN (the hydrogen production rate of PCN is 530.8 μmol h -1 g -1 ). With the increase of the SCN load, the hydrogen production performance of the composite photocatalyst is gradually enhanced, when the SCN load reaches 3%, the hydrogen production rate is the highest, and then the hydrogen production rate is reduced with the increase of the SCN load; this suggests that excess SCN may adversely impair the hydrogen production performance of the photocatalyst.
FIG. 8 shows the linear sweep voltammogram (a) and impedance spectrum (b) of PCN and CN-3% SCN-III. As shown in FIG. 8a, the overpotential of CN-3% SCN-III is less than that of PCN at the same current density, indicating that the overpotential is significantly reduced after the heterojunction is successfully constructed, and the hydrogen production activity by photosplitting water is fundamentally improved. FIG. 8b is an impedance spectrum of PCN and CN-3% SCN-III, with the diameter of CN-3% SCN-III impedance being much smaller than that of pure PCN, indicating improved conductivity of the catalyst after heterojunction construction and accelerated charge transfer process, thereby improving the performance of photosplitting water to produce hydrogen.
FIG. 9 is a photocurrent curve of PCN and CN-3% SCN-III. As shown in FIG. 8, under visible light irradiation, PCN and CN-3% were able to detect a stable and rapid photocurrent response on SCN-III, and CN-3% SCN-III showed significantly higher photocurrent density, indicating accelerated transfer and separation of photogenerated carriers after successful heterojunction construction.
In order to verify the stability of the composite photocatalyst, in this example, a cyclic hydrogen production experiment was performed on CN-3% SCN-III composite photocatalyst for 5 consecutive times, for a total of 20 hours, and a sample obtained by recycling CN-3% SCN-III composite photocatalyst was collected and subjected to XRD diffraction, and whether the sample was stable or not was determined by comparing XRD spectra of CN-3% SCN-III before and after the recycling, and the comparison result is shown in FIG. 7.
FIG. 7 is XRD spectra of CN-3% SCN-III before and after cycling reaction. As can be seen from FIG. 7, the XRD spectrum of the used sample is very consistent with that of the initial sample, which shows that the CN-X% SCN-III composite photocatalyst has very good stability.
Comparative example 1: CN-3% preparation of KSCN
24mg of KSCN and 20g of urea were weighed into a mortar, ground for 45 minutes and then placed in a muffle furnace for calcination. The calcination temperature was 550 deg.C, the temperature rise rate was 2.5 deg.C/min, the calcination time was 4 hours, and the solid powder obtained after calcination was CN-3% KSCN.
Comparative example 2: CN-3% SCN-II preparation
(1) Preparation of non-metallic polymer SCN-II with molar ratio 4:1:
6.9g of potassium thiocyanate and 4.8g of potassium sulfate were weighed into a beaker, 60mL of deionized water was added and stirred at 35 ℃ for 18 hours with the stirring rate set at 700rpm. When the mixture appeared to be a thick orange slurry, it was dried in an oil bath at 70 ℃ for 4 hours to give a crude SCN-II sample.
In order to remove the impurities which are not successfully polymerized, the crude sample is firstly soaked in 120mL of absolute ethyl alcohol, stirred for 2 hours and then centrifugally washed by water for 3 times, the rotating speed is 8000rpm, the duration is set to be 4 minutes, then the sample is soaked in 120mL of deionized water, stirred for 2 hours and then centrifugally washed by water for 3 times, the rotating speed is 8000rpm, the duration is set to be 4 minutes, then vacuum drying is carried out for 10 hours at the temperature of 60 ℃, and finally the nonmetal polymer SCN-II sample with the molar ratio of 4:1 is obtained.
(2) CN-3% SCN-II:
24mg of SCN-II and 20g of urea were weighed into a mortar, ground for 45 minutes and then calcined in a muffle furnace. The calcination temperature was 550 deg.C, the temperature rise rate was 2.5 deg.C/min, the calcination time was 4 hours, and the solid powder obtained after calcination was CN-3% SCN-II.
Comparative example 3: CN-3% preparation of SCN-IV
(1) Preparation of non-metallic polymer SCN-IV with molar ratio 1:1:
3.0g of potassium thiocyanate and 8.7g of potassium sulfate were weighed into a beaker, 60mL of deionized water was added and stirred at 35 ℃ for 18 hours with the stirring rate set at 700rpm. When the mixture appeared to be a thick orange slurry, it was dried in an oil bath at 70 ℃ for 4 hours to give a crude SCN-IV sample.
In order to remove impurities which are not successfully polymerized, the crude sample is firstly soaked in 120mL of absolute ethyl alcohol, stirred for 2 hours and then centrifugally washed by water for 3 times, the rotating speed is 8000rpm, the duration is set to be 4 minutes, then 120mL of deionized water is used for soaking the sample, stirred for 2 hours and then centrifugally washed by water for 3 times, the rotating speed is 8000rpm, the duration is set to be 4 minutes, then vacuum drying is carried out for 10 hours at the temperature of 60 ℃, and finally the nonmetal polymer SCN-IV sample with the molar ratio of 1:1 is obtained.
(2) CN-3% preparation of SCN-IV:
weighing 24mg of SCN-IV and 20g of urea, placing the SCN-IV and the urea into a mortar, grinding the SCN-IV and the urea for 45 minutes, placing the ground SCN-IV and the urea into a muffle furnace for calcination, wherein the calcination temperature is 550 ℃, the temperature rise rate is 2.5 ℃/min, the calcination time is 4 hours, and the solid powder obtained after calcination is CN-3 percent of SCN-IV.
Comparative example 4: CN-3%K 2 S 2 O 8 Preparation of
Weighing 24mg of K 2 S 2 O 8 And 20g of urea were put in a mortar, ground for 45 minutes and then placed in a muffle furnace for calcination. The calcining temperature is 550 ℃, the heating rate is 2.5 ℃/min, the calcining time is 4 hours, and the solid powder obtained after calcining is CN-3%K 2 S 2 O 8 。
In the comparative example, the performance of the non-metal polymer SCN prepared from potassium thiocyanate and potassium bisulfate with different molar ratios on hydrogen production by water photo-cracking of the finally prepared non-metal composite photocatalyst is examined by taking the average hydrogen production rate as an index. FIG. 6 is a graph showing the performance of hydrogen production by photosplitting water of the non-metal polymer SCN prepared from potassium thiocyanate and potassium bisulfate in different molar ratios to the finally prepared non-metal composite photocatalyst, and it can be seen from the graph that CN-3% of SCN-III in all the 3% SCN composite materials in different molar ratios is the best performance, so that SCN-III can be determined as the best polymer.
The examples are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any obvious modifications, substitutions or variations can be made by those skilled in the art without departing from the spirit of the present invention.

Claims (10)

1. The preparation method of the nonmetal catalyst is characterized by comprising the following steps of:
(1) Preparation of non-metallic polymer SCN:
potassium sulfocyanide (KSCN) and potassium bisulfate (K) 2 S 2 O 8 ) Adding deionized water, stirring and mixing until the mixture is in an orange slurry state, drying in an oil bath to obtain a crude SCN sample, washing, centrifuging and drying to obtain a nonmetal polymer SCN;
(2) Preparing a non-metal composite photocatalyst:
fully grinding the nonmetal polymer SCN and urea, calcining at 500-550 ℃, and obtaining the nonmetal composite photocatalyst after the calcination is finished.
2. The method for preparing the non-metallic catalyst according to claim 1, wherein in the step (1), the potassium thiocyanate (KSCN) and the potassium hydrogen sulfate (K) are 2 S 2 O 8 ) In a molar ratio of 4 to 1:1.
3. the method for preparing a non-metallic catalyst according to claim 1, wherein in the step (1), the conditions for stirring and mixing are as follows: the stirring temperature is 30-40 ℃, and the stirring time is 16-20 h.
4. The method for preparing a non-metallic catalyst according to claim 3, wherein the stirring rate is 600 to 800rpm.
5. The method for preparing a non-metallic catalyst according to claim 1, wherein the drying of the oil bath in the step (1) is performed under a condition of drying at 70 to 80 ℃ for 4 to 5 hours.
6. The method for preparing the non-metallic catalyst according to claim 1, wherein in the step (2), the mass ratio of the SCN to the PCN generated after the urea calcination is 1 to 7:100.
7. the method for preparing a non-metallic catalyst according to claim 1, wherein the grinding time in the step (2) is 30 to 60min.
8. The method for preparing a non-metallic catalyst according to claim 1, wherein in the step (2), the temperature rise rate of the calcination is 2.5-5 ℃/min, and the calcination time is 3-4 h.
9. The non-metallic catalyst prepared by the method of any one of claims 1 to 8, wherein the catalyst has a heterojunction structure, and in the catalyst, PCN is a two-dimensional nanosheet structure, and SCN is an irregularly-shaped non-metallic polymer with a relatively smooth surface, and the loading amount of the polymer is 1 to 7wt% of the PCN.
10. The use of the non-metal composite photocatalyst of claim 9 in photocracking water to produce hydrogen.
CN202210973675.9A 2022-08-15 2022-08-15 Nonmetal catalyst and preparation method and application thereof Active CN115254169B (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116161616A (en) * 2022-12-30 2023-05-26 合肥工业大学 Method for catalyzing sodium borohydride to quickly produce hydrogen at low temperature by nonmetal catalyst

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CN110961133A (en) * 2019-11-29 2020-04-07 江苏大学 Nonmetal BCN/g-C3N4Van der Waals heterojunction photocatalyst and preparation method and application thereof
CN112973751A (en) * 2021-02-05 2021-06-18 江苏大学 Ru monoatomic and g-C3N4Composite photocatalyst and preparation method and application thereof
CN114210328A (en) * 2021-12-29 2022-03-22 江苏大学 Rh monoatomic-modified PCN photocatalyst and preparation method and application thereof

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110961133A (en) * 2019-11-29 2020-04-07 江苏大学 Nonmetal BCN/g-C3N4Van der Waals heterojunction photocatalyst and preparation method and application thereof
CN112973751A (en) * 2021-02-05 2021-06-18 江苏大学 Ru monoatomic and g-C3N4Composite photocatalyst and preparation method and application thereof
CN114210328A (en) * 2021-12-29 2022-03-22 江苏大学 Rh monoatomic-modified PCN photocatalyst and preparation method and application thereof

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN116161616A (en) * 2022-12-30 2023-05-26 合肥工业大学 Method for catalyzing sodium borohydride to quickly produce hydrogen at low temperature by nonmetal catalyst
CN116161616B (en) * 2022-12-30 2024-04-19 合肥工业大学 Method for catalyzing sodium borohydride to quickly produce hydrogen at low temperature by nonmetal catalyst

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