Charged ligand post-modified photocatalyst, preparation method therefor and use thereof

Abstract

Provided are a charged ligand post-modified photocatalyst, a preparation method therefor, and a use thereof, relating to the field of photocatalysis. A zirconium salt and 1,3,5-tris(4-carboxyphenyl)benzene are dissolved in N,N-dimethylformamide, and then formic acid is added to obtain Zr-BTB; Zr-BTB and a potassium chloroplatinate solution are added to ethanol to implement a reaction to obtain Zr-BTB@Pt; and Zr-BTB@Pt and a quaternary ammonium salt ligand are added to methanol to implement a reaction to obtain Zr-BTB@Pt-NH4 +. When used in a photocatalytic reaction, the prepared Zr-BTB@Pt-NH4 + can significantly improve the hydrogen production efficiency of a photocatalytic material.

Description

A photocatalyst with post-modification of charged ligands and a preparation method and application thereof

[0001] Cross-reference to Related Applications

[0002] This application claims priority to Chinese Patent Application No. 202411374762.8, filed on September 29, 2024, entitled "A photocatalyst with post-modification of charged ligands and a preparation method and application thereof", the entire contents of which are incorporated herein by reference. TECHNICAL FIELD

[0003] The present application belongs to the field of photocatalysis, and particularly relates to a photocatalytic material with post-modification of charged ligands and a preparation method and application thereof. BACKGROUND

[0004] Hydrogen energy, as a recognized clean energy, has the characteristics of light weight, high energy density, zero pollution, zero carbon emission, etc., especially the characteristics of zero pollution and zero emission are highly consistent with the current global urgent demand for green and sustainable development, and solar-driven photocatalytic hydrogen production is considered as a feasible means to solve energy crisis and environmental problems.

[0005] However, although the photocatalytic hydrogen production technology has broad prospects, its practical application still faces many challenges, among which the most core and urgent to be solved is the in-depth understanding of the photocatalytic reaction mechanism and the improvement of the efficiency. At present, the specific mechanism of the key links such as photon absorption, electron-hole pair generation and separation, and subsequent surface catalytic reaction in the photocatalytic process is not completely clear, which directly limits the further improvement of photocatalytic efficiency. In addition, although traditional block photocatalytic materials have stable structure, they often have small specific surface area, poor light absorption capacity, low electron migration efficiency and other problems, which lead to low atomic utilization rate and unsatisfactory energy conversion efficiency, resulting in a large waste of valuable solar energy resources.

[0006] On the other hand, metal nanoparticles exhibit extremely high catalytic activity due to their unique surface effect and quantum size effect, providing a new possibility for improving photocatalytic efficiency. However, these nanoparticles are also prone to agglomeration due to their extremely high surface energy during the reaction process, which not only greatly reduces their effective catalytic area, but also may lead to the shielding of active sites, thereby causing the catalyst to be rapidly deactivated, seriously affecting the stability and sustainability of the catalytic reaction.

[0007] Therefore, improving the efficiency of artificial photocatalysts and developing new photocatalytic materials are the core problems faced by the field. SUMMARY

[0008] The present application aims to overcome the above-mentioned shortcomings of the prior art, and provides a post-modified photocatalytic material with charged ligands and a preparation method and application thereof, and solves the problem of agglomeration and deactivation of metal nanoparticles as catalytically active centers in the reaction process.

[0009] To achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0010] The present application provides a preparation method of a post-modified photocatalyst with charged ligands, comprising:

[0011] Zr-BTB, potassium chloroplatinite solution and deionized water are added into ethanol and uniformly mixed for reaction, and Zr-BTB@Pt is obtained after the reaction is completed.

[0012] Zr-BTB@Pt and quaternary ammonium salt ligand are dispersed in methanol for reaction to obtain Zr-BTB@Pt-NH4 + .

[0013] The mass ratio of Zr-BTB, potassium chloroplatinite and deionized water is 15:(3-9):1000.

[0014] The mass ratio of Zr-BTB@Pt and quaternary ammonium salt ligand is 1:(6-10).

[0015] Zr-BTB, potassium chloroplatinite solution and deionized water are added into ethanol and uniformly mixed for reaction, and Zr-BTB@Pt is obtained after the reaction is completed.

[0016] Zr-BTB, potassium chloroplatinite solution and deionized water are added into ethanol and uniformly mixed for reaction, and Zr-BTB@Pt is obtained after the reaction is completed.

[0017] Zr-BTB@Pt and quaternary ammonium salt ligand are dispersed in methanol for reaction to obtain Zr-BTB@Pt-NH4 + , specifically:

[0018] Zr-BTB@Pt and quaternary ammonium salt ligand are dispersed in methanol, and after condensation reflux treatment for 12-16 hours, a second product is obtained, which is washed with methanol and dried to obtain Zr-BTB@Pt-NH4 + .

[0019] The preparation method of Zr-BTB is specifically:

[0020] The zirconium salt and 1,3,5-tris(4-carboxylphenyl) benzene are dissolved in N,N-dimethylformamide, formic acid and water are added to the N,N-dimethylformamide, and the mixture is uniformly dispersed by ultrasonic dispersion to obtain a dispersion liquid, the dispersion liquid is heated to obtain a third product, and the third product is washed with N,N-dimethylformamide and ethanol and dried to obtain Zr-BTB.

[0021] The zirconium salt includes zirconium chloride and anhydrous zirconium oxychloride, and the mass ratio of the zirconium salt to 1,3,5-tris(4-carboxylphenyl) benzene is 1:(1-1.5);

[0022] The heating condition is 48-60 hours of heat preservation in an oven at 110-130 DEG C.

[0023] The quaternary ammonium salt ligand is prepared by the following method:

[0024] The isonicotinic acid and methyl iodide are dissolved in methanol, and after condensation reflux treatment for 40-48 hours, the mixture is cooled to room temperature, filtered to obtain a red solid, washed with acetone until the solid is yellow, and recrystallized with methanol to obtain the quaternary ammonium salt ligand;

[0025] The mass ratio of the isonicotinic acid to methyl iodide is 3:(5-6).

[0026] The application also provides a charged ligand post-modified photocatalyst prepared by the above preparation method.

[0027] The application also provides application of the above charged ligand post-modified photocatalyst in photocatalytic hydrogen production.

[0028] Compared with the prior art, the application has the beneficial effects that:

[0029] The application provides a preparation method of a charged ligand post-modified photocatalytic material, and the application takes Zr-BTB as a model, uniformly encapsulates metal nanoparticles in the Zr-BTB carrier, solves the problem of agglomeration and deactivation of the metal nanoparticles as catalytic active centers in the reaction process by the carrier encapsulation method, grafts a quaternary ammonium salt small molecule on the unsaturated Zr cluster in a coordination bond mode, realizes proton relay by the charged characteristic of the quaternary ammonium salt small molecule to accelerate the electron-hole separation efficiency in the photocatalytic process, and the quaternary ammonium salt small molecule can also realize substrate activation in the surface reaction to further improve the photocatalytic hydrogen production efficiency.

[0030] The charged ligand post-modified photocatalytic material provided by the application uniformly encapsulates metal nanoparticles in the Zr-BTB carrier, and the Zr-BTB carrier is modified by the quaternary ammonium salt ligand, which can greatly improve the electron-hole separation process in the photocatalytic reaction process and improve the photocatalytic efficiency of the photocatalyst.

[0031] The photocatalyst prepared by the application is used for catalytic reaction, and the hydrogen production efficiency can reach 4000 μmol g -1 h -1 The above maximum hydrogen production efficiency can exceed 10000 μmol g -1 h -1 . BRIEF DESCRIPTION OF DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the embodiments of the application, the drawings needed to be used in the embodiments will be briefly introduced as follows:

[0033] Fig. 1 is a transmission electron microscope picture of Zr-BTB@Pt-NH4 prepared in Example 1; +

[0034] Fig. 2 is a comparison chart of photocatalytic hydrogen production efficiency of Zr-BTB@Pt-NH4 prepared in Example 1 and Zr-BTB@Pt prepared in Comparative Example 1; +

[0035] Fig. 3 is a comparison chart of photocatalytic hydrogen production efficiency of Zr-BTB@Pt-NH4 prepared in Examples 2-6; + DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solutions and advantages of the embodiments of the application more clear, the technical solutions of the embodiments of the application will be described clearly and completely in combination with the drawings in the embodiments of the application. Obviously, the described embodiments are part of the embodiments of the application, rather than all the embodiments. The components of the embodiments of the application described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the application provided in the drawings is not intended to limit the scope of the claimed application, but only represents selected embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the application.

[0037] ​​​Currently, metal organic frameworks (MOFs) are widely concerned in the fields of biological medicine, chemical sensing, catalysis, etc. Metal organic frameworks are a kind of porous crystalline material bridged by metal nodes and organic ligands through coordination bonds. In particular, it has the characteristics of clear structure, adjustable pore environment, and flexible composition, which can realize precision on the atomic scale, and is a good model for studying the structure-activity relationship of chemical reactions. At the same time, MOFs also have semiconductor properties, and through the confinement of active metal nanoparticles, the problem of deactivation caused by aggregation of active centers can be effectively alleviated. At the same time, through reasonable modification of MOFs, the electron-hole separation process in the photocatalytic reaction process can be greatly improved, and the photocatalytic efficiency can be improved.

[0038] The application provides a preparation method of a post-modified photocatalytic material with a charged ligand, comprising the following steps:

[0039] Zr-BTB, potassium chloroplatinite solution and deionized water are added into ethanol, uniformly dispersed and reacted to obtain a gray-black powder, denoted as Zr-BTB@Pt;

[0040] Zr-BTB@Pt and quaternary ammonium salt ligand are added into methanol to react to obtain a powder, denoted as Zr-BTB@Pt-NH4 + .

[0041] The application is further explained as follows:

[0042] In some embodiments, the mass ratio of Zr-BTB, potassium chloroplatinite and deionized water is 15:(3-9):1000. It should be noted that when the Pt loading is at a high level, there will be a shielding effect before the Pt nanoparticles, and the atomic utilization rate will decrease, resulting in that the catalytic activity cannot be linearly increased.

[0043] In some embodiments, the mass ratio of Zr-BTB@Pt and quaternary ammonium salt ligand is 1:(6-10). It should be noted that due to the limited coordination ability of the unsaturated Zr cluster in Zr-BTB, when the ratio exceeds this range, the ligand cannot be grafted onto the Zr-BTB carrier after full coordination.

[0044] In some embodiments, Zr-BTB, potassium chloroplatinite solution and deionized water are added into ethanol, and ultrasonic treatment is performed for 30-60 min to obtain a first product, the first product is washed with deionized water and ethanol, and then dried to obtain Zr-BTB@Pt, and the Zr-BTB@Pt is gray-black. In the process of preparing the Zr-BTB@Pt, the platinum ions in the potassium chloroplatinite are reduced to platinum nanoparticles under the action of deionized water, and then the platinum nanoparticles are fixed on the Zr-BTB carrier, so that the reduction of activity caused by the agglomeration or falling off of the nanoparticles during use of the catalyst is prevented, and the stability of the catalyst is improved.

[0045] In some embodiments, the Zr-BTB@Pt and the quaternary ammonium salt ligand are dispersed in methanol, and after condensation reflux treatment for 12-16 hours, the second product is obtained after cooling to room temperature, the second product is washed with methanol, and then dried to obtain Zr-BTB@Pt-NH4+. In the process of preparing the Zr-BTB@Pt-NH4+, the temperature of the reaction is controlled by the condensation reflux process, so that the quaternary ammonium salt ligand is grafted on the unsaturated Zr cluster of the Zr-BTB carrier. +

[0046] The preparation method of the Zr-BTB specifically includes:

[0047] The zirconium salt and 1,3,5-tris(4-carboxylphenyl) benzene are dissolved in N,N-dimethylformamide (DMF), formic acid and water are added into the N,N-dimethylformamide, and ultrasonic dispersion is performed to obtain a dispersion liquid, the dispersion liquid is sealed and placed in an oven at 110-130°C for 48-60 hours, and after cooling to room temperature, the dispersion liquid is washed with DMF and ethanol for 1-3 times and then dried to obtain a white powder, which is denoted as Zr-BTB.

[0048] In some embodiments, the zirconium salt includes zirconium chloride and anhydrous zirconium oxychloride; the mass ratio of the zirconium salt to 1,3,5-tris(4-carboxylphenyl) benzene is 1:(1-1.5); and the mass ratio of formic acid to water is (2-3):1.

[0049] It should be noted that the Zr-BTB carrier prepared by the preparation method of the Zr-BTB carrier provided in the present application has regular porosity, a larger specific surface area, and excellent stability.

[0050] In some embodiments, the preparation method of the quaternary ammonium salt ligand specifically includes:

[0051] Isonicotinic acid and iodomethane are dissolved in methanol, and after condensation reflux treatment for 40-48 hours, the mixture is cooled to room temperature, and a red solid is obtained by filtration, the red solid is washed with acetone until the red solid becomes yellow, and then the quaternary ammonium salt ligand is obtained by recrystallization purification with methanol, and the quaternary ammonium salt ligand is a yellow crystal.

[0052] ​In some embodiments, the mass ratio of isonicotinic acid and iodomethane is 3: (5-6).

[0053] It should be noted that the preparation method of the quaternary ammonium salt ligand provided in the present application can prepare a quaternary ammonium salt ligand with good thermal stability and chemical stability, so that the quaternary ammonium salt ligand can maintain its structure and performance stability in subsequent application.

[0054] In the following examples, unless otherwise specified, each material used can be obtained by ordinary channels; the test method used is a conventional method in the art.

[0055] Example 1

[0056] Zr-BTB: 10 mg of ZrCl4 and 10 mg of 1,3,5-tris (4-carboxyl phenyl) benzene were dissolved in 3 ml of N, N-dimethylformamide, then 1 ml of formic acid and 0.5 ml of deionized water were added, and ultrasonic dispersion was performed to obtain a dispersion liquid, the dispersion liquid was sealed and placed in a 120°C oven for 48 hours, after cooling to room temperature, it was washed twice with DMF and once with ethanol, and then dried to obtain a white powder, which was recorded as Zr-BTB.

[0057] Zr-BTB@Pt: 15 mg of Zr-BTB was dispersed in 5 ml of ethanol, 300 μl of 10 mg / ml potassium chloroplatinite solution and 1 ml of deionized water were added, and ultrasonic treatment was performed for 40 minutes, then it was washed with deionized water and ethanol, and dried to obtain a gray-black powder, which was recorded as Zr-BTB@Pt.

[0058] Quaternary ammonium salt ligand: 15 g of isonicotinic acid and 26 g of iodomethane were dissolved in 70 ml of methanol, and after condensation reflux treatment for 40 hours, it was cooled to room temperature, filtered to obtain a red solid, washed with acetone until the red solid was yellow, and then recrystallized with methanol to obtain a quaternary ammonium salt ligand, which was a yellow crystal.

[0059] Zr-BTB@Pt-NH4 + : 10 mg of Zr-BTB@Pt and 60 mg of quaternary ammonium salt ligand were dispersed in 10 ml of methanol, and condensation reflux treatment was performed for 12 hours, then it was cooled to room temperature, washed with methanol and dried to obtain a powder, which was recorded as Zr-BTB@Pt-NH4 + . The transmission electron microscopy of Zr-BTB@Pt-NH4 + is shown in Figure 1 below. It can be seen that the Pt nanoparticles are uniformly distributed on the two-dimensional Zr-BTB, and the nanoparticle size is between 2.0-3.5 nanometers.

[0060] Example 2:

[0061] Zr-BTB: 10 mg ZrCl4, 10 mg 1,3,5-tri(4-carboxyphenyl) benzene were dissolved in 3 ml N,N-dimethylformamide, then 1 ml formic acid and 0.5 ml deionized water were added, and the mixture was ultrasonically dispersed to obtain a dispersion liquid. The dispersion liquid was sealed and placed in a 120 °C oven for 48 hours. After cooling to room temperature, the mixture was washed twice with DMF and once with ethanol, and then dried to obtain a white powder, which was recorded as Zr-BTB.

[0062] Zr-BTB@Pt: 15 mg Zr-BTB was weighed and dispersed in 5 ml ethanol, 600 μl of 10 mg / ml potassium chloroplatinite solution and 1 ml deionized water were added, and the mixture was ultrasonically treated for 60 minutes. After washing with deionized water and ethanol, the mixture was dried to obtain a gray-black powder, which was recorded as Zr-BTB@Pt.

[0063] Quaternary ammonium salt ligand: 15 g of isonicotinic acid and 26 g of iodomethane were dissolved in 70 ml of methanol. After refluxing by condensation for 48 hours, the mixture was cooled to room temperature, filtered to obtain a red solid, washed with acetone until the red solid became yellow, and then recrystallized with methanol to obtain a yellow crystalline quaternary ammonium salt ligand.

[0064] Zr-BTB@Pt-NH4 + : 10 mg Zr-BTB@Pt and 60 mg quaternary ammonium salt ligand were dispersed in 10 ml methanol, and refluxed by condensation for 12 hours. After cooling to room temperature, the mixture was washed with methanol and dried to obtain a powder, which was recorded as Zr-BTB@Pt-NH4 + -2.

[0065] Example 3:

[0066] Zr-BTB: 10 mg of anhydrous zirconium oxychloride, 12 mg of 1,3,5-tri(4-carboxyphenyl) benzene were dissolved in 3 ml of N,N-dimethylformamide, then 1 ml of formic acid and 0.5 ml of deionized water were added, and the mixture was ultrasonically dispersed to obtain a dispersion liquid. The dispersion liquid was sealed and placed in a 110 °C oven for 55 hours. After cooling to room temperature, the mixture was washed twice with DMF and once with ethanol, and then dried to obtain a white powder, which was recorded as Zr-BTB.

[0067] Zr-BTB@Pt: 15 mg Zr-BTB was weighed and dispersed in 5 ml ethanol, 900 μl of 10 mg / ml potassium chloroplatinite solution and 1 ml deionized water were added, and the mixture was ultrasonically treated for 40 minutes. After washing with deionized water and ethanol, the mixture was dried to obtain a gray-black powder, which was recorded as Zr-BTB@Pt.

[0068] Quaternary ammonium salt ligand: 15 g of isonicotinic acid and 26 g of iodomethane were dissolved in 70 ml of methanol, and after refluxing by condensation for 40 hours, it was cooled to room temperature, and a red solid was obtained by filtration, which was washed with acetone until the red solid became yellow, and then recrystallized and purified with methanol to obtain the quaternary ammonium salt ligand in the form of yellow crystals.

[0069] Zr-BTB@Pt-NH4 + : 10 mg of Zr-BTB@Pt and 60 mg of quaternary ammonium salt ligand were dispersed in 10 ml of methanol, and refluxed by condensation for 13 hours, and then cooled to room temperature and washed with methanol and dried to obtain a powder, which was recorded as Zr-BTB@Pt-NH4 + -3.

[0070] Example 4:

[0071] Zr-BTB: 10 mg of ZrCl4 and 10 mg of 1,3,5-tris(4-carboxyphenyl)benzene were dissolved in 3 ml of N,N-dimethylformamide, and then 1 ml of formic acid and 0.5 ml of deionized water were added, and the mixture was uniformly dispersed by ultrasonic treatment to obtain a dispersion liquid, which was sealed and placed in an oven at 110°C for 60 hours, and then cooled to room temperature, washed twice with DMF, once with ethanol, and dried to obtain a white powder, which was recorded as Zr-BTB.

[0072] Zr-BTB@Pt: 15 mg of Zr-BTB was dispersed in 5 ml of ethanol, and 300 μl of a 10 mg / ml solution of potassium chloroplatinate and 1 ml of deionized water were added, and the mixture was ultrasonically treated for 40 minutes, and then washed with deionized water and ethanol, and dried to obtain a gray-black powder, which was recorded as Zr-BTB@Pt.

[0073] Quaternary ammonium salt ligand: 15 g of isonicotinic acid and 26 g of iodomethane were dissolved in 70 ml of methanol, and after refluxing by condensation for 46 hours, it was cooled to room temperature, and a red solid was obtained by filtration, which was washed with acetone until the red solid became yellow, and then recrystallized and purified with methanol to obtain the quaternary ammonium salt ligand in the form of yellow crystals.

[0074] Zr-BTB@Pt-NH4 + : 10 mg of Zr-BTB@Pt and 80 mg of quaternary ammonium salt ligand were dispersed in 10 ml of methanol, and refluxed by condensation for 16 hours, and then cooled to room temperature and washed with methanol and dried to obtain a powder, which was recorded as Zr-BTB@Pt-NH4 + -4.

[0075] Example 5:

[0076] Zr-BTB: 10 mg ZrCl4, 10 mg 1,3,5-tri(4-carboxyphenyl) benzene were dissolved in 3 ml N,N-dimethylformamide, then 1 ml formic acid and 0.5 ml deionized water were added, and the mixture was ultrasonically dispersed to obtain a dispersion liquid. The dispersion liquid was sealed and placed in a 130 °C oven for 48 hours. After cooling to room temperature, the mixture was washed twice with DMF and once with ethanol, and then dried to obtain a white powder, which was recorded as Zr-BTB.

[0077] Zr-BTB@Pt: 15 mg Zr-BTB was weighed and dispersed in 5 ml ethanol, 300 μl of 10 mg / ml potassium chloroplatinite solution and 1 ml deionized water were added, and the mixture was ultrasonically treated for 60 minutes. After washing with deionized water and ethanol, the mixture was dried to obtain a gray-black powder, which was recorded as Zr-BTB@Pt.

[0078] Quaternary ammonium salt ligand: 15 g of isonicotinic acid and 26 g of iodomethane were dissolved in 70 ml of methanol. After refluxing by condensation for 45 hours, the mixture was cooled to room temperature, filtered to obtain a red solid, washed with acetone until the red solid became yellow, and then recrystallized with methanol to obtain a yellow crystalline quaternary ammonium salt ligand.

[0079] Zr-BTB@Pt-NH4 + : 10 mg Zr-BTB@Pt and 100 mg quaternary ammonium salt ligand were dispersed in 10 ml of methanol, and refluxed by condensation for 16 hours. After cooling to room temperature, the mixture was washed with methanol and dried to obtain a powder, which was recorded as Zr-BTB@Pt-NH4 + -5.

[0080] Example 6:

[0081] Zr-BTB: 10 mg ZrCl4, 10 mg 1,3,5-tri(4-carboxyphenyl) benzene were dissolved in 3 ml N,N-dimethylformamide, then 1 ml formic acid and 0.5 ml deionized water were added, and the mixture was ultrasonically dispersed to obtain a dispersion liquid. The dispersion liquid was sealed and placed in a 130 °C oven for 48 hours. After cooling to room temperature, the mixture was washed twice with DMF and once with ethanol, and then dried to obtain a white powder, which was recorded as Zr-BTB.

[0082] Zr-BTB@Pt: 15 mg Zr-BTB was weighed and dispersed in 5 ml ethanol, 300 μl of 10 mg / ml potassium chloroplatinite solution and 1 ml deionized water were added, and the mixture was ultrasonically treated for 60 minutes. After washing with deionized water and ethanol, the mixture was dried to obtain a gray-black powder, which was recorded as Zr-BTB@Pt.

[0083] Quaternary ammonium salt ligand: 15 g of isonicotinic acid and 26 g of methyl iodide were dissolved in 70 ml of methanol, and after refluxing by condensation for 40 hours, it was cooled to room temperature, and a red solid was obtained by filtration, which was washed with acetone until the red solid became yellow, and then recrystallized with methanol to obtain the quaternary ammonium salt ligand in the form of yellow crystals.

[0084] Zr-BTB@Pt-NH4 + : 10 mg of Zr-BTB@Pt and 60 mg of quaternary ammonium salt ligand were dispersed in 10 ml of methanol, and refluxed by condensation for 14 hours, and then cooled to room temperature and washed with methanol and dried to obtain a powder, which was recorded as Zr-BTB@Pt-NH4 + -6.

[0085] Comparative Example 1

[0086] This comparative example was prepared according to the method of Example 1, and Zr-BTB@Pt was not modified with a quaternary ammonium salt ligand.

[0087] Photocatalytic hydrogen production experiment

[0088] The catalysts prepared in the examples and comparative examples were respectively applied to the catalytic reaction, and the specific operation was as follows:

[0089] The photocatalytic reaction was carried out in a 70 ml photocatalytic reactor, and the light source was a xenon lamp with a wavelength of 390 nm to 780 nm.

[0090] 10 mg of tris(2,2'-bipyridyl)ruthenium(II) and 10 mg of catalyst prepared in the examples and comparative examples were respectively dispersed in 18 ml of acetonitrile, and 1 ml of deionized water and 0.5 ml of triethylamine were added to carry out the catalytic reaction.

[0091] Result analysis:

[0092] As shown in Figure 2, it reflects the hydrogen production efficiency of the photocatalytic reaction of Example 1 and Comparative Example 1; the photocatalytic reaction test shows that the hydrogen production efficiency of Zr-BTB@Pt-NH4 + is 4872.1 μmol g -1 h -1 , and the hydrogen production efficiency of the Zr-BTB@Pt photocatalyst without post-modification of the quaternary ammonium salt ligand is 2650.5 μmol g -1 h -1 . It can be seen that the method of post-modification with a charged ligand significantly improves the hydrogen production efficiency of the photocatalytic material.

[0093] It can be found from the hydrogen production performance of the two photocatalysts of Comparative Example 1 and Comparative Example 1 that the photocatalytic hydrogen production efficiency is significantly improved after the quaternary ammonium salt ligand is modified under the condition that the loading of active substance Pt nanoparticles is consistent. Photocatalysis mainly includes three processes, namely, light excitation, electron-hole separation, and finally surface reaction. Due to the electric charge of the quaternary ammonium salt ligand, it acts as a proton relay in the reaction process, improves the second process of photocatalytic reaction, accelerates charge transfer, and improves the efficiency of the catalyst. In addition, the charged ligand can also accelerate the occurrence of surface reaction, polarize water molecules, and improve the surface reaction rate. The two factors work together to improve the photocatalytic hydrogen production efficiency.

[0094] As shown in FIG. 3, the hydrogen production efficiency of the photocatalytic reaction of the catalyst prepared in Examples 2-6 is reflected. The hydrogen production efficiency of Examples 2-6 can reach 4000 μmol g -1 h -1 The above, the hydrogen production efficiency of the photocatalytic reaction of the catalyst prepared in Example 3 is more than 10000 μmol g -1 h -1 .

[0095] The endpoints of the ranges and any values disclosed in this application are not limited to the precise values recited. The ranges or values should be interpreted as being approximate to the exact ranges or values. For ranges of values, the endpoints of the ranges are combined with the individual points to form new ranges or values, which are to be considered as being specifically disclosed. In the following, the technical solutions can be combined with each other to form new technical solutions, which are also to be considered as being specifically disclosed.

[0096] The above examples are only used to illustrate the technical solutions of the present application, not to limit it. Although the present application has been described in detail with reference to the above examples, the specific embodiments of the present application can still be modified or replaced by those skilled in the art, and any modification or replacement that does not deviate from the spirit and scope of the present application is within the scope of protection of the claims of the application.

Claims

1. A method for preparing a photocatalyst post-modified with a charged ligand, characterized by, Comprising: Zr-BTB, potassium chloroplatinite solution and deionized water are added into ethanol and mixed uniformly to react, and Zr-BTB@Pt is obtained after the reaction is completed; Zr-BTB@Pt and quaternary ammonium salt ligand were dispersed in methanol to react to obtain Zr-BTB@Pt-NH4 + .

2. The method of claim 1, wherein the method is characterized by, The mass ratio of the Zr-BTB, potassium chloroplatinite and deionized water is 15:(3-9):1000.

3. The method of claim 1, wherein the method is characterized by, The mass ratio of the Zr-BTB@Pt and the quaternary ammonium salt ligand is 1:(6-10).

4. The method of claim 1, wherein the method is characterized by, The Zr-BTB, potassium chloroplatinite solution and deionized water are added into ethanol and mixed uniformly to react, and Zr-BTB@Pt is obtained after the reaction is completed, specifically: Zr-BTB, potassium chloroplatinite solution and deionized water are added into ethanol and mixed uniformly to react, and Zr-BTB@Pt is obtained after the reaction is completed, specifically:

5. The method of claim 1, wherein the method is characterized by, The Zr-BTB@Pt and quaternary ammonium salt ligand are dispersed in methanol to react to obtain Zr-BTB@Pt-NH4 + Specifically, Zr-BTB@Pt and the quaternary ammonium salt ligand are dispersed in methanol, and after condensation reflux treatment for 12-16 hours, a second product is obtained. The second product is washed with methanol and dried again to obtain Zr-BTB@Pt-NH4 + .

6. The method of claim 1, wherein the method is characterized by, The preparation method of the Zr-BTB is specifically: The zirconium salt and 1,3,5-tris(4-carboxylphenyl) benzene are dissolved in N,N-dimethylformamide, formic acid and water are then added into the N,N-dimethylformamide, and the dispersion liquid is obtained by ultrasonic dispersion, the third product is obtained by heating the dispersion liquid, and the third product is washed with N,N-dimethylformamide and ethanol and dried to obtain the Zr-BTB after cooling to room temperature.

7. The method of claim 6, wherein the method is characterized by, The zirconium salt includes zirconium chloride and anhydrous zirconium oxychloride, and the mass ratio of the zirconium salt and 1,3,5-tris(4-carboxylphenyl) benzene is 1:(1-1.5); The heating condition is 110-130°C in an oven for 48-60 hours.

8. The method of claim 1, wherein the method is characterized by, The quaternary ammonium salt ligand is prepared by the following method: Isonicotinic acid and iodomethane are dissolved in methanol, and the red solid is obtained by condensation reflux treatment for 40-48 hours, cooling to room temperature and filtration, and the quaternary ammonium salt ligand is obtained by recrystallization with methanol after the solid is washed with acetone until the solid turns yellow; The mass ratio of the isonicotinic acid and iodomethane is 3:(5-6).

9. A light catalyst with a post-modified charged ligand prepared by the preparation method of any one of claims 1-8.

10. Application of the light catalyst with a post-modified charged ligand of claim 9 in photocatalytic hydrogen production.

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