CN109134877B - A kind of photofunctional composite material, its preparation method and tandem photocatalytic application - Google Patents

Abstract

The invention discloses a photofunctional composite material, a preparation method thereof and a series photocatalysis application. The photofunctional composite material has the following chemical formula: [Cu ₂ (NTB) ₂ (W ₆ O ₁₉ )]·DMF, NTB is 4-(4H-1,2,4-triazole-4-base)- N,N-bis[4-(4H-1,2,4-triazol-4-yl)phenyl]-aniline, the simplified structural formula of NTB is as follows:

The photofunctional composite material is crystallized in the monoclinic system, the space group is P2(1)/c, and the unit cell parameter is

The photofunctional composite material of the invention has the tandem catalytic performance of photocatalytically decomposing water to generate oxygen and selectively oxidizing sulfide to prepare sulfoxide, and the preparation method is simple and high in yield.

Description

A kind of photofunctional composite material, its preparation method and tandem photocatalytic application

technical field

The invention relates to a photofunctional composite material, in particular to a photofunctional POM@PCP composite material and a preparation method thereof, as well as the application of the composite material in tandem photocatalysis, and belongs to the technical field of photocatalytic materials.

Background technique

Sulfoxide and sulfone are produced by oxidation of sulfide, among which sulfoxides are a class of very useful intermediates in organic synthesis, which are used in antiulcer (proton pump inhibitors), antibacterial, antifungal, antiatherosclerotic, and Insect drugs, antihypertensives, cardiac drugs, psychotropic drugs and vasodilators play an important role. Sulfoxides are generally prepared by selective oxidation of the corresponding sulfides, usually using halogen, nitric or nitrate oxidation systems. However, it has been noticed that these oxidant oxidation systems are accompanied by many disadvantages, such as long reaction time, harsh reaction conditions, expensive oxidants, high toxicity, many by-products, and serious pollution. In recent years, people have been working hard to develop green, mild and economical selective catalytic oxidation systems, among which the green and clean catalytic oxidation systems using molecular oxygen as oxidants have begun to receive attention.

The use of artificially simulated photosynthesis systems to split water to produce oxygen is an economical and promising method, and has attracted the attention of many researchers. One of the half-reactions of water splitting is water oxidation, which has always been a bottleneck restricting water splitting due to its complex process. Therefore, finding efficient and stable water oxidation catalysts has become the key to breaking through this bottleneck.

In recent years, the tandem reaction synthesis strategy with the characteristics of greenness, high efficiency and atom economy has aroused strong interest in academia and industry. Many important achievements have been achieved, and it has become one of the frontier fields of organic synthetic chemistry research. Compared with the traditional step-by-step synthesis, the series reaction has more advantages, such as eliminating the separation and purification process of intermediate products, and enabling multiple reaction processes to occur in the same reactor. Catalytic multi-component tandem reactions can efficiently construct complex and structurally diverse organic molecules from simple raw materials in one step, which has attracted great interest and extensive attention from chemists. But so far, there is no report on materials catalyzing multi-component tandem reactions.

SUMMARY OF THE INVENTION

The main purpose of the present invention is to provide a photofunctional POM@PCP composite material and a preparation method thereof, so as to overcome the deficiencies of the prior art.

Another object of the present invention is to provide the application of the aforementioned photofunctional POM@PCP composite material in tandem photocatalysis.

In order to realize the foregoing invention purpose, the technical scheme adopted in the present invention includes:

The embodiment of the present invention provides a photo-functional composite material, which has the following chemical formula: [Cu ₂ (NTB) ₂ (W ₆ O ₁₉ )]·DMF, wherein DMF is N,N′-dimethylformaldehyde Amide, NTB is 4-(4H-1,2,4-triazol-4-yl)-N,N-bis[4-(4H-1,2,4-triazol-4-yl)phenyl] -Aniline, the simplified structure of NTB is as follows:

β＝111.272(8)°，

The photofunctional composite material is crystallized in a monoclinic system, the space group is P2(1)/c, and the unit cell parameter is

β=111.272(8)°,

Further, the basic structure of the photofunctional composite material is a three-dimensional network structure, wherein Cu ^I ions are respectively coordinated with four nitrogen atoms from four triazole groups, and the ligand NTB and the Cu ^I ions form a three-dimensional network structure, Crystallographically, two types of regular channels are displayed along the b-axis. The oxidized [W ₆ O ₁₉ ] ² -polyacid anion occupies one of the channels, and the other is convenient for photocatalytic tandem reaction experiments.

The embodiment of the present invention also provides the preparation method of the photo-functional composite material, which comprises: the molar ratio of polyoxometalate, copper salt and NTB ligand in a molar ratio of 1:5:5 to 1:5:10 It is fully mixed in a solvent, and then cured at 110-130° C. for 60-84 hours to obtain orange-yellow bulk crystals, which are the photofunctional composite materials.

The embodiments of the present invention also provide the application of the photofunctional composite material in photocatalytic water splitting or selective photocatalytic oxidation of sulfide to synthesize sulfoxide.

Further, the embodiments of the present invention also provide the use of the photofunctional composite material in preparing oxygen and selectively preparing sulfoxide.

The embodiment of the present invention also provides a photocatalytic water splitting oxygen production catalyst, which includes the aforementioned photofunctional composite material.

Further, an embodiment of the present invention also provides a photocatalytic water splitting method for producing oxygen, comprising: using the aforementioned photofunctional composite material as a catalyst, sodium persulfate as an electron acceptor, [Ru(bpy) ₃ ]Cl ₂ As a photosensitizer, using visible light as a light source, in a boric acid buffer system, photocatalytic decomposition of water is carried out to obtain oxygen.

The embodiment of the present invention also provides a catalyst for photocatalytic tandem synthesis of sulfoxide, which comprises the aforementioned photofunctional composite material.

Further, an embodiment of the present invention also provides a method for tandem photocatalytic decomposition of water for oxygen production and selective synthesis of sulfoxide, which includes: using the aforementioned photofunctional composite material as a catalyst, and an aryl sulfide as a reaction substrate, Sodium persulfate was used as electron acceptor, [Ru(bpy) ₃ ]Cl ₂ was used as photosensitizer, and visible light was used as light source to conduct tandem photocatalytic reaction in boric acid buffer system.

Compared with the prior art, the advantages of the present invention include:

(1) The photofunctional POM@PCP composite material provided by the present invention realizes the tandem reaction of photocatalytic decomposition of water for oxygen production and selective preparation of sulfoxide for the first time, and has good performance in the synthesis of drugs such as antihypertensive, cardiac drugs and vasodilators. application prospects;

(2) The NTB ligand used in the present invention not only has a three-dimensional propeller structure, rich electrons and structural stability, but also has extremely high fluorescence performance and photoluminescence efficiency. plays a vital role in the catalytic process;

(3) The Lindqvist type polyacid filled in the pores of the photofunctional POM@PCP composite material provided by the present invention enhances the stability of the structure and chemical properties of the composite material, thereby improving the photocatalytic efficiency and reusability;

(4) The preparation process of the photofunctional POM@PCP composite material provided by the present invention has simple synthesis steps, easy operation, low energy consumption, high yield, cheap and easily available synthetic raw materials, mild reaction conditions and good selectivity, and is suitable for industrial large-scale The need for mass production.

Description of drawings

FIG. 1 is a schematic diagram of the tandem photocatalysis of [Cu ₂ (NTB) ₂ (W ₆ O ₁₉ )]·DMF obtained in Example 1 of the present invention.

2 is a crystal structure diagram of [Cu ₂ (NTB) ₂ (W ₆ O ₁₉ )]·DMF obtained in Example 1 of the present invention.

3 is a transient photocurrent-time graph of [Cu ₂ (NTB) ₂ (W ₆ O ₁₉ )]·DMF obtained in Example 1 of the present invention.

FIG. 4 is a graph showing the variation of oxygen production with time of [Cu ₂ (NTB) ₂ (W ₆ O ₁₉ )]·DMF obtained in Example 1 of the present invention and a diagram of the photocatalytic oxygen production mechanism.

Detailed ways

In view of the deficiencies in the prior art, the inventor of the present invention has been able to propose the technical solution of the present invention after long-term research and extensive practice. The technical solution, its implementation process and principle will be further explained below.

Polyoxometalates (POMs) are referred to as polyacids, which are a class of polyoxometallic compounds formed by the former transition metal oxygen clusters as the basic units. Due to the incomparable properties of polyoxometalates in terms of physical and chemical properties, they have been widely used in catalysis, medicine, nanotechnology and materials science. In addition, Porous Coordination Polymers (PCPs) have advantages such as pore structure similar to molecular sieves, large specific surface area, tunability of structure and size, and excellent thermal and chemical stability. PCPs materials have been applied in the fields of heterogeneous catalysis, separation and purification, ion exchange and gas storage.

The organic combination of water splitting oxygen production reaction and thioether oxidation reaction constitutes a series catalytic reaction, which is a new method for the selective preparation of sulfoxide.

An aspect of the embodiments of the present invention provides a photo-functional POM@PCP composite material, which has the following chemical formula: [Cu ₂ (NTB) ₂ (W ₆ O ₁₉ )]·DMF, wherein DMF is N,N '-Dimethylformamide, NTB is 4-(4H-1,2,4-triazol-4-yl)-N,N-bis[4-(4H-1,2,4-triazol-4 - base) phenyl]-aniline, the structural formula of NTB is as follows:

β＝111.272(8)°，

The photofunctional POM@PCP composite material is crystallized in a monoclinic system, the space group is P2(1)/c, and the unit cell parameter is

β=111.272(8)°,

Further, the basic structure of the photofunctional POM@PCP composite material is a three-dimensional network structure, in which Cu ^I ions are respectively coordinated with four nitrogen atoms from four triazole groups, and the ligand NTB and Cu ^I ions form a three-dimensional network. The network structure shows two types of regular pores along the b-axis in crystallography. The oxidized [W ₆ O ₁₉ ] ² -polyacid anion occupies one of the pores, and the other is convenient for the photocatalytic tandem reaction. experiment.

Another aspect of the embodiments of the present invention provides the aforementioned method for preparing a photofunctional composite material, which comprises: mixing polyoxometalate, copper salt and NTB in a molar ratio of 1:5:5 to 1:5:10 The ligands are fully mixed in the solvent, and then cured at 110-130° C. for 60-84 hours to obtain orange-yellow bulk crystals, which are the photofunctional composite materials.

In some embodiments, the molar ratio of the polyoxometalate, the copper salt and the NTB ligand is (0.01-0.05):(0.05-0.10):(0.05-0.10). Specifically, the polyoxometalate The amounts of the acid salts, copper salts, and NTB ligands were 0.01 to 0.05 mmol, 0.05 to 0.10 mmol, and 0.05 to 0.10 mmol, respectively.

Further, the copper salt includes hydrated copper nitrate, preferably copper nitrate trihydrate, but not limited thereto.

Further, the polyoxometalate includes (TBA) ₄ [W ₁₀ O ₃₂ ], but is not limited thereto.

Further, the solvent includes DMF, water, etc., but is not limited thereto.

In some embodiments, the preparation method includes: uniformly mixing the copper salt, the TPB ligand and the polyoxometalate to obtain a mixture, and then adding it to a solvent, wherein the amount ratio of the mixture to the solvent is 60 mg: 2 mL～ 90 mg: 5 mL, adjust the pH of the system to 2.5-3.0 with 1-2 mol·L ^-1 HCl, stir at room temperature for 20-40 min, mix thoroughly, and then perform curing treatment.

In some specific implementation cases, the preparation method includes: uniformly mixing copper nitrate trihydrate, NTB ligand and (TBA) ₄ [W ₁₀ O ₃₂ ] polyacid to obtain a mixture, and then adding it to DMF and mixing with water In the solvent, stir at room temperature for 20-40 min, adjust the pH of the system to 2.5-3.0 with 1-2 mol·L ^-1 HCl, and obtain a mixed solution; then bake at 120 °C for 60-84 h, and then separate the solid; use DMF washes the above solid for 3 to 5 times to obtain an orange bulk crystal material, which is the photofunctional POM@PCP composite material.

Another aspect of the embodiments of the present invention also provides the application of the aforementioned photofunctional POM@PCP materials in photocatalytic water splitting and selective photocatalytic oxidation of sulfide to synthesize sulfoxide.

Preferably, the application includes the application in series photocatalytic splitting of water to generate oxygen and selective oxidation of sulfide to prepare sulfoxide.

Further, the embodiments of the present invention also provide the use of the photofunctional POM@PCP material in preparing oxygen and selectively preparing sulfoxide.

Another aspect of the embodiments of the present invention also provides a photocatalytic water splitting catalyst for oxygen production, which includes the aforementioned photofunctional composite material.

Further, another aspect of the embodiments of the present invention also provides a method for photocatalytic decomposition of water for oxygen production, comprising: using the aforementioned photofunctional composite material as a catalyst, sodium persulfate as an electron acceptor, [Ru(bpy) ₃ ]Cl ₂ was used as a photosensitizer, and visible light was used as the light source. In the boric acid buffer system, the photocatalytic oxygen production experiment was carried out, and the water was photocatalytically decomposed to obtain oxygen.

Further, in some specific implementation cases, the method for photocatalytic decomposition of water to produce oxygen includes: using the photofunctional POM@PCP material as a catalyst and sodium persulfate (Na ₂ S ₂ O ₈ ) as an electron Acceptor, ruthenium terbipyridine ([Ru(bpy) ₃ ]Cl ₂ ) was used as photosensitizer, LED lamp was used as light source, the total volume of sodium borate buffer solution (8.0 × 10 ^-2 M) was 10 mL, and the dehydration was carried out in argon atmosphere. The gas was treated for 10 min, and then the photocatalytic reaction was carried out under the irradiation of an LED lamp. The generated oxygen was detected by GC7900 gas chromatography, and argon was used as the carrier gas.

Another aspect of the embodiments of the present invention also provides a catalyst for photocatalytic tandem synthesis of sulfoxide, which comprises the aforementioned photofunctional composite material.

Further, another aspect of the embodiments of the present invention also provides a method for tandem photocatalytic decomposition of water for oxygen production and selective synthesis of sulfoxide, comprising: using the aforementioned photofunctional composite material as a catalyst, and an aryl sulfide as a The reaction substrate, sodium persulfate as the electron acceptor, [Ru(bpy) ₃ ]Cl ₂ as the photosensitizer, and visible light as the light source, in a boric acid buffer system, the tandem photocatalytic reaction is carried out.

Further, in some specific implementation cases, the preparation method of the tandem photocatalysis includes: using the photofunctional POM@PCP material as a catalyst, and aryl sulfide (Ar-S-Ar) as a reaction substrate compound, sodium persulfate (Na ₂ S ₂ O ₈ ) as electron acceptor, ruthenium terpyridine ([Ru(bpy) ₃ ]Cl ₂ ) as photosensitizer, LED lamp as light source, sodium borate buffer solution (8.0×10 ^–2 M) in a total volume of 10 mL, degassed for 10 min in an argon atmosphere, and then subjected to photocatalytic reaction under the irradiation of an LED lamp, followed by separation, extraction, concentration, and NMR testing.

In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention will be described in further detail below in conjunction with specific embodiments. The methods in the following embodiments, unless otherwise specified, are conventional methods in the art.

Example 1: Preparation of photofunctional POM@PCP composites

(TBA) ₄ [W ₁₀ O ₃₂ ] (33.2 mg, 0.01 mmol), Cu(NO ₃ ) ₂ .3H ₂ O (12.1 mg, 0.05 mmol) and NTB (22.3 mg, 0.05 mmol) were added to N,N - Stir in a mixture of dimethylformamide (DMF, 2.0 mL) and water (0.5 mL), adjust the pH of the system to 2.6 with 1 mol·L ^-1 HCl, stir at room temperature for 20 min, and then add the above suspension Add it to a 25mL polytetrafluoroethylene reaction kettle, bake at 120°C for 72h, and finally cool to room temperature to obtain orange-yellow bulk crystals, which are washed three times with DMF and dried at room temperature. The yield is about 49%.

Example 2: Preparation of photofunctional POM@PCP composites

(TBA) ₄ [W ₁₀ O ₃₂ ] (33.2 mg, 0.01 mmol), Cu(NO ₃ ) ₂ .3H ₂ O (12.1 mg, 0.05 mmol) and NTB (44.6 mg, 0.10 mmol) were added to N,N - Stir in a mixture of dimethylformamide (DMF, 3.0 mL) and water (2.0 mL), adjust the pH of the system to 2.5 with 1 mol·L ^-1 HCl, stir at room temperature for 30 min, and then add the above suspension Add it to a 25mL polytetrafluoroethylene reaction kettle, bake at 110°C for 84h, and finally cool to room temperature to obtain orange-yellow bulk crystals, which are washed three times with DMF and dried at room temperature. The yield is about 51%.

Example 3: Preparation of photofunctional POM@PCP composites

(TBA) ₄ [W ₁₀ O ₃₂ ] (33.2 mg, 0.01 mmol), Cu(NO ₃ ) ₂ .3H ₂ O (12.1 mg, 0.05 mmol) and NTB (26.8 mg, 0.06 mmol) were added to N,N - Stir in a mixture of dimethylformamide (DMF, 3.0 mL) and water (1.0 mL), adjust the pH of the system to 3.0 with 1 mol·L ^-1 HCl, stir at room temperature for 40 min, and then add the above suspension Add it to a 25mL polytetrafluoroethylene reaction kettle, bake at 130°C for 60h, and finally cool to room temperature to obtain orange-yellow bulk crystals, which are washed three times with DMF and dried at room temperature. The yield is about 50%.

Example 4: Preparation of photofunctional POM@PCP composites

(TBA) ₄ [W ₁₀ O ₃₂ ] (33.2 mg, 0.01 mmol), Cu(NO ₃ ) ₂ .3H ₂ O (12.1 mg, 0.05 mmol) and NTB (35.7 mg, 0.08 mmol) were added to N,N - Stir in a mixture of dimethylformamide (DMF, 2.0 mL) and water (1.0 mL), adjust the pH of the system to 2.8 with 1 mol·L ^-1 HCl, stir at room temperature for 25 min, and then add the above suspension Add it to a 25mL polytetrafluoroethylene reactor, bake at 115°C for 75h, and finally cool to room temperature to obtain orange-yellow bulk crystals, which are washed three times with DMF and dried at room temperature. The yield is about 49%.

Example 5: Preparation of photofunctional POM@PCP composites

(TBA) ₄ [W ₁₀ O ₃₂ ] (33.2 mg, 0.01 mmol), Cu(NO ₃ ) ₂ .3H ₂ O (12.1 mg, 0.05 mmol) and NTB (31.2 mg, 0.07 mmol) were added to N,N - Stir in a mixture of dimethylformamide (DMF, 2.5 mL) and water (0.5 mL), adjust the pH of the system to 2.7 with 1 mol·L ^-1 HCl, stir at room temperature for 35 min, and then mix the above suspension Add it to a 25mL polytetrafluoroethylene reaction kettle, bake at 120°C for 72h, and finally cool to room temperature to obtain orange-yellow bulk crystals, which are washed three times with DMF and dried at room temperature. The yield is about 48%.

Example 6: Preparation of photofunctional POM@PCP composites

(TBA) ₄ [W ₁₀ O ₃₂ ] (33.2 mg, 0.01 mmol), Cu(NO ₃ ) ₂ .3H ₂ O (12.1 mg, 0.05 mmol) and NTB (40.1 mg, 0.09 mmol) were added to N,N - Stir in a mixture of dimethylformamide (DMF, 2.5 mL) and water (1.0 mL), adjust the pH of the system to 2.6 with 1 mol·L ^-1 HCl, stir at room temperature for 30 min, and then add the above suspension Add it to a 25mL polytetrafluoroethylene reactor, bake at 125°C for 65h, and finally cool to room temperature to obtain orange-yellow bulk crystals, which are washed three times with DMF and dried at room temperature. The yield is about 47%.

The photo-functional POM@PCP composite material obtained in Example 1 of the present invention is further characterized, and its process and results are as follows:

(1) Determination of crystal structure

Under a polarizing microscope, single crystals of suitable size were selected for X-ray single crystal diffraction experiments at room temperature. Crystallographic data were collected on an Agilent Supernova X-ray single crystal diffractometer equipped with a graphite monochromator and a copper target light source. The analysis of the single crystal structure was calculated by the SHELXS (direct method) program in the Olex2 software, and the refinement of the structure was calculated by the SHELXL program (full matrix least squares) in the Olex2 software. All non-hydrogen atoms are refined by anisotropy. Hydrogen atoms are added to the structure by geometric hydrogenation, and the parameter self-tuning model is used for refinement. The detailed crystal measurement data is shown in Table 1, the important bond length and bond angle data are shown in Table 2 and Table 3, and the crystal structure is shown in Table 1. Figures 1 and 2.

Table 1 Main crystallographic data of the photofunctional POM@PCP composite material obtained in Example 1

^a R ₁ =Σ||F _o |–|F _c ||/Σ|F _o |. ^b wR ₂ =|Σw(|F _o | ² –|F _c | ² )|/Σ|w(F _o ) ² | ^1/2 , where w=1/[σ ² (F _o ² )+(aP) ² +bP].P=(F _o ² +2F _c ² )/3.

Table 2 Main bond lengths of the photofunctional POM@PCP composites obtained in Example 1

*Symmetric opcodes: #1–x,–y+1,–z+1; #2–x+2,–y,–z+1; #3x–1,–y+1/2,z–1 /2; #4x–1,y,z; #5x+1,–y+1/2,z+1/2; #6x+1,y,z.

Table 3 Main bond angles of the photofunctional POM@PCP materials obtained in Example 1 [°]*

*Symmetric opcodes: #1–x,–y+1,–z+1; #2–x+2,–y,–z+1; #3x–1,–y+1/2,z–1 /2; #4x–1,y,z; #5x+1,–y+1/2,z+1/2; #6x+1,y,z.

(2) Transient photocurrent-time curve test

XM型电化学工作站上测得。采用标准的三电极系统，工作电极按照常规方法制得，0.1mol·L^–1的KCl溶液作为支持电解质。300W氙灯作为激发光源。The transient photocurrent-time curve test results are in

Measured on XM electrochemical workstation. Using a standard three-electrode system, the working electrode was prepared according to the conventional method, and 0.1 mol·L ^-1 KCl solution was used as the supporting electrolyte. A 300W xenon lamp was used as the excitation light source.

Figure 3 is the transient photocurrent-time graph of [Cu ₂ (NTB) ₂ (W ₆ O ₁₉ )]·DMF, and the photofunctional POM@PCP materials (named: CuW-NTB) were tested respectively. , the transient photocurrent-time curves of CuW-NTB+[Ru(bpy) ₃ ]Cl ₂ and bare electrodes, as shown in Figure 3: in the process of photocatalytic water splitting to produce oxygen, the photofunctional POM@PCP material to the role of photocatalysts.

(3) Photocatalysis test

(a) Photocatalytic decomposition of water for oxygen production test

分子筛(2m×3mm)和热导检测器的GC7900气相色谱检测，氩气作为载气。通过外标法计算出产氧量。The photocatalytic water splitting experiment was measured by PL-LED100_ high-power LED light source after irradiation. The photocatalytic oxygen production test was carried out in a 25 mL quartz glass bottle. The photofunctional POM@PCP material was used as a catalyst (5.0 mg), sodium persulfate was used as an electron acceptor (Na ₂ S ₂ O ₈ , 6.0 mg), and ruthenium terpyridine was used as a photosensitizer ([Ru(bpy) ₃ ). ]Cl ₂ , 10.0mg), with LED lamp as light source, sodium borate buffer solution system (8.0×10 ^-2 M, 10mL, pH=9), degassed in argon atmosphere for 10min, and then in an LED lamp (light Intensity=16mW, beam diameter=2cm, cut-off filter λ≥420nm) photocatalytic reaction is carried out under irradiation, and the generated oxygen passes through the

Molecular sieves (2m×3mm) and GC7900 gas chromatography with thermal conductivity detector were used for detection, and argon was used as carrier gas. The oxygen production was calculated by the external standard method.

Figure 4 is a graph showing the change of oxygen production with time of [Cu ₂ (NTB) ₂ (W ₆ O ₁₉ )]·DMF (named as: CuW-NTB) and the photocatalytic oxygen production mechanism. Within 0-25min, the oxygen production of the material increased with time; within 25-30min, its oxygen production remained basically unchanged.

(b) One-pot tandem photocatalytic test

The tandem photocatalysis experiment was measured by PL-LED100_ high-power LED light source after irradiation. Tandem photocatalytic tests were performed in 25 mL quartz glass vials. The photofunctional POM@PCP material was used as the catalyst (5.0 mg), aryl sulfide as the reaction substrate (Ar-S-Ar, 8.0 μmol), and sodium persulfate as the electron acceptor (Na ₂ S ₂ O ₈ , 6.0mg), ruthenium terpyridine as photosensitizer ([Ru(bpy) ₃ ]Cl ₂ , 10.0mg), LED lamp as light source, sodium borate buffer solution system (8.0×10 ^{– 2} M, 10mL, pH= 9), degassed in argon atmosphere for 10min, then irradiated with LED lamp (light intensity=16mW, beam diameter=2cm, cut-off filter λ≥420nm) for 30min, removed catalyst, extracted and separated, concentrated by rotary evaporation, light The catalytic yield was characterized by ¹ HNMR, and the test results are shown in Table 4.

Table 4 Conversion efficiency of photofunctional POM@PCP composites for tandem photocatalysis

To sum up, the photo-functional POM@PCP composite material of the present invention realizes the tandem reaction application of photocatalytic decomposition of water for oxygen production and selective preparation of sulfoxide for the first time. It has good application prospects; and the preparation process has simple synthesis steps, easy operation, low energy consumption, high yield, cheap and easily available synthetic raw materials, mild reaction conditions, and good selectivity, and is suitable for industrial large-scale production. The Lindqvist-type polyacids filled in the pores of the functional POM@PCP composites enhanced the structural and chemical stability of the composites, thereby improving the photocatalytic efficiency and reusability. In particular, the NTB ligand of the present invention not only has a three-dimensional propeller structure, rich electrons and structural stability, but also has extremely high fluorescence performance and photoluminescence efficiency. plays a crucial role in the photocatalytic process.

In addition, the inventors of the present application also conducted experiments with other raw materials and conditions listed in this specification with reference to the methods of Examples 1 to 6, and also obtained a series reaction with photocatalytic decomposition of water for oxygen production and selective preparation of sulfoxide. Applied photofunctional POM@PCP composites.

Using the same characterization method to characterize the products obtained in the remaining examples, test results similar to those in Example 1 can also be obtained.

It should be understood that the above-mentioned embodiments are only intended to illustrate the technical concept and characteristics of the present invention, and the purpose thereof is to enable those who are familiar with the art to understand the content of the present invention and implement it accordingly, and cannot limit the protection scope of the present invention. All equivalent changes or modifications made according to the spirit of the present invention should be included within the protection scope of the present invention.

Claims (13)

1. An optical functional composite material, characterized in that it has the following chemical formula: [ Cu ]₂(NTB)₂(W₆O₁₉)]DMF, wherein DMF is N, N-dimethylformamide and NTB is 4- (4)H-1,2, 4-triazol-4-yl) -N, N-bis [4- (4)H-1,2, 4-triazol-4-yl) phenyl]Aniline, NTB, has the following structural formula:

；

the optical functional composite material is crystallized in monoclinic system with space group ofP2(1)/cCell parameter ofa = 16.4114(5) Å，b = 8.7003(3) Å，c = 25.2295(10) Å，α=90.00 ^o，β = 108.016(4) ^o，γ=90.00 ^o，V= 3425.7(2) ų。

2. The optical functional composite of claim 1, characterized in that: the basic structure of the optical functional composite material is a three-dimensional network structure, wherein Cu^IThe ions are coordinated with four nitrogen atoms from four triazolyl groups respectively, and the ligands NTB and Cu^IThe ions form a three-dimensional network structure, crystallographically orientedbThe axial direction exhibits two types of regular channels, among which, oxidized form [ W ]₆O₁₉]^2–The polyacid anions occupy one of the channels, and the other channel is at least used for carrying out the photocatalytic tandem reaction.

3. A method for the preparation of an optical functional composite according to claim 1 or 2, characterized in that it comprises:

mixing a mixture of 1: 5: 5-1: 5: 10, fully mixing polyoxometallate, copper salt and NTB ligand in a solvent, and then curing at 110-130 ℃ for 60-84 h to obtain orange blocky crystals, namely the optical functional composite material.

4. A method of preparing an optical functional composite according to claim 3, characterized in that: the copper salt is hydrated copper nitrate.

5. The method of claim 4 for the preparation of an optical functional composite, wherein: the copper salt is copper nitrate trihydrate.

6. A method of preparing an optical functional composite according to claim 3, characterized in that: the polyoxometallate is (TBA)₄[W₁₀O₃₂]。

7. A method of preparing an optical functional composite according to claim 3, characterized in that: the solvent is selected from DMF and/or water.

8. The light function of claim 3The preparation method of the composite material is characterized by comprising the following steps: uniformly mixing a copper salt, an NTB ligand and polyoxometallate to obtain a mixture, and adding the mixture into a solvent, wherein the dosage ratio of the mixture to the solvent is 60 mg: 2 mL-90 mg: 5mL, 1-2 mol. L^–1The pH value of the HCl adjusting system is 2.5-3.0, the HCl adjusting system is stirred for 20-40 min at normal temperature, and after the HCl adjusting system is fully mixed, curing treatment is carried out.

9. The use of the optical functional composite material of claim 1 or 2 in the preparation of sulfoxides by photocatalytic decomposition of water or tandem photocatalytic decomposition of water to produce oxygen and selective oxidation of thioethers.

10. A photocatalytic decomposition water oxygen generation catalyst, characterized by comprising the optical functional composite material of claim 1 or 2.

11. A method for producing oxygen by photocatalytic decomposition of water is characterized by comprising the following steps: use of the optical functional composite material of claim 1 or 2 as a catalyst, sodium persulfate as an electron acceptor, [ Ru (bpy) ]₃]Cl₂As a photosensitizer, visible light is used as a light source, and water is subjected to photocatalytic decomposition in a boric acid buffer system to obtain oxygen.

12. A catalyst for the tandem photocatalytic decomposition of water to produce oxygen and the selective synthesis of sulfoxide, characterized by comprising the optical functional composite material of claim 1 or 2.

13. A method for producing oxygen by serial photocatalytic water decomposition and selectively synthesizing sulfoxide is characterized by comprising the following steps: the optical functional composite material of claim 1 or 2 as a catalyst, aryl sulfide as a reaction substrate, sodium persulfate as an electron acceptor, [ Ru (bpy) ]₃]Cl₂As a photosensitizer, visible light is used as a light source, and a series photocatalytic reaction is carried out in a boric acid buffer system.

Images