Synthesis and application of a new type of viologen containing chalcogenide

Abstract

The application discloses a novel sulfur-containing group element viologen cyclotriphosphazene and an application thereof, expands a conjugate environment of the sulfur-containing group element viologen, and the compound has the following properties: 1, a more stable free radical state; 2, a narrower band gap width and stronger visible light absorption; 3, a low reduction potential and a low LUMO energy level; 4, stronger absorption in the visible light range; 5, better redox performance and efficient photocatalytic directional electron flow. The application provides a synthesis method of the novel sulfur-containing group element viologen cyclotriphosphazene, and the method can extend to multiple types of cyclotriphosphazenes. The cyclotriphosphazenes have multiple functions and can be applied to multiple fields. The application provides application schemes of the novel sulfur-containing group element viologen cyclotriphosphazene in multiple application fields such as a photocatalytic hydrogen production field, an electrochromic field and a photochromic field.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of photocatalytic hydrogen production, the field of electrochromism and the field of photochromism, and the present application mainly relates to a new type of sulfur-containing element-containing viologen ring and a synthesis method thereof and application thereof in photocatalytic hydrogen production, electrochromism and photochromism. BACKGROUND

[0002] As a new type of macrocyclic host, cationic viologen ring is widely used in host-guest chemistry, mechanically interlocked molecules, luminescent materials, drug delivery, molecular catalysis and other fields due to its rigid cavity, excellent electron-deficient characteristics, good redox performance and other advantages. In particular, the Blue Box developed by Stoddart and his colleagues in the past 35 years has shown excellent application in supramolecular structures, host-guest complexes, catalysis and mechanically interlocked molecules. However, this type of viologen ring has defects such as rotatable benzene ring and low electron cloud density in structure, which leads to the disadvantages of almost no absorption of visible light, low luminescent efficiency and slow electron transfer rate, which greatly limits its development and application in multiple application fields such as photocatalytic hydrogen production, electrochromism and photochromism.

[0003] Current technologies can bridge main group elements (such as P, S, Se, Te and Bi) on the bipyridine group of small molecules, and can improve their photoelectric performance and the stability of cationic radicals. This design essentially solves the low conjugation degree of viologen molecules, which can significantly reduce the energy gap of viologen derivatives. At the same time, the electronic energy level and structure of the system are changed to some extent, which will significantly affect the properties of the molecule, such as changing the position of the LUMO level, changing the size of the reduction potential, changing the color of different redox states of viologen, etc. Based on the above considerations, from a theoretical point of view, combining main group elements with viologen rings can make viologen rings have more rigid electron-deficient cavities, higher electron cloud density, narrower band gap, better visible light absorption and better redox performance. Whether it can be realized in practice needs to be verified.

[0004] In addition, in the photocatalytic hydrogen production system, viologen can exhibit three states (MV 2+ , MV +·MV) with excellent redox reversibility, which is often used as an electron transfer mediator. When the main group elements mentioned above, especially the chalcogen elements, are introduced, they can simultaneously act as photosensitizers and electron transfer mediators, significantly improving the efficiency of photocatalytic hydrogen production. Some researchers have also developed systems with photosensitizers, electron transfer mediators, and catalysts, but the relatively long and freely rotating linkers between units limit the electron flow process. How to control the distance and spatial position between units through structure is a necessary condition for more effective and precise electron flow control.

[0005] The defects of rotatable benzene ring and low electron cloud density in the structure of viologen lead to almost no absorption of visible light, low luminescence efficiency, and slow electron transport rate, which affects its development and application in the fields of photocatalytic hydrogen production, electrochromic, and photochromic. The existing photocatalytic hydrogen production system has relatively long and freely rotating linkers between units, which limits the electron flow process. How to control the distance and spatial position between units through structure is a necessary condition for more effective and precise electron flow control. SUMMARY

[0006] In view of the defects of rotatable benzene ring and low electron cloud density in the structure of viologen, which lead to almost no absorption of visible light, low luminescence efficiency, and slow electron transport rate, and affect its development and application in the fields of photocatalytic hydrogen production, electrochromic, and photochromic, the existing photocatalytic hydrogen production system has relatively long and freely rotating linkers between units, which limits the electron flow process. The purpose of the present application is to provide a new type of chalcogen-containing viologen; the second purpose of the present application is to provide a new type of chalcogen-containing viologen complex; the third purpose of the present application is to provide a synthesis method of the new type of chalcogen-containing viologen; and the fourth purpose of the present application is to provide applications of the new type of chalcogen-containing viologen and its complex in electrochromic device preparation, photochromic device preparation, and photocatalytic hydrogen production system.

[0007] In order to achieve the above purposes, the technical scheme adopted by the present application is as follows:

[0008] A chalcogen-containing viologen, the structural formula of which is as follows:

[0009]

[0010] Among them, R1 is and Any one of them; E is any one of chalcogen elements S, Se, and Te.

[0011] A chalcogen-containing viologen complex, the structural formula of which is as follows:

[0012]

[0013] wherein R2 is Any one; E is any one of sulfur family elements S, Se, Te; M is any one of Pt, Re, Ru, L is the corresponding ligand of M, and n is the number of the corresponding ligand of M.

[0014] The application provides a synthesis method of a sulfur family element-containing viologen ring, and the specific steps are as follows:

[0015] S1: the sulfur family element-containing viologen and compound 2 are mixed in a solvent, heated to reflux, precipitated by adding excess NH4PF6, centrifuged and washed to obtain a sulfur family element-containing viologen half ring;

[0016] S2: the sulfur family element-containing viologen half ring obtained in step S1 is dissolved by being heated in a solvent, then compound 4 dispersed in a solvent is added, the precipitate is collected after the reaction and cooling to room temperature, centrifuged and washed, dispersed in water, precipitated by adding excess NH4PF6, centrifuged and washed, and column chromatography is used to purify to obtain a sulfur family element-containing viologen ring, and the specific reaction process is as follows:

[0017]

[0018] wherein compound 2 is Any one; compound 4 is the sulfur family element-containing viologen is E is any one of sulfur family elements S, Se, Te;

[0019] In step S1, the molar ratio of the sulfur family element-containing viologen and compound 2 is 5-15:1, the reaction temperature is 80-110 DEG C, the reaction time is 2-4 days, and the solvent is acetonitrile.

[0020] In step S2, the molar ratio of the sulfur family element-containing viologen half ring and compound 4 is 1-2:1-3, the reaction temperature is 100-120 DEG C, the reaction time is 2-4 days, and the solvent is acetonitrile; column chromatography uses a mixed solution of saturated ammonium hexafluorophosphate acetonitrile solution and dichloromethane with a volume ratio of 1:1-20 as a mobile phase.

[0021] Meanwhile, a synthesis method of a sulfur family element-containing viologen ring complex is provided, wherein a new sulfur family element-containing viologen ring and compound 6 are added into methanol, heated to 70-90 DEG C and reacted for 2-4 days, the precipitate is collected after cooling to 0 DEG C, and the precipitate is washed by centrifugation to obtain a sulfur family element-containing viologen ring complex.

[0022] wherein compound 6 is Any one of the above.

[0023] The molar ratio of the sulfur-containing group element viologen cyclavan to compound 6 is 1-2:1-3, the reaction temperature is 70-90 DEG C, the reaction time is 2-4 days, and the solvent is methanol.

[0024] Meanwhile, the application provides application of the above-mentioned sulfur-containing group element viologen cyclavan in an electrochromic device.

[0025] Application of the above-mentioned sulfur-containing group element viologen cyclavan or complex in an electrochromic device.

[0026] Application of the above-mentioned sulfur-containing group element viologen cyclavan in a photochromic device.

[0027] Application of the above-mentioned sulfur-containing group element viologen cyclavan complex in an electrochromic device.

[0028] Application of the above-mentioned sulfur-containing group element viologen cyclavan complex in a photochromic device.

[0029] Application of the above-mentioned sulfur-containing group element viologen cyclavan complex in a photocatalytic hydrogen production system.

[0030] Compared with the prior art, the application has the following beneficial effects:

[0031] The application combines main group elements with viologen cyclavan, controls the distance and spatial position between structural units, realizes more effective and accurate electron flow control, expands the conjugated environment of the sulfur-containing group element viologen, and obtains a new type of sulfur-containing group element viologen cyclavan and complex, which has the following properties: 1. more stable free radical state; 2. narrower band gap width and stronger visible light absorption; 3. low reduction potential and low LUMO level; 4. stronger absorption in the visible light range; 5. better redox performance and efficient photocatalytic directional electron flow. The defects of the viologen cyclavan, such as almost no absorption of visible light, low light-emitting efficiency and slow electron transmission rate, caused by the rotatable benzene ring in the structure and the low electron cloud density, are overcome, and therefore, the viologen cyclavan can be used in the field of electrochromic and photochromic devices.

[0032] The new type of sulfur-containing group element viologen cyclavan complex provided by the application has stronger absorption in the visible light range, is used as a photosensitizer, an electron transfer medium and a catalyst, has high light-emitting efficiency and high electron transmission speed, is applied to a photocatalytic hydrogen production system, has a hydrogen production amount of 132.0 micromoles after xenon lamp irradiation for 12 hours, realizes high sensitivity of industrial hydrogen production only through light source control, has a remarkable cyclic hydrogen production effect under natural light irradiation, is more than 78% of the previous cycle, can be repeatedly used, indicates that the new type of sulfur-containing group element viologen cyclavan complex can be used to catalytically produce hydrogen by using solar energy, and verifies the feasibility of hydrogen production by using solar energy. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1The application provides a schematic diagram of a sulfur group element-containing viologen cyclavan.

[0034] Figure 2 The application provides a schematic diagram of a sulfur group element-containing viologen cyclavan.

[0035] Figure 3 The application provides a schematic diagram of a sulfur group element-containing viologen cyclavan.

[0036] Figure 4 The application provides a schematic diagram of a sulfur group element-containing viologen cyclavan.

[0037] Figure 5 The application provides a schematic diagram of a sulfur group element-containing viologen cyclavan.

[0038] Figure 6 The application provides a schematic diagram of a sulfur group element-containing viologen cyclavan.

[0039] Figure 7 The application provides a schematic diagram of a sulfur group element-containing viologen cyclavan.

[0040] Figure 8 The application provides a schematic diagram of a sulfur group element-containing viologen cyclavan. DETAILED DESCRIPTION

[0041] In the following, the technical solutions in the embodiments of the present application will be described clearly and completely with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by a person of ordinary skill in the art without creative effort should fall within the protection scope of the present application.

[0042] It should be noted that the terms "first", "second", and the like in the specification and claims of the present application and the above-described drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or a chronological sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product, or device including a series of steps or units does not necessarily have to be limited to only those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to the process, method, product, or device.

[0043] The present application will be described in further detail below with reference to the drawings:

[0044] A synthesis method of a new type of sulfur-containing element viologen ring, the specific steps are as follows:

[0045] S1: add sulfur-containing element viologen and compound 2 into a solvent to mix, heat to reflux to react, then add excess NH4PF6 to precipitate, centrifugal wash to obtain a sulfur-containing element viologen half ring;

[0046] S2: after the sulfur-containing element viologen half ring obtained in step S1 is dissolved by heating in a solvent, compound 4 dispersed in a solvent is added to react, after the reaction, the precipitate is collected after cooling to room temperature, centrifugal wash, then dispersed in water, excess NH4PF6 is added to precipitate, centrifugal wash, and column chromatography purification is performed to obtain a sulfur-containing element viologen ring;

[0047] wherein, compound 2 is any one; compound 4 is sulfur-containing element viologen is E is any one of sulfur element S, Se, and Te;

[0048] In the step S1, the molar ratio of the sulfur-containing element viologen and compound 2 is 5-15:1, the reaction temperature is 80-110°C, and the reaction time is 2-4 days, and the solvent is acetonitrile.

[0049] The molar ratio of the sulfur-containing element-containing viologen half-ring to compound 4 in the step S2 is 1-2:1-3, the reaction temperature is 100-120 DEG C, the reaction time is 2-4 days, and the solvent is acetonitrile; the column chromatography adopts a mixed solution of acetonitrile and dichloromethane with a volume ratio of 1:1-20 as the mobile phase.

[0050] Example 1: Preparation of sulfur-containing element-containing viologen cyclophanes

[0051] The sulfur-containing element-containing viologen cyclophanes prepared by the method of the present application can be prepared by the following reaction equation steps:

[0052] 1) Preparation of sulfur-containing element-containing viologen half-ring 3

[0053]

[0054] Compound 1 (7 mmol) and super-dry acetonitrile (100 mL) were added into a three-necked flask, a condensation reflux device was installed, the temperature was raised to the reflux temperature, and all the compounds were dissolved. Compound 2 (700 μmol) was dispersed in super-dry acetonitrile (20 mL), and was slowly added into the reaction in multiple times, and was heated to reflux for 3 days. Then the mixture was cooled to room temperature, the precipitate was collected, washed with acetonitrile (20 mL) by centrifugation, and repeated three times to obtain a solid crude product. The crude product was dispersed in 5 mL of water, an excess amount of NH4PF6 was added, and stirred for 12 h. The precipitate was collected and washed with water (10 mL) by centrifugation, and repeated three times to obtain a solid crude product of the sulfur-containing element-containing viologen half-ring 3 with hexafluorophosphate as an anion, and E is any one of the sulfur-containing elements S, Se, and Te.

[0055] 2) Preparation of sulfur-containing element-containing viologen cyclophanes 5

[0056]

[0057] Compound 3 (200 μmol) and tetrabutylammonium iodide (TBAI, 40 μmol) were placed in a single-necked pressure bottle. Ultra-dry acetonitrile (180 mL) was added and the temperature was raised to 90°C to dissolve all the compounds. Compound 4 (200 μmol) was dispersed in ultra-dry acetonitrile (20 mL) and slowly added to the reaction mixture in multiple portions. The mixture was sealed and heated to 110°C for 3 days. The mixture was then cooled to room temperature, and the precipitate was collected and washed by centrifugation with acetone (10 mL). This was repeated three times to obtain a crude yellow solid. The crude product was dispersed in 3 mL of H₂O, and an excess of NH₄PF₆ was added and stirred for 12 h. The precipitate was collected and washed with water (5 mL) to obtain a crude solid containing hexafluorophosphate anions. The crude product was purified by column chromatography using a mixture of saturated ammonium hexafluorophosphate in acetonitrile and dichloromethane as the mobile phase to obtain a solid product, viologen cyclophane 5, where E is any of the chalcogen elements S, Se, or Te.

[0058] Example 2: Preparation of Viologen Cyclophane Containing Sulfur Elements

[0059] 1) Preparation of Chalcogen-Containing Viologen Semicycle 8

[0060]

[0061] Compound 1 (7 mmol) and ultra-dry acetonitrile (100 mL) were added to a three-necked flask, a condensing reflux apparatus was installed, and the temperature was raised to reflux temperature to dissolve all the compounds. Compound 4 (7 μmol) was dispersed in ultra-dry acetonitrile (20 mL), slowly added to the reaction in several portions, and heated under reflux for 3 days. The mixture was then cooled to room temperature, the precipitate was collected, and the mixture was centrifuged and washed with acetonitrile (20 mL) three times to obtain a solid crude product. The crude product was dispersed in 5 mL of water, an excess of NH4PF6 was added, and the mixture was stirred for 12 h. The precipitate was collected and centrifuged and washed with water (10 mL) three times to obtain a solid crude product containing a sulfide element viologen hemicycle 8 with hexafluorophosphate as an anion.

[0062] 2) Preparation of Sulfur-containing Viologen Cyclofan 9

[0063]

[0064] Compound 8 (200 μmol) and tetrabutylammonium iodide (TBAI, 40 μmol) were added to a single-neck pressure bottle, and super-dry acetonitrile (180 mL) was added, and the temperature was raised to 90°C to dissolve all the compounds. Compound 4 (200 μmol) was dispersed in super-dry acetonitrile (20 mL), and was slowly added to the reaction in multiple portions, sealed, and the temperature was raised to 110°C for 3 days. Then the mixture was cooled to room temperature, and the precipitate was collected and washed with acetone (10 mL) three times to obtain a yellow solid as a crude product. The crude product obtained above was dispersed in 3 mL of H2O, and an excess of NH4PF6 was added and stirred for 12 h. The precipitate was collected and washed with water (5 mL) to obtain a solid crude product containing hexafluorophosphate anions. The crude product was purified by column chromatography using a mixture of saturated ammonium hexafluorophosphate in acetonitrile and dichloromethane as the mobile phase to obtain a solid product of chalcogen-containing viologen calix-bowl 9, E being any one of the chalcogens S, Se, Te.

[0065] Example 3: Preparation of chalcogen-containing viologen calix-bowl complex

[0066] This example is based on Example 1, and a Pt-coordinated chalcogen-containing viologen calix-bowl 7 is prepared, and the specific reaction formula is as follows:

[0067]

[0068] Compound 5 (20 μmol) and compound 6 (20 μmol) were added to a single-neck pressure bottle, super-dry methanol (2 mL) was added, sealed, and the temperature was raised to 80°C for 3 days. Then the mixture was cooled to 0°C, the precipitate was collected and washed with methanol 5 mL, and a solid product of Pt-coordinated chalcogen-containing viologen calix-bowl 7 was obtained, E being any one of the chalcogens S, Se, Te, containing hexafluorophosphate anions.

[0069] Example 4: Preparation of chalcogen-containing viologen calix-bowl complex

[0070] This example is based on Example 2, and a Pt-coordinated chalcogen-containing viologen calix-bowl 10 is prepared, and the specific reaction formula is as follows:

[0071]

[0072] Compound 9 (20 μmol) and compound 6 (40 μmol) were added to a single-neck pressure bottle, super-dry methanol (2 mL) was added, sealed, and the temperature was raised to 80°C for 3 days. Then the mixture was cooled to 0°C, the precipitate was collected and washed with methanol 5 mL, and a solid product of Pt-coordinated chalcogen-containing viologen calix-bowl 10 was obtained, E being any one of the chalcogens S, Se, Te, containing hexafluorophosphate anions.

[0073] Example 5: Structural characterization of sulfur group-containing viologen cyclophanes and their complexes

[0074] Some basic characterizations of the above-prepared sulfur group-containing viologen cyclophanes and their complexes of the present application are as follows:

[0075] Sulfur group-containing viologen half-cyclophanes 3, E = Se, 1 H NMR (400 MHz, CD3CN) δ 9.51 (s, 2H), 9.46 (s, 2H), 8.92 - 8.79 (m, 6H), 8.44 (d, J = 4.8 Hz, 2H), 7.79 (d, J = 8.0 Hz, 4H), 7.60 (d, J = 8.0 Hz, 4H), 5.89 (s, 4H). 13 C NMR (151 MHz, CD3CN) δ 150.80, 149.86, 146.92, 144.74, 142.15, 141.81, 141.43, 140.92, 140.09, 133.66, 131.12, 129.04, 123.42, 121.01, 65.38. HRMS (ESI + )m / z: [M - 2PF6] 2+ calcd for C 34 H 24 N4Se2 2+ 324.01602, found 324.01553; Mp (°C): 195 °C.

[0076] Sulfur group-containing viologen cyclophanes 5, E = Se, 1 H NMR (400 MHz, CD3CN) δ 9.42 (s, 2H), 9.38 (s, 2H), 9.13 - 9.06 (m, 4H), 8.92 - 8.87 (m, 4H), 8.82 (d, J = 2.3 Hz, 2H), 8.41 (d, J = 8.0 Hz, 2H), 8.08 (dd, J = 8.0, 2.0 Hz, 2H), 7.67 (d, J = 8.4 Hz, 4H), 7.57 (d, J = 8.4 Hz, 4H), 6.00 (s, 4H), 5.94 (s, 4H). 13 C NMR (151 MHz, CD3CN) δ 157.19, 151.04, 147.35, 147.18, 145.39 - 144.90 (m), 144.72, 141.60, 141.16, 141.04, 139.60, 134.78, 131.46, 131.02, 128.86, 126.10, 125.91, 122.42, 66.59, 64.11. HRMS (ESI +m / z: [M-4PF6] 4+ calcd for C 46 H 34 N6Se2 4+ 207.5291, found 207.5311; [M-3PF6] 3+ calcd for C 46 H 34 F6N6PSe2 3+ 325.0271, found 325.0255; [M-2PF6] 2+ calcd for C 46 H 34 F 12 N6P2Se2 2+ 560.0229, found 560.0212; [M-PF6] + calcd for C 46 H 34 F 18 N6P3Se2 + 1265.0106, found 1265.0112; Mp (°C): 277 °C.

[0077] Pt-coordinated chalcogen-containing viologen cryptand 7, E = Se, 1 H NMR (400 MHz, CD3CN) δ 9.60 (s, 2H), 9.45 - 9.40 (m, 4H), 9.10 (d, J = 6.4 Hz, 4H), 8.97 - 8.90 (m, 4H), 8.51 (d, J = 8.8 Hz, 2H), 8.24 (d, J = 8.4 Hz, 2H), 7.68 (d, J = 8.4 Hz, 4H), 7.58 (d, J = 8.0 Hz, 4H), 6.13 (s, 4H), 5.95 (s, 4H). 13 C NMR (151 MHz, DMF-d7) δ 157.92, 150.06, 147.20, 146.85, 146.70, 146.24, 145.58, 145.24, 142.45, 141.29, 140.54, 135.84 (d, J = 7.4 Hz), 130.67, 128.46, 128.05, 125.93 - 125.47 (m), 65.70, 62.28. HRMS (ESI + m / z: [M-3PF6] 3+ calcd for C 46 H 34 F6N6PSe2PtCl2 3+412.9944, found 412.9949; [M-2PF6] 2+ calcd for C 46 H 34 F 12 N6P2Se2PtCl2 2+ 691.9740, found 691.9840; Mp (°C): >300 °C.

[0078] Example 6: Application of chalcogen-containing viologen cyclodextrin

[0079] Based on the above-synthesized chalcogen-containing viologen cyclodextrin, the application performance of the novel chalcogen-containing viologen cyclodextrin and its complex provided in Example 1 and Example 3 of the present application is tested, and the application field is shown in the following table: Figure 1 The device assembly and expansion of the application examples are as follows:

[0080] 1. Electrochromic device based on chalcogen-containing viologen cyclodextrin

[0081] An electrochromic device is prepared using the above product. Two pieces of conductive glass (such as ITO glass, FTO glass, or any transparent device that can conduct electricity, and FTO glass is used as an example in the present application) are attached together with double-sided tape to form a device substrate with a 50 μm thick cavity (the outer side retains a portion of the conductive area), and the chalcogen-containing viologen cyclodextrin or its complex in Example 1 and Example 3 is dissolved in N,N-dimethylformamide, then added to the cavity of the above-prepared device substrate, and the sealing area is sealed to obtain a simple electrochromic device. Various specific shape electrochromic devices can also be prepared according to the shape and position of the conductive layer, the filling position of the solution, or the switching of the voltage, including but not limited to smart color-changing doors and windows, electronic price tags, and pixel point electrochromic displays, etc.

[0082] 2. Photochromic device based on chalcogen-containing viologen cyclodextrin

[0083] A photochromic device is prepared using the above product. Two pieces of ordinary glass are attached together with double-sided tape to form a device substrate with a 50 μm thick cavity, and the chalcogen-containing viologen cyclodextrin or its complex in Example 1 and Example 3 above is dissolved in N,N-dimethylformamide together with a substance that can provide electrons such as triethanolamine, then added to the cavity of the above-prepared device substrate, and sealed to obtain a simple photochromic device. Specific shape photochromic devices can also be prepared, and this method is only an example of device preparation, and any light-transmitting container that can store a solution can be used as a photochromic device container. Other devices with the same principle can be made based on this. For convenience of testing data characterization, a glass bottle for testing ultraviolet is directly used as a container in the present application, and the corresponding solution is added as a simple electrochromic device.

[0084] 3. A photocatalytic hydrogen production device based on chalcogen-containing viologen cyclodextrin, mainly chalcogen-containing viologen cyclodextrin having coordinated Pt

[0085] The above coordination product is dispersed in water together with a sacrificial agent ethylenediamine tetramethylene phosphonic acid, and sealed with a light-transmitting glass to prepare a simple photocatalytic hydrogen production device. Hydrogen can be produced by irradiation with visible light during stirring. When the irradiation is stopped, the production of hydrogen stops rapidly, so that in this type of device, the production of hydrogen can be controlled only by controlling the on-off of the light source or by setting a blocking device for the irradiation of the light source, without the need for other complicated on-off control, which is conducive to their application.

[0086] The test results are shown in Figures 2-8 :

[0087] Figure 2 The cyclic voltammograms and differential pulse voltammograms of the viologen cyclodextrin 5 (E = Se) with tetrabutylammonium hexafluorophosphate as the supporting electrolyte and DMF as the solvent at different scan rates are shown in Figure 2 A and 2B, which shows that the viologen cyclodextrin exhibits two reversible redox processes, and each redox process involves two electron reductions, with the reduction peak potentials being -1.32 V and -0.89 V, respectively.

[0088] Figure 3 The cyclic voltammograms and differential pulse voltammograms of the viologen cyclodextrin complex 7 (E = Se) with tetrabutylammonium hexafluorophosphate as the supporting electrolyte and DMF as the solvent at different scan rates are shown in Figure 3 A and 3B, which shows that the viologen cyclodextrin complex exhibits two reversible redox processes, and each redox process involves two electron reductions, with the reduction peak potentials being -1.25 V and -0.83 V, respectively.

[0089] Figure 4 The color change and ultraviolet-visible absorption spectrum change of the viologen cyclodextrin 5 (E = Se) during electrochromic process under different applied voltages are shown in Figure 4 A, which shows that when the external voltage is raised from 0 to 3.2 V, the color of the viologen cyclodextrin 5 changes from yellow to green, and when the external voltage is raised to 4.5 V, the color changes to brown. Further testing of the ultraviolet-visible absorption spectrum under different applied voltages shows that Figure 4Data B and 4C show that when the applied voltage is 3.2 V, new absorption peaks appear at around 650 nm and 720 nm for viologen cyclofan 5, and the absorption peak at around 390 nm increases; when the applied potential is increased to 4.5 V, the absorption peak at around 390 nm of viologen cyclofan 5 further increases, while the absorption peaks at around 650 nm and 720 nm gradually decrease, which corresponds to the above-mentioned color change, indicating that the viologen cyclofan of the present invention can be used in the preparation of electrochromic devices.

[0090] Figure 5 The color change and UV-visible absorption spectrum of viologen cyclophane complex 7 (E=Se) during the electrochromic process under different applied voltages are shown. Figure 5 A shows that when the external voltage increases from 0 to 2.8V, its color changes from yellow to green; when the external voltage increases to 3.6V, its color changes to dark yellow; further testing of its UV-visible absorption spectrum with different voltages shows that the UV-visible absorption spectrum is Figure 5 From the data of Figures B and 5C, it can be seen that when the applied voltage is 2.8 V, a new absorption peak appears at around 650 nm for viologen-cyclophane complex 7, and the absorption peak at around 390 nm increases; when the applied potential is increased to 3.6 V, the absorption peak of viologen-cyclophane complex 7 at around 390 nm further increases, while the absorption peak at around 650 nm gradually decreases, which corresponds to the above-mentioned color change, indicating that the viologen-cyclophane complex of the present invention can be used for the preparation of electrochromic devices.

[0091] Figure 6 The color change and UV-visible absorption spectrum of viologen cyclophane 5 (E = Se) and viologen cyclophane complex 7 (E = Se) during the photochromic process, where triethylamine is used as an electron donor. Figure 6 Data A shows that with the increase of irradiation time, the absorption peaks of the UV-visible absorption spectrum of viologen cyclofan 5 at around 650nm and 720nm gradually increase and remain stable after 90s, at which time the color changes from yellow to green; Figure 6 Data B shows that with the increase of irradiation time, the absorption peak of the ultraviolet-visible absorption spectrum of viologen cyclophane complex 7 at around 650nm gradually increases and remains stable after 120s, at which time the color changes from yellow to green, indicating that the viologen cyclophane and the complex of the present invention can be used in the preparation of photochromic devices. At the same time, they all absorb visible light, indicating that the novel sulfur-containing viologen cyclophane and the complex provided by the present invention overcome the problem that viologen cyclophane has almost no absorption of visible light due to the defects of the structure of the rotatable benzene ring and the low electron cloud density, thereby providing a possibility for its application in photocatalytic systems.

[0092] Figure 7The hydrogen production curve of the viologen macrocycle complex 7 (E=Se) under visible light irradiation over time and the hydrogen production curve under visible light irradiation and off are shown in the following A and B figures. Figure 7 According to the data in A, after the xenon lamp irradiation for 12 hours, the hydrogen production is 132.0 μmol, the turnover number is 221.1, and the apparent quantum yield is 1.74%. Figure 7 According to the data in B, when the xenon lamp is used for irradiation, hydrogen can be continuously and stably produced, and when the light source is turned off, almost no hydrogen is produced, which shows that the viologen macrocycle complex containing sulfur element provided by the present application can absorb visible light, and as a photosensitizer, electron transfer medium and catalyst, has high light emission efficiency and high electron transfer speed, and overcomes the problems of almost no absorption of visible light, low light emission efficiency and slow electron transfer speed of the viologen macrocycle due to the defects of rotatable benzene ring and low electron cloud density in the structure, and can be applied to a photocatalytic system, and also shows the necessity of the light source for the photocatalytic system, and the sensitivity of hydrogen production can be controlled by controlling the light source, which provides a simple and effective solution for controlling the activation and deactivation of hydrogen production in industrial production.

[0093] Figure 8 The hydrogen production repeatability cycle test of the viologen macrocycle complex 7 (E=Se) under visible light irradiation and the hydrogen production effect under natural light without stirring are shown in the following A and B figures. Figure 8 According to the data in A, the hydrogen production effects of each cycle are 79.9%, 86.6% and 78.1% of the previous cycle, respectively, which shows that the viologen macrocycle complex can be reused to a certain extent. Figure 8 According to the data in B, the photocatalytic hydrogen production test under natural light shows that the viologen macrocycle complex provided by the present application can be used to catalyze hydrogen production by using solar energy, and the feasibility of hydrogen production by using solar energy is verified.

[0094] The above content only illustrates the technical idea of the present application, and cannot limit the protection scope of the present application, and any modification made according to the technical idea of the present application on the basis of the technical solution falls within the protection scope of the claims of the present application.

Claims

1. A type of sulfur-containing viologen cyclophane, characterized in that: The structural formula is as follows: Among them, R1 is Any one of E is any one of the chalcogen elements S, Se, Te, and X is 4PF6 - .

2. A sulfide-containing viologen-cyclophane complex prepared from the sulfide-containing viologen-cyclophane according to claim 1, characterized in that: The structural formula is as follows: Among them, R2 is Any one; E is any one of the chalcogen elements S, Se, and Te; M is Pt, L is the corresponding ligand of M, Cl, and n is the number of the corresponding ligands of M, and n is 2.

3. A method for synthesizing the sulfide-containing viologen cyclophane according to claim 1, characterized in that: The specific steps are as follows: S1: adding the sulfide-containing viologen and compound 2 to a solvent, mixing, heating under reflux, adding excess NH4PF6 for precipitation, and centrifuging and washing to obtain the sulfide-containing viologen half ring; S2: dissolving the sulfide-containing viologen hemicycle obtained in step S1 and tetrabutylammonium iodide in a solvent at elevated temperature, adding the solvent-dispersed compound 4 to react, cooling to room temperature after the reaction, collecting the precipitate, washing it by centrifugation, and dispersing it in water. Adding excess NH4PF6 to the precipitate, washing it by centrifugation, and purifying it by column chromatography to obtain the sulfide-containing viologen cyclophane; Among them, compound 2 is Compound 4 is Viologen containing sulfur elements is E is any one of the chalcogen elements S, Se, and Te.

4. The method for synthesizing the sulfide-containing viologen cyclophane according to claim 3, wherein: In the step S1, the molar ratio of the chalcogen-containing viologen to the compound 2 is 5-15:1, the reaction temperature is 80-110° C., the reaction time is 2-4 days, and the solvent is acetonitrile.

5. The method for synthesizing the sulfide-containing viologen cyclophane according to claim 3, wherein: In step S2, the molar ratio of the chalcogen-containing viologen half ring to compound 4 is 1-2:1-3, the reaction temperature is 100-120° C., the reaction time is 2-4 d, and the solvent is acetonitrile; the column chromatography uses a mixed solution of saturated ammonium hexafluorophosphate in acetonitrile and dichloromethane in a volume ratio of 1:1-20 as the mobile phase.

6. A method for synthesizing the sulfide-containing viologen-cyclophane complex according to claim 2, characterized in that: The sulfide-containing viologen cyclophane and compound 6 were added to a solvent and mixed, heated for reaction, cooled to 0°C, and the precipitate was collected and washed by centrifugation with methanol to obtain the sulfide-containing viologen cyclophane complex; Among them, compound 6 is 7. The method for synthesizing the sulfide-containing viologen-cyclophane complex according to claim 6, wherein: The molar ratio of the chalcogen-containing viologen cyclophane to compound 6 is 1-2:1-3, the reaction temperature is 70-90° C., the reaction time is 2-4 days, and the solvent is methanol.

8. Use of the chalcogen-containing viologen cyclophane according to claim 1 in electrochromic / photochromic devices.

9. Use of the chalcogen-containing viologen-cyclophane complex according to claim 2 in electrochromic / photochromic devices.

10. Use of the sulfide-containing viologen-cyclophane complex according to claim 2 in a photocatalytic hydrogen production system.

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