Magnetic field and photocatalysis combined device and method

Abstract

The invention discloses a magnetic field and photocatalysis combined device and method. The device comprises a magnetic field generation module, a reaction module, a light intensity monitoring module and a light source switching module, the magnetic field control module comprises a Helmholtz coil for generating a magnetic field and an electromagnet; the Helmholtz coil comprises two coils, the electromagnet comprises two pole heads, reaction modules and light intensity monitoring modules are arranged between the two coils and between the two pole heads, and each reaction module comprises a catalytic reactor; each light intensity monitoring module comprises an incident light side light intensity monitoring module and an emergent light side light intensity monitoring module which are respectively positioned on two sides of the catalytic reactor; and the laser emitting position in the light source switching module is adjustable, so that the emitted laser is emitted into the light intensity monitoring module between the two coils or the light intensity monitoring module between the two pole heads. The magnetic field can be adjusted from 0, and manual intervention for magnetic field adjustment is not needed in the catalytic reaction period.

Description

Technical Field

[0001] The invention belongs to the technical field of magnetic field-controlled photocatalysis, and in particular relates to a device and method for combining magnetic field and photocatalysis. Background Art

[0002] Organic photosynthesis has the characteristics of environmental friendliness, low energy consumption, and high atom economy. With the development of ruthenium and iridium metal complexes, organic dyes, and semiconductor material photocatalysts in recent years, visible light catalytic methodology has developed into one of the powerful synthetic methods in organic synthesis, promoting the rapid development of organic synthetic chemistry.

[0003] At present, the research on photocatalytic organic reactions focuses on the selectivity and yield of reactions, as well as the realization of some reaction types that cannot be achieved by thermal catalysis. There are few reports on the research and improvement of photoquantum efficiency. However, high quantum / energy efficiency is one of the necessary conditions for the industrial application of photocatalytic organic synthesis, which has great research significance and industrial value. However, the process of visible light catalysis is limited by the energy of visible light photons (i.e., 400-700nm, 1.8-3.1eV), and not all of this energy can be fully utilized. Intersystem crossing (ISC) and back electron transfer are important factors that limit the energy efficiency of photocatalytic organic reactions. Recently, the Nocera group at Harvard University used free radical binding to inhibit the electron back transfer of twin radical pairs, thereby improving the photoquantum yield. However, this method requires the introduction of additional chemical reagents, which is contrary to the green chemistry concept of 100% atomic utilization. Compared with light and electric fields, there are few reports on the regulation of organic catalytic reactions using static magnetic fields. Photocatalytic organic reactions often involve free radical pairs as intermediates, and magnetic fields can interact with free radical pairs, which provides a theoretical possibility for magnetic field regulation of photocatalytic organic reactions.

[0004] However, the existing equipment has the following deficiencies:

[0005] 1. There is no real-time monitoring of light intensity in the photocatalytic device, which makes it difficult to monitor the light utilization rate and quantum efficiency of the reaction process in real time, and the repeatability of mechanism and kinetic experiments is low.

[0006] 2. The magnetic field is not continuously adjustable from zero. The electromagnet still has residual magnetism after the power is removed. Experiments under zero magnetic field require other experimental conditions or experiments under residual magnetism conditions. Summary of the invention

[0007] In order to at least solve the problems existing in the prior art, the present invention provides a device and method for combining magnetic field and photocatalysis, which is a photocatalytic device coordinated with a continuously adjustable one-dimensional magnetic field. The device can monitor the changes in light intensity during the catalytic process in real time and can start the experiment from zero magnetic field.

[0008] In order to achieve the purpose of the present invention, the present invention provides a device for combining magnetic field and photocatalysis, including a magnetic field generating module, a reaction module, a light intensity monitoring module and a switching light source module.

[0009] The magnetic field generating module comprises a Helmholtz coil and an electromagnet, and the magnetic field axes of the Helmholtz coil and the electromagnet coincide with each other;

[0010] The Helmholtz coil includes two coils, the electromagnet includes two poles, a reaction module and a light intensity monitoring module are arranged between the two coils and between the two poles, each reaction module includes a catalytic reactor, and each light intensity monitoring module includes an incident light side light intensity monitoring module and an outgoing light side light intensity monitoring module respectively located on both sides of the catalytic reactor;

[0011] The laser emission position in the switching light source module is adjustable so that the emitted laser is emitted into the light intensity monitoring module between the two coils or the light intensity monitoring module between the two pole heads.

[0012] Furthermore, the magnetic field generating module also includes a power supply and a Hall probe. The Helmholtz coil and the electromagnet are both connected to the power supply. The power supply is used to provide the current required to generate the magnetic field. The Hall probe is arranged in the Helmholtz coil and the electromagnet.

[0013] Furthermore, the magnetic field strength generated by the Helmholtz coil after the power is turned on is 0-100mT; the magnetic field strength generated by the electromagnet after the power is turned on is 50-1000mT. The working principle of the Helmholtz coil is to generate a magnetic field when the power is turned on. When the power is turned off, it is only a copper coil, so there is no magnetic field when the power is turned off. The 0-100mT generated by the coil is the working magnetic field strength range provided by the manufacturer of the Helmholtz coil selected in the embodiment. The electromagnet includes a coil and an iron core. When the power is not turned on, there is residual magnetism in the iron core, and the pole head still has a magnetic field of about 50mT (measured value). The 50-1000mT generated by the electromagnet is the working magnetic field strength range provided by the electromagnet manufacturer.

[0014] Furthermore, the magnetic field generating modules are arranged on both sides of the outer wall of the reaction area, and the uniform magnetic field range is 1-50mm. (According to the empirical formula provided by the manufacturer and the finite element simulation results, the 1% magnetic field uniformity area is approximately the cylindrical area of ​​the electromagnet pole head diameter minus 1.1 times the gap)

[0015] Furthermore, the magnetic field generating module also includes a cooling device, and the cooling device is used to cool the Helmholtz coil and the electromagnet.

[0016] Furthermore, the cooling device is a water cooling device, which includes a water cooling flow path and a water chiller. The water cooling flow path and the water chiller are connected to form a loop, and the water cooling flow path flows through the Helmholtz coil and the electromagnet.

[0017] Furthermore, the switching light source module includes a linear guide rail and a laser end collimator slidably disposed on the linear guide rail. When working, the laser beam is emitted from the laser end collimator and incident on the light intensity monitoring module. By adjusting the position of the laser end collimator on the linear guide rail, the laser emitted by the light source can be adjusted to be incident on the light intensity monitoring module between the two coils or the light intensity monitoring module between the two pole heads.

[0018] Furthermore, the laser end collimator is provided in plurality, and the plurality of laser end collimators are fixed on a slider on the linear guide rail, and the position of the laser end collimator can be adjusted by moving the slider. The plurality of laser end collimators can provide lasers of different wavelengths, and light sources of different wavelengths can be automatically switched by cooperating with the linear guide rail.

[0019] Furthermore, the switching light source module can control the position of the laser end collimator and the laser power through a program.

[0020] Furthermore, there are multiple laser end collimators, the laser focal length is 150-350mm, and the multiple laser spots are controlled to be in the same plane through the slide rail adjustment. The laser spots of multiple planes with different focal lengths are adjusted to the same plane and fixed on the linear guide rail. When the slider in the subsequent linear guide rail is switched left and right, the laser spots can still be ensured to be in the same plane.

[0021] Furthermore, each of the reaction modules also includes a multi-channel valve, a vacuum pump, an inert gas mass flowmeter, at least one injection pump and a one-way valve, wherein the multi-channel valve includes an outlet and multiple inlet ports, wherein the outlet is connected to the catalytic reactor, and the multiple inlet ports are respectively connected to the injection pump, the vacuum pump, and the inert gas mass flowmeter through pipelines, and the injection pump, the vacuum pump, and the inert gas mass flowmeter are arranged at the rear end of the catalytic reactor. When working, emptying, purging, and switching different sample operations are performed by switching the different inlet ports. The multi-channel valve and the pump can realize the functions of automatic emptying, automatic switching, and sample replacement, which effectively ensures the consistency and repeatability of the experiment while improving the experimental efficiency.

[0022] Furthermore, the catalytic reactor is a cuvette reactor. Preferably, the cuvette reactor is any one of a common cuvette, a gas-tight cuvette with a stopcock, and a flow cuvette.

[0023] Furthermore, the optical path of the cuvette reactor is 1-20 mm.

[0024] Furthermore, the material of the cuvette reactor is any one of quartz, polymethyl methacrylate, and polystyrene.

[0025] Furthermore, the number of channels of the multi-channel valve is 3-10.

[0026] Furthermore, the material package of the multi-channel valve is any one of polytetrafluoroethylene, polyetheretherketone, and ceramic.

[0027] Furthermore, the number of injection pump channels is 1-8.

[0028] Furthermore, the injection pump is made of any one of quartz, polystyrene and polypropylene.

[0029] Furthermore, the vacuum pump is any one of a diaphragm pump, a piston pump, and an oil pump.

[0030] Furthermore, during operation, either the Helmholtz coil or the electromagnet is selectively used to generate a magnetic field.

[0031] Furthermore, the incident light side light intensity monitoring module includes a beam splitter prism, a first photodiode and a first signal collector. The beam splitter prism is arranged opposite to the switching light source module, the first photodiode is located above the beam splitter prism, and the first signal collector is connected to the first photodiode.

[0032] Furthermore, the light intensity monitoring module on the output light side includes a second photodiode and a second signal collector which are arranged in sequence, and the second photodiode is arranged close to the cuvette reactor.

[0033] Furthermore, the light intensity monitoring module is placed along the light path, the incident light monitoring module is placed behind the catalytic reactor, and the outgoing light monitoring module is placed behind the reactor.

[0034] The method for catalysis using the above device comprises the following steps:

[0035] The switching light source module is used to make the emitted laser light enter the light intensity monitoring module between the two coils or the light intensity monitoring module between the two pole heads;

[0036] The incident laser is divided into two beams of light by a beam splitter prism, defined as a first beam of light and a second beam of light. The first beam of light is finally projected onto the cuvette reactor, and after passing through the cuvette reactor, is projected onto the second photodiode of the output light detection module, and is converted into an electrical signal and collected by the second signal collector; the second beam of light is projected onto the first photodiode of the light intensity monitoring module on the incident light side by a beam splitter prism and is converted into an electrical signal and collected by the first signal collector.

[0037] Compared with the prior art, the present invention has at least the following beneficial effects:

[0038] 1. The present invention can monitor the light intensity of incident light and outgoing light in the photocatalytic process in real time, reduce the influence of light source instability on the experiment, and subsequently accurately calculate the quantum yield in the photocatalytic process according to the difference between the incident light and the outgoing light.

[0039] 2. In the prior art, when no current flows through the electromagnet, the pole head still has a residual magnetic field of about 50mT, which still interferes with the experiment. In the present invention, the Helmholtz coil can perform experiments of 0-100mT, and the electromagnet can perform experiments of 50mT-1000mT. The combination of the two can realize experiments with continuously adjustable magnetic fields of 0-1000mT. The present invention can start the experiment from zero magnetic field without moving the reactor, and can automatically switch the light source according to the experimental needs, reducing the optical path offset and experimental errors caused by human operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 A schematic diagram of the structure of a device combining magnetic field and photocatalysis provided in an embodiment of the present invention.

[0041] Figure 2 Schematic diagram of a reaction module and a light intensity monitoring module in an embodiment of the present invention.

[0042] Among them: 1-Helmholtz coil; 2-electromagnet; 3-reaction module and light intensity monitoring module; 4-laser end collimator; 5-linear guide; 6-colorimetric vessel reactor; 7-beam splitter prism; 8-incident light side light intensity detection module; 9-outgoing light side light intensity detection module, the supporting part is omitted in the figure.

[0043] Figure 3 Schematic diagram of the reaction module in the embodiment of the present invention, wherein: 10-injection pump; 11-inert gas mass flow controller; 12-vacuum pump; 13-multi-channel valve, the dotted line is the internal flow channel of the valve; 14-electronic vacuum pressure gauge; 15-check valve. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] See also Figure 1 The present invention provides a device for combining magnetic field and photocatalysis, which includes a magnetic field generating module, a switching light source module, a reaction module and a light intensity monitoring module.

[0046] The magnetic field generating module is arranged on both sides of the outer wall of the reaction area, and the magnetic field generating module includes a Helmholtz coil 1, an electromagnet 2, a cooling device, a linear power supply and a Hall probe; the Helmholtz coil 1 and the electromagnet 2 are placed axially, and the magnetic field axis centers of the Helmholtz coil 1 and the electromagnet 2 coincide with each other. The linear power supply is connected to the positive and negative poles of the Helmholtz coil 1 and the electromagnet 2 to provide the current required to generate the magnetic field; the Hall probe is built into the Helmholtz coil 1 and the electromagnet 2. Among them, the Helmholtz coil 1 and the electromagnet 2 are each equipped with a linear power supply and a Hall probe. The cooling device is used to cool the Helmholtz coil 1 and the electromagnet 2. When working, the Helmholtz coil 1 or the electromagnet 2 is selected to input the required magnetic field size, and the linear power supply adjusts the output current according to the magnetic field size measured by the Hall probe until the magnetic field size is stable. During the working process, the cooling device can be always turned on to avoid the burning of the Helmholtz coil 1 or the electromagnet 2.

[0047] When working, choose to use Helmholtz coil 1 and electromagnet 2, for example, use Helmholtz coil 1 first and then electromagnet 2. After the Helmholtz coil experiment is completed, the program controls the slide rail to move the laser to the electromagnet area and controls the magnetic field size generated by the electromagnet to start the experiment.

[0048] In some embodiments of the present invention, only the Helmholtz coil 1 or only the electromagnet 2 can be used as needed, or the Helmholtz coil 1 can be used first and then the electromagnet 2. During the operation, only one magnetic field generator (Helmholtz coil or electromagnet) will be controlled to work.

[0049] In some embodiments of the present invention, the cooling device is a water cooling device, and the water cooling flow path is connected in series, and the cold water first enters the Helmholtz coil 1, then enters the electromagnet 2, and finally flows into the chiller for re-cooling.

[0050] In some embodiments of the present invention, the magnetic field strength generated by the selected Helmholtz coil 1 after being powered on is 0-100mT, and the magnetic field strength generated by the selected electromagnet 2 after being powered on is 50-1000mT. In other embodiments, electromagnets or Helmholtz coils that can generate other required magnetic field sizes can also be placed according to the required magnetic field range, and the central axes of the magnetic fields of the electromagnet 2 and the Helmholtz coil 1 coincide with each other during placement, and the linear guide rail for switching the laser is extended.

[0051] There are reaction modules in the middle of the Helmholtz coil 1 and the middle of the electromagnet 2. The Helmholtz coil 1 includes two coils, and the electromagnet 2 includes two poles (such as Figure 1The two cylinders shown in the figure are placed so that the central axes of the magnetic fields of the Helmholtz coil 1 and the electromagnet 2 coincide with each other. A reaction module and a light intensity monitoring module are arranged between the two coils and between the two poles. The two catalytic reactors 6 in the two reaction modules are connected. During the experiment, there is no need to move the position of the catalytic reactor. To avoid contamination, after each set of experiments, the injection pump 10 can be switched to pump in solvent for cleaning.

[0052] Each reaction module includes a catalytic reactor 6, a multi-channel valve 13, an injection pump 10, a vacuum pump 12, an electronic vacuum pressure gauge 14, a check valve 15, and an inert gas mass flow meter 11; see Figure 3 The multi-channel valve 13 is a multi-inlet and one-outlet valve (in some embodiments of the present invention, it is 4-inlet and 1-outlet), including 1 outlet and multiple inlet ends. The valve center of the multi-channel valve 13 is the outlet, and the outlet is always connected to the catalytic reactor 6. The multiple inlet ends are respectively connected to the injection pump 10, the vacuum pump 12, and the inert gas mass flow meter 11 through pipelines, wherein the injection pump 10 can be provided with multiple to push different experimental sample solutions (in some embodiments of the present invention, the injection pump 10 is provided with two). An electronic vacuum pressure gauge 14 is also provided on the pipeline connected to the vacuum pump 12. When working, it needs to be turned to the corresponding position to be connected. The black lines in the figure are all pipelines, and the dotted lines represent the pipelines in the valve. The one-way valve 15 is connected to the rear end of the catalytic reactor 6 to prevent air from leaking from the end when vacuuming.

[0053] The multi-channel valve 13 is connected to different pipelines to realize functions such as vacuuming, blowing, and pushing different experimental sample solutions by different injection pumps.

[0054] In some embodiments of the present invention, Figure 3 As shown, two injection pumps 10 are provided. At the beginning of the reaction, the multi-channel valve 13 is switched to position a, and the vacuum pump 12 is turned on to evacuate the catalytic reactor 6. When the electronic vacuum pressure gauge 14 reads -98 kPa, it is switched to position b after 30 seconds, and the inert gas mass flow controller 11 is turned on to purge the catalytic reactor 6 with 100 sccm nitrogen for 60 seconds. After repeating three times, the catalytic reactor 6 is in an inert atmosphere. The multi-channel valve 13 is switched to position c, and one of the injection pumps 10 is turned on to perform the experiment of Application Example 1. It is switched to position d, and the other injection pump 10 is turned on to perform the experiment of Application Example 2.

[0055] In some embodiments of the present invention, the inert gas is nitrogen.

[0056] In some embodiments of the present invention, the catalytic reactor 6 is a cuvette reactor, preferably, a flow micro-reaction cuvette.

[0057] In some embodiments of the present invention, the size of the catalytic reactor 6 is 12.5*12.5 mm.

[0058] In some embodiments of the present invention, the catalytic reactor 6 is made of quartz and has an optical path of 10 mm.

[0059] In some embodiments of the present invention, the gap between the two coils in the Helmholtz coil 1 is 25 mm, and the distance between the two poles of the electromagnet 2 is 25 mm.

[0060] The switchable light source module comprises a linear guide rail 5 and at least one laser end collimator 4. A plurality of laser end collimators 4 are mounted on a slider of the linear guide rail 5, and the movement of the slider drives the movement of the laser end collimators 4.

[0061] The laser is generated from the laser, passes through the optical fiber, and finally emitted from the laser end collimator 4. The laser end collimator 4 is connected to the slider on the linear guide rail 5 through an optical support rod, and the lasers emitted by multiple laser end collimators 4 are of the same height. The direction in which the slider on the linear guide rail 5 moves is perpendicular to the laser emission direction.

[0062] In some embodiments of the present invention, there is one laser end collimator 4, one laser is provided, the laser is connected to the laser end collimator 4 through an optical fiber, the laser light source wavelength of the laser end collimator 4 is 365nm, the diameter of the end collimator is 65mm, the laser focal length is 250mm, and the spot size at the focal length is 2mm in diameter; the length of the linear guide 5 is 1000mm and is controlled by a stepper motor. In other embodiments, the laser end collimator 4 can be set to multiple, and different laser end collimators 4 can emit lasers of different wavelengths to the light intensity monitoring module. In this embodiment, multiple laser end collimators and lasers are provided, and multiple optical fibers are provided. The laser, the laser end collimator, and the optical fiber are provided in sequence.

[0063] Each light intensity monitoring module includes a light intensity monitoring module 8 on the incident light side and a light intensity monitoring module 9 on the outgoing light side, and the light intensity monitoring device is placed along the light path. The light intensity monitoring module on the incident light side is placed in front of the catalytic reactor 6, and the light intensity monitoring module on the outgoing light side is placed behind the catalytic reactor 6. The light intensity monitoring module 8 on the incident light side includes a beam splitter prism 7, a first photodiode and a first signal collector, the first photodiode is located above the beam splitter prism 7, and the signal collector is connected to the first photodiode. The laser emitted from the laser end collimator 4 is divided into two beams of light by the beam splitter prism 7, defined as a first beam of light and a second beam of light, wherein the first beam of light is finally projected onto the catalytic reactor 6, and the second beam of light passes through the beam splitter prism 7 and is projected vertically upward onto the first photodiode of the light intensity monitoring module 8 on the incident light side, and is converted into an electrical signal and collected by the first signal collector. The light intensity monitoring module 9 on the outgoing light side includes a second photodiode and a second signal collector arranged in sequence. The second photodiode is arranged close to the catalytic reactor. After the first beam of light passes through the catalytic reactor 6, it is projected onto the second photodiode of the outgoing light detection module 9, and is converted into an electrical signal and collected by the second signal collector, corresponding to the intensity of the outgoing light.

[0064] The above-mentioned embodiments of the present invention can realize the continuous adjustment of the magnetic field from 0 to 1 T, the switching of light sources, the automatic switching and replacement of samples during the photocatalytic process, and the monitoring of light intensity during the photocatalytic process. During the catalytic reaction, there is no need for manual intervention to adjust the magnetic field, switch the light source, and replace the sample, which effectively ensures the repeatability of the experiment while saving a lot of labor costs.

[0065] In some embodiments of the present invention, the size of the beam splitter prism 7 is 12.5*12.5 mm, and the beam splitting ratio is 30 / 70.

[0066] In some embodiments of the present invention, the beam splitter prism 7 is made of quartz.

[0067] In some embodiments of the present invention, the splitting ratio of the beam splitter prism 7 is 30%:70%. In other embodiments, the splitting ratio of the beam splitter prism 7 can be changed by replacing prisms with different coatings.

[0068] When the splitting ratio of the beam splitter 7 is 30%:70%, the laser emitted from the laser end collimator 4 is split by the beam splitter 7 into two beams of 30% and 70% intensity. The light with 70% intensity (the first beam) is finally projected onto the catalytic reactor 6, and the light with 30% intensity (the second beam) passes through the beam splitter 7 vertically upward and is projected onto the first photodiode of the incident light side light intensity monitoring module 8, and is converted into an electrical signal and collected by the first signal collector. The light intensity monitoring module on the outgoing light side includes a second photodiode and a second signal collector. The laser with 70% intensity passes through the catalytic reactor 6 and is projected onto the second photodiode of the outgoing light detection module 9, and is converted into an electrical signal and collected by the second signal collector, corresponding to the outgoing light intensity.

[0069] The method for catalysis using the device provided in the above embodiment comprises the following steps:

[0070] The switching light source module is used to make the emitted laser light enter the light intensity monitoring module between the two coils or the light intensity monitoring module between the two pole heads;

[0071] The incident laser is divided into two beams of light by a beam splitter prism, defined as a first beam of light and a second beam of light. The first beam of light is finally projected onto the catalytic reactor, and after passing through the catalytic reactor, is projected onto the second photodiode of the output light detection module, and is converted into an electrical signal and collected by the second signal collector; the second beam of light is projected onto the first photodiode of the light intensity monitoring module on the incident light side by a beam splitter prism and is converted into an electrical signal and collected by the first signal collector.

[0072] Among them, the light intensity relationship measured by the light intensity monitoring module on the incident light side is:

[0073]

[0074] In the formula, I 入射 is the intensity of the first beam of light after being split by the beam splitter prism, I 第一信号采集器 is the light intensity measured by the first signal collector, a is the splitting ratio, and the value is determined by the splitting ratio of the optical prism used. In some embodiments of the present invention, a=3 / 7, corresponding to a splitting ratio of 30%:70%.

[0075] In some embodiments of the present invention, the first photodiode and the second photodiode are both silicon photodiodes with a response wavelength of 200-1100 nm and a photosensitive area of ​​3*3 mm.

[0076] In some embodiments of the present invention, the devices are all fixed on an optical flat plate of 1200*900 mm. Specifically, the Helmholtz coil, the electromagnet, and the guide rail are fixed on the optical platform.

[0077] The formula for calculating the quantum yield is:

[0078]

[0079] AQY is the apparent quantum yield, v is the reaction rate, K is the number of electron transfers, A is the illumination area, λ is the wavelength of the incident light, (I 入射 -I 第二信号采集器 ) is expressed as the actual absorbed light intensity of the reaction, I 入射 is the intensity of the first beam of light after being split by the beam splitter prism, I 第二信号采集器 It is the light intensity measured by the second signal collector.

[0080] Application Example 1

[0081] This application example provides a magnetic field and photocatalytic reaction method, the magnetic field and photocatalytic method uses the device provided in the above embodiment, and the method includes the following steps:

[0082] In an inert atmosphere, 0.2 mmol of methyl p-chlorobenzoate, 1 mmol of N-methylpyrrole, 0.4 mmol of DIPEA, 5 mol% of photocatalyst, and 5 wt% of TX-100 were mixed with water to prepare a reaction solution, which was then drawn into a glass syringe for later use.

[0083] The photocatalyst is a phenothiazine catalyst PTH, the reaction liquid flow rate is 14uL / min, the magnetic field strengths generated by the electromagnet are 200 and 150mT respectively, and the light intensity is 150mW, and a photocatalytic dehalogenation coupling reaction is carried out under a magnetic field.

[0084] As shown in Table 1, when the magnetic field strength is 200 mT, the yield of 3aa is 32% and the yield of 4aa is 57%; when the magnetic field strength is 150 mT, the yield of 3aa is 31% and the yield of 4aa is 55%.

[0085] Application Example 2

[0086] This application example provides a magnetic field and photocatalytic combined reaction method. Compared with application example 1, the magnetic field is generated by a Helmholtz coil, and the intensities are 100 and 50 mT respectively.

[0087] As shown in Table 1, when the magnetic field strength is 100 mT, the yield of 3aa is 28% and the yield of 4aa is 54%; when the magnetic field strength is 50 mT, the yield of 3aa is 26% and the yield of 4aa is 51%.

[0088] Comparative Example 1

[0089] This comparative application example provides a magnetic field and photocatalytic combined reaction method. Compared with Application Example 1, the magnetic field strength is 0 (the magnetic field strength of the electromagnet is 0, and the magnetic field of the Helmholtz coil is 0), and the reaction module is placed in the Helmholtz coil.

[0090] As shown in Table 1, when the magnetic field strength provided by the Helmholtz coil is 0 mT, the yield of 3aa is 25% and the yield of 4aa is 46%.

[0091]

[0092]

[0093] Table 1

[0094] The magnetic field and photocatalytic combined reaction device provided in the aforementioned embodiment of the present invention can automatically adjust the magnetic field size from 0mT during the photocatalytic process, and can automatically switch the magnetic field generating device through a linear guide rail, and adjust the light intensity through the incident light and outgoing light intensity monitoring module, which can reduce the experimental operation steps and improve the experimental efficiency and experimental repeatability.

[0095] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A device combining magnetic field and photocatalysis, characterized in that: It includes a magnetic field generating module, a reaction module, a light intensity monitoring module and a switching light source module. The magnetic field generating module comprises a Helmholtz coil and an electromagnet, and the magnetic field axes of the Helmholtz coil and the electromagnet coincide with each other; The Helmholtz coil includes two coils, the electromagnet includes two poles, a reaction module and a light intensity monitoring module are arranged between the two coils and between the two poles, each reaction module includes a catalytic reactor, and each light intensity monitoring module includes an incident light side light intensity monitoring module and an outgoing light side light intensity monitoring module respectively located on both sides of the catalytic reactor; The laser emission position in the switching light source module is adjustable so that the emitted laser is emitted into the light intensity monitoring module between the two coils or the light intensity monitoring module between the two pole heads.

2. The device for combining magnetic field and photocatalysis according to claim 1, characterized in that: The magnetic field generating module also includes a power supply and a Hall probe. The Helmholtz coil and the electromagnet are both connected to the power supply. The power supply is used to provide the current required to generate the magnetic field. The Hall probe is arranged in the Helmholtz coil and the electromagnet.

3. The device for combining magnetic field and photocatalysis according to claim 1, characterized in that: The magnetic field generating module further comprises a cooling device, and the cooling device is used for cooling the Helmholtz coil and the electromagnet.

4. The device for combining magnetic field and photocatalysis according to claim 3, characterized in that: The cooling device is a water cooling device, which includes a water cooling flow path and a water chiller. The water cooling flow path and the water chiller are connected to form a loop, and the water cooling flow path flows through the Helmholtz coil and the electromagnet.

5. The device for combining magnetic field and photocatalysis according to claim 1, characterized in that: The switchable light source module comprises a linear guide rail and a laser end collimator slidably arranged on the linear guide rail. When in operation, the laser beam is emitted from the laser end collimator and incident on the light intensity monitoring module.

6. The device for combining magnetic field and photocatalysis according to claim 1, characterized in that: Each of the reaction modules also includes a multi-channel valve, a vacuum pump, an inert gas mass flowmeter, at least one injection pump and a one-way valve. The multi-channel valve includes an outlet end and multiple inlet ends. The outlet end is connected to the catalytic reactor. The multiple inlet ends are respectively connected to the injection pump, the vacuum pump, and the inert gas mass flowmeter through pipelines. The injection pump, the vacuum pump, and the inert gas mass flowmeter are arranged at the rear end of the catalytic reactor. When working, emptying, purging, and switching of different sample operations are carried out by switching to connect different inlet ends.

7. The device for combining magnetic field and photocatalysis according to claim 1, characterized in that: During operation, either the Helmholtz coil or the electromagnet is used to generate a magnetic field.

8. A magnetic field and photocatalytic combined device according to any one of claims 1 to 7, characterized in that: The incident light side light intensity monitoring module includes a beam splitter prism, a first photodiode and a first signal collector. The beam splitter prism is arranged opposite to the switching light source module, the first photodiode is located above the beam splitter prism, and the first signal collector is connected to the first photodiode.

9. The device for combining magnetic field and photocatalysis according to claim 8, characterized in that: The light intensity monitoring module on the output light side includes a second photodiode and a second signal collector which are arranged in sequence, and the second photodiode is arranged close to the catalytic reactor.

10. A method for catalysis using the device according to claim 9, characterized in that: The following steps are involved: The switching light source module is used to make the emitted laser light enter the light intensity monitoring module between the two coils or the light intensity monitoring module between the two pole heads; The incident laser is divided into two beams of light by a beam splitter prism, defined as a first beam of light and a second beam of light. The first beam of light is finally projected onto the catalytic reactor, and after passing through the catalytic reactor, is projected onto the second photodiode of the output light detection module, and is converted into an electrical signal and collected by the second signal collector; the second beam of light is projected onto the first photodiode of the light intensity monitoring module on the incident light side by a beam splitter prism and is converted into an electrical signal and collected by the first signal collector.

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