Device and method for combining magnetic field and photocatalysis

Abstract

The present invention discloses a device and method for combining magnetic field and photocatalysis. The device includes a magnetic field generating module, a reaction module, a light intensity monitoring module, and a switching light source module. The magnetic field control module includes a Helmholtz coil and an electromagnet that generate a magnetic field. The Helmholtz coil includes two coils, and the electromagnet includes two poles. A reaction module and a light intensity monitoring module are provided 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 intensity monitoring module and an outgoing light intensity monitoring module, respectively located on either side of the catalytic reactor. The laser emission position in the switching light source module is adjustable so that the emitted laser light enters the light intensity monitoring module between the two coils or the light intensity monitoring module between the two poles. The present invention can adjust the magnetic field from zero, and no manual intervention is required to adjust the magnetic field during the catalytic reaction.

Description

Technical Field

[0001] The present invention belongs to the technical field of magnetic field-regulated 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 and organic dyes and semiconductor material photocatalysts in recent years, visible light catalysis methodology has developed into one of the powerful synthetic means in organic synthesis, promoting the rapid development of organic synthetic chemistry.

[0003] Current research on photocatalytic organic reactions focuses on reaction selectivity and yield, as well as achieving reaction types unattainable by thermal catalysis. However, research on and improvement of photocatalytic quantum efficiency (QE) has been relatively limited. High QE / EE is a prerequisite for the industrial application of photocatalytic organic synthesis and holds significant research and industrial value. However, visible light photocatalysis is limited by the energy of visible light photons (i.e., 400-700 nm, 1.8-3.1 eV), and not all of this energy can be fully utilized. Intersystem crossing (ISC) and back electron transfer are both significant factors limiting the energy efficiency of photocatalytic organic reactions. Recently, the Nocera group at Harvard University utilized radical binding to suppress the electron back transport of twin radical pairs, thereby increasing QE. However, this approach requires the introduction of additional chemical reagents, contradicting the ideal of green chemistry, which emphasizes 100% atomic efficiency. Compared to light and electric fields, the use of static magnetic fields to control organic catalytic reactions is relatively unsatisfactory. 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 regulating photocatalytic organic reactions by magnetic fields.

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

[0005] 1. There is no real-time monitoring of light intensity in the photocatalytic device, making 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, comprising 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 includes 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, and a reaction module and a light intensity monitoring module are provided 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 enters 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 provided in the Helmholtz coil and the electromagnet.

[0013] Furthermore, the magnetic field strength generated by the Helmholtz coil when powered on is 0-100mT; the magnetic field strength generated by the electromagnet when powered on is 50-1000mT. The Helmholtz coil operates by generating a magnetic field when powered on. When powered off, it is simply a copper coil, so there is no magnetic field when powered off. The 0-100mT generated by the coil is the operating 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 powered off, the iron core has residual magnetism, and the pole head still has a magnetic field of approximately 50mT (measured value). The 50-1000mT generated by the electromagnet is the operating magnetic field strength range provided by the electromagnet manufacturer.

[0014] Furthermore, magnetic field generating modules are installed 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 results of finite element simulation, the 1% magnetic field uniformity area is approximately a cylindrical area with a diameter of the electromagnet pole minus 1.1 times the gap.)

[0015] Furthermore, the magnetic field generating module further includes a cooling device, which 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 chiller. The water cooling flow path and the chiller are connected to form a loop, and the water cooling flow path flows through the Helmholtz coil and the electromagnet.

[0017] Furthermore, the switchable light source module includes a linear guide and a laser end collimator slidably mounted on the linear guide. During operation, a 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, the laser beam emitted by the light source can be adjusted to enter the light intensity monitoring module between the two coils or between the two pole heads.

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

[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, multiple laser end collimators are provided, with laser focal lengths ranging from 150 to 350 mm. These laser spots are aligned using slide rails. Laser spots with different focal lengths are aligned and fixed to the linear guide rails. Subsequent left and right translation of the linear guide rails ensures the laser spots remain aligned.

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

[0022] Furthermore, the catalytic reactor is a cuvette reactor. Preferably, the cuvette reactor is any one of a common cuvette, an airtight 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 spectroscopic prism, a first photodiode and a first signal collector. The spectroscopic prism is arranged opposite to the switching light source module, the first photodiode is located above the spectroscopic 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-mentioned 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 spectroscopic prism, defined as the first beam of light and the second beam of light. The first beam of light is finally projected onto the cuvette reactor, passes through the cuvette reactor and is projected onto the second photodiode of the output light detection module, where it 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 spectroscopic 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 the incident light and the outgoing light in real time during the photocatalytic process, reducing the impact of light source instability on the experiment. Subsequently, the quantum yield in the photocatalytic process can be accurately calculated based on the difference between the incident light and the outgoing light.

[0039] 2. When no current flows through the electromagnet in the prior art, the tip still has a residual magnetic field of about 50mT, which can still interfere with the experiment. In the present invention, the Helmholtz coil can perform experiments from 0-100mT, and the electromagnet can perform experiments from 50mT to 1000mT. The combination of the two enables experiments with a continuously adjustable magnetic field from 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 experimental needs, reducing optical path deviation and experimental errors caused by manual operation. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0041] Figure 2 Schematic diagram of the reaction module and the 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-catalytic reactor; 7-beam splitter prism; 8-incident light side light intensity monitoring module; 9-outgoing light side light intensity monitoring module. The support part is omitted in the figure.

[0043] Figure 3 Schematic diagram of the reaction module in an embodiment of the present invention, including: 10 - syringe pump; 11 - inert gas mass flow controller; 12 - vacuum pump; 13 - multi-channel valve, with the dotted line representing the flow channel inside the valve; 14 - electronic vacuum pressure gauge; 15 - one-way valve. DETAILED DESCRIPTION

[0044] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only 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 making creative efforts 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 located on both sides of the outer wall of the reaction area. It includes a Helmholtz coil 1, an electromagnet 2, a cooling device, a linear power supply, and a Hall probe. The Helmholtz coil 1 and electromagnet 2 are positioned axially, with their magnetic field axes centered on each other. The linear power supply is connected to the positive and negative terminals of the Helmholtz coil 1 and electromagnet 2 to provide the current required to generate the magnetic field. The Hall probe is built into the Helmholtz coil 1 and electromagnet 2. Each Helmholtz coil 1 and electromagnet 2 is equipped with a linear power supply and a Hall probe. The cooling device cools the Helmholtz coil 1 and electromagnet 2. During operation, the desired magnetic field strength is input to either Helmholtz coil 1 or electromagnet 2. The linear power supply then adjusts the output current based on the magnetic field strength measured by the Hall probe until the magnetic field stabilizes. The cooling device can be kept on during operation to prevent burnout of the Helmholtz coil 1 or electromagnet 2.

[0047] When working, choose to use either Helmholtz coil 1 or electromagnet 2. For example, you can 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 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 operation, only one magnetic field generator (Helmholtz coil or electromagnet) is controlled to operate.

[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. 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 selected Helmholtz coil 1 generates a magnetic field strength of 0-100 mT when powered on, and the selected electromagnet 2 generates a magnetic field strength of 50-1000 mT when powered on. In other embodiments, electromagnets or Helmholtz coils capable of generating other desired magnetic field strengths may be placed according to the desired magnetic field range. The central axes of the magnetic fields of the electromagnet 2 and the Helmholtz coil 1 are aligned 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 provided between the two coils and between the two pole heads. 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, the syringe pump 10 can be switched to pump in solvent for cleaning after each set of experiments.

[0052] Each reaction module includes a catalytic reactor 6, a multi-channel valve 13, a syringe pump 10, a vacuum pump 12, an electronic vacuum pressure gauge 14, a one-way valve 15, and an inert gas mass flow controller 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 inlets and 1 outlet), including one outlet and multiple inlets. The center of the valve of the multi-channel valve 13 is the outlet, which is always connected to the catalytic reactor 6. The multiple inlets are connected to the injection pump 10, vacuum pump 12, and inert gas mass flow controller 11 through pipelines. The injection pump 10 can be set to multiple to push different experimental sample solutions (in some embodiments of the present invention, two injection pumps 10 are provided). An electronic vacuum pressure gauge 14 is also provided on the pipeline connected to the vacuum pump 12. When working, it needs to be rotated to the corresponding position to connect. The black lines in the figure are all pipelines, and the dotted lines represent the pipelines inside 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 syringe pumps 10 are provided. At the start 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 maintained for 30 seconds and then switched to position b. 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 this three times, the catalytic reactor 6 is now in an inert atmosphere. The multi-channel valve 13 is switched to position c, and one of the syringe pumps 10 is turned on to perform the experiment in Application Example 1. The multi-channel valve 13 is switched to position d, and the other syringe pump 10 is turned on to perform the experiment in 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 switching light source module includes a linear guide rail 5 and at least one laser end collimator 4. The multiple 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] Laser light is generated by the laser, passes through the optical fiber, and is ultimately emitted from the laser end collimator 4. The laser end collimator 4 is connected to the slider on the linear guide 5 via an optical support rod. The laser light emitted by multiple laser end collimators 4 is at the same height. The direction in which the slider on the linear guide 5 translates is perpendicular to the direction of laser emission.

[0062] In some embodiments of the present invention, a single laser end collimator 4 and a single laser are provided. The laser is connected to the laser end collimator 4 via an optical fiber. The laser light source wavelength of the laser end collimator 4 is 365 nm, the diameter of the end collimator is 65 mm, the laser focal length is 250 mm, and the spot size at the focal length is 2 mm in diameter. The linear guide rail 5 is 1000 mm long and controlled by a stepper motor. In other embodiments, multiple laser end collimators 4 can be provided, 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, with the laser, laser end collimator, and optical fiber being provided in a corresponding order.

[0063] Each light intensity monitoring module includes an incident light side light intensity monitoring module 8 and an outgoing light side light intensity monitoring module 9, and the light intensity monitoring device is placed along the light path. The incident light side light intensity monitoring module is placed in front of the catalytic reactor 6, and the outgoing light side light intensity monitoring module is placed behind the catalytic reactor 6. The incident light side light intensity monitoring module 8 includes a spectroscopic prism 7, a first photodiode and a first signal collector, the first photodiode is located above the spectroscopic 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 spectroscopic prism 7, defined as the first beam of light and the 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 spectroscopic prism 7 and is projected vertically upward 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 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 light intensity monitoring module 9 on the outgoing light side, and is converted into an electrical signal and collected by the second signal collector, corresponding to the intensity of the outgoing light.

[0064] The aforementioned embodiments of the present invention enable continuous adjustment of the magnetic field from 0 to 1 T, light source switching, automatic sample switching and replacement during the photocatalytic process, and monitoring of light intensity during the photocatalytic process. This eliminates the need for manual intervention to adjust the magnetic field, switch the light source, or change samples during the catalytic reaction, effectively ensuring experimental reproducibility while saving significant 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 light emitted from the laser end collimator 4 is split by the beam splitter 7 into two beams of light with intensities of 30% and 70%. The light with 70% intensity (the first beam) is ultimately 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, where it is converted into an electrical signal and collected by the first signal collector. The outgoing light side light intensity monitoring module includes a second photodiode and a second signal collector. The laser light with 70% intensity passes through the catalytic reactor 6 and is projected onto the second photodiode of the outgoing light side light intensity monitoring module 9, where it 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 spectroscopic prism, defined as the first beam of light and the second beam of light. The first beam of light is finally projected onto the catalytic reactor, and after passing through the catalytic reactor, it 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 spectroscopic 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 incident light side light intensity monitoring module is:

[0073]

[0074] Where, is the intensity of the first beam of light after being split by the beam splitter prism, is the light intensity measured by the first signal collector, is the splitting ratio, which 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 platform 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, is the reaction rate, is the number of electron transfers in the reaction, is the illuminated area, is the wavelength of incident light, Expressed as the actual absorbed light intensity of the reaction, is the intensity of the first beam of light after being split by the beam splitter prism, It is the light intensity measured by the second signal collector.

[0080] Application Example 1

[0081] This application example provides a method for combining a magnetic field with photocatalysis. The method uses the device provided in the above embodiment and 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 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 the magnetic field.

[0084] As shown in Table 1, when the magnetic field strength was 200 mT, the yield of 3aa was 32% and the yield of 4aa was 57%; when the magnetic field strength was 150 mT, the yield of 3aa was 31% and the yield of 4aa was 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 was 100 mT, the yield of 3aa was 28% and the yield of 4aa was 54%; when the magnetic field strength was 50 mT, the yield of 3aa was 26% and the yield of 4aa was 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 intensity is 0 (the electromagnetic magnetic field intensity is 0, and the Helmholtz coil magnetic field 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] Table 1

[0093]

[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 is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily 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 is not limited to the embodiments shown herein but is intended to conform 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 magnetic field generating module, reaction module, light intensity monitoring module and switching light source module. The magnetic field generating module includes 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, and the electromagnet includes two poles. A reaction module and a light intensity monitoring module are provided between the two coils and between the two poles. Each reaction module includes a catalytic reactor. 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 two catalytic reactors in the two reaction modules are connected; The laser emission position in the switching light source module is adjustable so that the emitted laser enters 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 further 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 provided in both 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 includes a cooling device, which is used to cool 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 chiller. The water cooling flow path and the 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 switching light source module includes a linear guide rail and a laser end collimator slidably arranged 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.

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 flow controller, 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, and the multiple inlet ends are respectively connected to the injection pump, vacuum pump, and inert gas mass flow controller through pipelines. The injection pump, vacuum pump, and inert gas mass flow controller are arranged at the rear end of the catalytic reactor. During operation, emptying, purging, and switching of different sample operations are performed 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 device for combining magnetic field and photocatalysis according to any one of claims 1 to 7, characterized in that: The incident light side light intensity monitoring module includes a spectroscopic prism, a first photodiode and a first signal collector. The spectroscopic prism is arranged opposite to the switching light source module, the first photodiode is located above the spectroscopic 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 spectroscopic prism, defined as the first beam of light and the second beam of light. The first beam of light is finally projected onto the catalytic reactor, and after passing through the catalytic reactor, it 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 spectroscopic prism and is converted into an electrical signal and collected by the first signal collector.

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