CN116008384A - An ultrasonic atomization photoionization source device and its application method - Google Patents

Abstract

The invention provides an ultrasonic atomization photoionization source device and its use method. The ultrasonic atomization photoionization source device includes a motor plug; a sampling pad; an ultrasonic atomization system is arranged on the sampling pad, which includes an electrically connected ultrasonic mist The atomization chip and the atomization vibration element; the thermal analysis heater is installed above the top of the motor, and a thermal analysis room is opened in the center, and a metal grid is arranged in the thermal analysis room, and the atomization vibration element is directly below it, and the atomization vibration element There is a space for the atomization vibrating element to vibrate between the metal grid and the vacuum ultraviolet lamp, which is installed on the top of the thermal analysis heater and used for photoionization and catalytic samples. When the device is working, the sample solution undergoes thermal analysis and photocatalytic ionization reactions rapidly and synchronously after ultrasonic atomization. Ultrasonic atomization assists thermal analysis and photoionization to increase the concentration and speed of gasification of the sample solution, further reducing the dead time and dead volume of the test. , improve the detection sensitivity and efficiency.

Description

An ultrasonic atomization photoionization source device and its application method

technical field

The invention relates to the technical field of detection and analysis equipment, in particular to an ultrasonic atomization photoionization source device.

Background technique

More recently, the industrial production of organometallics, pharmaceuticals, and pesticides produces a variety of organic pollutants that pass through the food chain in the form of metabolites in human urine and feces, causing further harm to the environment, usually Concentration levels from ng.L ^-1 to μg.L ^-1 were detected in water sources, sediments and soils. Some pollutants are highly stable and poorly biodegradable, which may cause potential adverse effects on human health. TiO-based photocatalysis is considered to be an effective way to remove these organic pollutants and an effective way to recover clean energy from wastewater. It is worth noting that, although studies to elucidate the oxidation pathways of single organic pollutants in titania-based photocatalytic processes are increasing, there is still much room for development in real-time monitoring of photocatalytic reactions.

In traditional monitoring techniques, the detection of photocatalytic reaction intermediates and products is carried out by electron spin resonance (ESR) spectroscopy, ultraviolet/visible light (UV/Vis) spectroscopy, capillary electrophoresis (CE), nuclear magnetic resonance (NMR) and layer analyzed to study. However, these detection techniques are time-consuming and require complex sample pretreatment. The sample needs to go through liquid-liquid extraction, filtration and other pretreatment steps before the detection can be started, which will cause certain pollution and loss to the sample. Second, some reaction intermediates have short lifetimes and low concentrations in aqueous solutions, making them difficult to separate and detect. The above limitations limit the accurate interpretation of the reaction mechanism by the detection technology, and it is more difficult to monitor the progress of the photocatalytic reaction in real time.

Vacuum ultraviolet light can ionize polar and non-polar molecules, and has a wide range of ionizable compounds. The sampling device of the current vacuum ultraviolet photoionization technology is basically in a different space from the photoionization element division. The prior art CN107238653A discloses A mass spectrometry detection device for ultrasonic atomization extraction of non-volatile organic compounds in water was developed. The sample has a certain transportation distance from the reaction source to the photoionization, and needs to be transported through a transport hose. During this transportation process, the intermediate structure of the reaction It is easy to change, and the dead time of sample detection is too long, which affects the accuracy of detection. For the photocatalytic reaction with short reaction time, the detection result of the device has delay and inaccuracy.

Prior art CN113406184B discloses an in-situ thermal analysis photoionization device for improving the sensitivity of mass spectrometry drug detection, the device mainly includes an in-situ thermal analysis cell, a peek material insulation shell, a stainless steel intake pipe, a radio frequency lamp, a carrier gas inlet and a stainless steel metal Capillary outlet, etc., the device performs in-situ thermal analysis of drugs, and then uses radio frequency lamps for photoionization, which simplifies the structure of thermal analysis and sample injection, and maintaining high temperature thermal analysis also improves the sensitivity of drug detection, but in the face of non-volatile liquid When detecting organic pollutants, the device only relies on the heating of the in-situ thermal analysis cell, and it is difficult to quickly volatilize the sample solution into a gaseous state for photoionization. Too long heating and volatilization will lead to low detection sensitivity and short-term detection reactions For intermediates, the dead time and dead volume are too large to ensure the accuracy of the test results.

Contents of the invention

In order to solve the problems of excessive dead time and dead volume and low sensitivity in sample analysis and detection in traditional ultraviolet photoionization detection technology, the present invention provides an ultrasonic atomization photoionization source device, including:

motor head;

A sampling pad, which is detachably arranged on the top of the motor;

An ultrasonic atomization system, which is arranged on the sample pad, is used to ultrasonically atomize the sample solution. The ultrasonic atomization system includes a fixed ring and an electrically connected ultrasonic atomization chip and an atomization vibrating element. The atomization The vibrating element is used to atomize the sample solution dropped on it, and the atomizing vibrating element includes a mounting ring and an atomizing shrapnel fixed on the mounting ring, and the atomizing shrapnel is a metal sheet for carrying sample solution;

Thermal analysis heater, which is installed above the top of the motor, there is a gap suitable for inserting the sample pad between the motor top and the thermal analysis heater, and the thermal analysis heater is provided with a hole through which the upper and lower ends , the hole is a thermal analysis chamber, the thermal analysis chamber is provided with a metal grid, and the atomization vibration element is located directly below the thermal analysis chamber;

A vacuum ultraviolet lamp, which is installed and against the top of the thermal desorption heater, the light source of the vacuum ultraviolet lamp is directed towards the thermal desorption chamber, and the vacuum ultraviolet lamp is used for photoionization and photocatalysis gaseous samples;

When the ultrasonic atomization photoionization source device is working, the sample injection pad is inserted into the gap between the motor top and the thermal desorption heater, and the motor top moves upward until the thermal desorption heater is pressed. Close to the atomization vibrating element, there is a space for the atomization shrapnel to vibrate between the atomization shrapnel and the metal grid.

Compared with the prior art that vaporizes the sample solution only by heating, the ultrasonic atomization system of the present invention cooperates with the thermal desorption heater to atomize the sample solution into small droplets, and the heating area of the small droplets is larger, so that the gasification speed Faster, greatly increasing the gasification concentration of the sample solution, reducing the proportion of components in the sample gas that cannot be retained by the stationary phase of the chromatographic column to reduce the dead volume, making it easier to be detected by analytical instruments; vacuum ultraviolet lamp, thermal desorption heater It is set to run in the same chamber as the atomization vibration element, and there is a space for the atomization vibration element to vibrate between the atomization vibration element and the metal grid to ensure the effect of ultrasonic atomization, which is conducive to the ultrasonic atomization of the sample solution and volatilization into After the gaseous state, the thermal analysis reaction and the photoionization catalytic reaction are carried out rapidly and synchronously, the gaseous sample is ionized to produce more ions, the concentration of the sample gas is further increased, and the dead volume and dead time of the detection are reduced, thereby improving the sensitivity and accuracy of the analysis and detection; the present invention The thermal analysis chamber is directly above the atomization vibrating element. The metal grid not only allows the atomized sample solution to volatilize into a gaseous state, but also preheats the gaseous sample to improve the efficiency of the subsequent thermal analysis reaction; the sample solution Ultrasonic atomization, thermal desorption reaction and photoionization catalytic reaction are carried out in the same chamber, which improves the volatilization efficiency of the sample solution, thereby shortening the time-consuming analysis and detection, and effectively improving the detection efficiency; the atomization vibration element can carry the sample solution, in the Driven by the ultrasonic atomization chip, without extracting and filtering the sample solution, the target detection substance can be atomized into small liquid droplets and then quickly volatilized into a gaseous state by heating, and the next step of thermal analysis and photocatalytic ionization reaction is carried out, which simplifies the sample pretreatment process. step.

Preferably, the ultrasonic atomization system further includes a fixing ring, the fixing ring is fixedly connected with the sampling pad, and pressed against the upper surface of the mounting ring, the middle through hole of the fixing ring is located in the directly above the atomized shrapnel. The fixing ring provides mechanical fixation for the atomizing vibrating element, and separates the thermal desorption heater and the atomizing vibrating element, so that there is sufficient space between the atomizing vibrating element and the metal grid, and the atomizing shrapnel can perform ultrasonic vibration normally. Ensure the ultrasonic atomization effect of the sample solution, and improve the subsequent thermal analysis reaction and photoionization reaction efficiency.

Preferably, there is a height difference between the atomizing shrapnel and the top of the installation ring. The height of the top of the installation ring is greater than the height of the atomizing shrapnel to ensure that when the device is running, there is sufficient space between the atomizing shrapnel and the metal grid for the ultrasonic vibration of the atomizing shrapnel to ensure that the solution can be ultrasonically atomized into small droplets .

Preferably, the sampling pad is provided with a power supply for supplying power to the ultrasonic atomization system, the thermal desorption heater and the vacuum ultraviolet lamp. The power supply is set on the sampling pad to supply power to the device, which can make the device easy to carry and meet the needs of on-site testing.

Preferably, one end of the sampling pad is provided with a base, the upper end of the base is provided with an annular placement groove and an avoidance groove located inside the annular placement groove, and the lower end of the installation ring is placed in the annular placement groove Inside, the avoidance groove is located directly below the atomizing shrapnel. There is a groove on the base, which is suitable for placing the atomization vibration element, so as to prevent the atomization vibration element from detaching from the sampling pad during operation and affect the ultrasonic atomization. An avoidance groove is set to reserve enough space for the ultrasonic vibration of the atomization shrapnel to improve the ultrasonic atomization effect. .

Preferably, the thermal desorption heater is provided with a vacuum port and a carrier gas inlet, and the vacuum port and the carrier gas inlet are connected to the thermal desorption chamber. The vacuum interface can be used to connect analytical and detection instruments, detect photoionization products in a straight line, reduce transportation time, and realize real-time monitoring of reaction intermediates.

Preferably, a capillary is provided in the vacuum interface, one end of the capillary is connected to the thermal analysis chamber, the other end is used to connect to the analysis and detection device, and the carrier gas inlet is connected to the carrier gas system. The capillary in the vacuum interface is connected to the analysis and detection device to realize the online monitoring of the sample, reduce the transmission process, and further improve the accuracy of the detection of the photocatalytic ionization reaction intermediate.

Preferably, the thermal analysis chamber has a diameter of 5-15mm and a height of 8-20mm. A thermal analysis chamber with a reasonable volume can completely accommodate the reaction gas, and make the reaction gas be heated more fully, and the thermal analysis reaction is more complete.

Preferably, the thickness of the metal grid is 0.5-1.5 mm, the mesh number is 10-70 mesh, and the material of the metal grid is pure metal or alloy. Metal or alloy metal grids are easy to transfer heat and reduce heat loss. The temperature of the metal grid is consistent with the temperature of the thermal analysis chamber. Controlling a reasonable thickness and mesh of the metal grid can speed up the heating and volatilization of the atomized small droplets of the sample. , It can also preheat the sample to improve the efficiency of the subsequent thermal analysis reaction.

The present invention also provides a method for using the above-mentioned ultrasonic atomization photoionization source device, comprising the following steps: dripping the sample solution onto the atomization shrapnel of the atomization vibrating element, One end of the atomization vibration element is inserted between the motor top and the thermal desorption heater; the control program, the motor top pushes up the sample pad until the bottom of the thermal desorption heater presses the atomization vibration element, the thermal desorption heater starts to heat and The heat is transferred to the metal grid, and the temperature of the thermal analysis chamber and the metal grid is controlled to 50-150°C; the ultrasonic atomization chip controls the atomization vibration element to perform ultrasonic vibration, and the sample solution on the atomization shrapnel is ultrasonically atomized into Small droplets; the small droplets of the sample contact the metal grid and volatilize into a gaseous sample, and the vacuum ultraviolet lamp is irradiated on the gaseous sample, and the gaseous sample is subjected to thermal analysis and photoionization catalytic reaction in the thermal analysis chamber; the carrier gas enters from the carrier gas The mouth enters the thermal analysis chamber and mixes with the reaction product gas, and the mixed gas is sent to the analysis and detection instrument for detection.

The beneficial effects of the present invention are: the sample solution can be directly added dropwise on the atomized shrapnel without complicated pretreatment processes such as extraction or filtration, the pretreatment steps are simple, and the sample injection is convenient; the atomization vibration of the device The element, the thermal desorption heater and the vacuum ultraviolet lamp form an integrated chamber, so that the sample solution is ultrasonically atomized and quickly volatilized into a gaseous state after passing through the metal grid, and then thermal desorption and photocatalytic ionization reactions occur, which is beneficial to shorten the time-consuming analysis and detection , to improve the detection efficiency; the metal grid set in the thermal analysis chamber can accelerate the vaporization of small droplets of the atomized sample into a gaseous state, and can also preheat the sample to improve the efficiency of the subsequent thermal analysis reaction; ultrasonic atomization assisted thermal analysis The reaction and photoionization catalytic reaction can increase the concentration of sample vaporization, thereby reducing the dead time and dead volume of analysis and detection, and improving the sensitivity of analysis and detection; the thermal analysis chamber is aligned with the atomization vibration element, and the sample is atomized into small droplets Directly enter the thermal analysis chamber to carry out thermal analysis reaction and photocatalytic ionization reaction simultaneously. Photoionization and thermal analysis reaction can promote the ionization of sample gas to produce more ions, increase the concentration of gaseous samples, thereby improving the sensitivity of detection, so that the detection instrument can detect light in real time. The intermediate structure of the catalytic ionization reaction provides an accurate explanation for the mechanism of the photocatalytic ionization reaction.

Description of drawings

1 is a cross-sectional view of an ultrasonic atomization photoionization source device provided in a specific embodiment of the present invention;

2 is a cross-sectional view of the structure of the ultrasonic atomization photoionization source device provided by the specific embodiment of the present invention;

Fig. 3 is a partially enlarged view of the structural cross-sectional view of the ultrasonic atomization photoionization source device provided by the specific embodiment of the present invention;

Fig. 4 is the mass spectrogram of benzotrifluoride and alcohol reaction intermediate in the embodiment 2 of the specific embodiment of the present invention;

Fig. 5 is the mass spectrogram of 1,3-bromoquinoline and phenylboronic acid in tetrakistriphenylphosphine palladium catalytic reaction intermediate in the embodiment 3 of the specific embodiment of the present invention;

Fig. 6 is the chemical reaction formula of benzotrifluoride and alcohol reaction in the embodiment 2 of the specific embodiment of the present invention;

Fig. 7 is the chemical reaction formula of the reaction between 1,3-bromoquinoline and phenylboronic acid under the catalysis of tetrakistriphenylphosphine palladium in Example 3 of the specific embodiment of the present invention.

Explanation of reference signs:

1-motor head; 2-injection pad; 3-power supply; 4-ultrasonic atomization system; 5-thermal desorption heater; 6-metal grid; 7-vacuum ultraviolet lamp; ; 41-ultrasonic atomization chip; 42-atomization vibration element; 43-fixed ring; 51-thermal analysis chamber; 52-vacuum interface; 53-carrier gas inlet.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions 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 It is a part of embodiments of the present invention, but not all embodiments. The components of the embodiments of the invention generally described and illustrated in the figures herein may be arranged and designed in a variety of different configurations.

It should be noted that similar symbols and letters denote similar items in the following figures, therefore, once an item is defined in one figure, it does not require further definition and explanation in subsequent figures.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, or in a specific orientation. construction and operation, therefore, should not be construed as limiting the invention.

Example 1

As shown in Fig. 1, Fig. 2 and Fig. 3, an embodiment of the present invention provides an ultrasonic atomization photoionization source device, its structure mainly includes: motor plug 1, sampling pad 2, power supply 3, ultrasonic atomization system 4, Thermal analysis heater 5, metal grid 6, vacuum ultraviolet lamp 7.

The motor head 1 faces the sample pad 2, and the motor head 1 will lift the sample pad 2 through the program control. The sample pad 2 is welded with a battery slot, which is used to install the power supply 3, and the power supply 3 uses a button battery for ultrasonic atomization. System 4, thermal desorption heater 5 and vacuum ultraviolet lamp 7 provide power;

The ultrasonic atomization system 4 includes an ultrasonic atomization chip 41, an atomization vibration element 42 and a fixed ring 43. The ultrasonic atomization chip 41 is installed on the sample pad 2 through bolt connection, and the ultrasonic atomization chip 41 is electrically connected to the atomization vibration element 42. Sexual connection, the atomizing vibrating element 42 is a metal one-piece element, including a mounting ring and an atomizing shrapnel, the upper and lower surfaces of the central axial direction of the mounting ring are provided with grooves, and an atomizing shrapnel is formed between the two grooves;

The sample injection pad 2 is welded with a round table base, the top of the round table base has a ring-shaped placement groove 21, the atomization vibrating element 42 has a ring-shaped mounting ring, and the geometric center of the ring-shaped mounting ring has an atomization sheet, and the top of the mounting ring is in contact with the mist. There is a height difference between the atomized shrapnel, the atomized shrapnel is parallel to the end face of the annular installation ring, there is a space for the atomized shrapnel to vibrate ultrasonically between the atomized shrapnel and the metal grid 6, and one end of the installation ring falls and is welded to the place In the groove 21, an avoidance groove 22 is also provided on the inner side of the placement groove 21. The avoidance groove 22 can also provide a vibration space for the atomized shrapnel to ensure that the atomized shrapnel can work normally. The inner diameter of the placement groove 21 is larger than the diameter of the avoidance groove 22;

The fixed ring 43 is a ring structure, the bottom of the fixed ring 43 is fitted and welded to the upper surface of the atomizing vibrating element 42 and the groove on the top of the round platform base of the sampling pad 2, and the atomizing vibrating element 42 is fixed by fitting welding, and fixed The middle through hole of the ring 43 is aligned with the atomizing shrapnel of the atomizing vibrating element 42, which can ensure the stability of the ultrasonic vibration and prevent the atomizing vibrating element 42 from detaching from the round platform base of the sampling pad 2 due to vibration, and the fixed ring 43 further separates the The atomizing shrapnel and the metal grid 6 provide sufficient ultrasonic vibration space for the atomizing shrapnel to ensure the ultrasonic atomization effect of the sample solution.

The thermal analysis heater 5 is used to heat and analyze gaseous samples. The temperature of the thermal analysis chamber 51 is heated to 150°C through the thermal analysis heater 5 to ensure that all the gaseous samples are thermally analyzed and reacted, and the gaseous state is maintained. The thermal analysis heater 5 It is a cylinder with a hollow structure, and this hollow structure forms a thermal analysis chamber 51. The diameter of the bottom surface of the thermal analysis chamber 51 is 15mm, and the height is 20mm. pressure, the bottom surface of the thermal analysis heater 5 is pressed on the top of the ultrasonic fixed member, and the inner wall of the thermal analysis heater 5 is provided with a vacuum port 52 with a diameter of 1 mm. A capillary is inserted at the vacuum port 52, and the analysis and detection device is connected through the capillary. The inner wall is also provided with a carrier gas inlet 53 with a diameter of 1mm, which is used to connect the carrier gas system. The flow rate of the carrier gas is controlled to 350mL/min. The auxiliary reagent added in the carrier gas can improve the efficiency of photocatalytic ionization and remove samples. residual.

The metal grid 6 is fixed on the bottom of the thermal desorption heater 5 by riveting; the thickness of the metal grid 6 is 1.5 mm, the mesh number is 70 mesh, and the aperture is 0.45 mm; the material of the metal grid 6 is pure metal or alloy, and its It is easy to conduct heat, keep the temperature of the metal grid 6 and the thermal analysis chamber 51 consistent, the atomized sample droplets are volatilized into gaseous samples when they pass through the holes of the metal grid 6, and the samples are preheated to a certain temperature, which improves the subsequent Heating efficiency of thermal desorption reaction.

The vacuum ultraviolet lamp 7 is fixed on the top of the thermal analysis chamber 51 through threaded connection, and the light source of the vacuum ultraviolet lamp 7 is directed towards the thermal analysis chamber 51. The vacuum ultraviolet lamp 7 emits energy with a specific wavelength of 10.3-10.8eV to accelerate the photoionization of the solution. The bottom of the ultraviolet lamp 7 is pressed on the top of the thermal analysis heater 5, and the atomized sheets of the vacuum ultraviolet lamp 7, the thermal analysis chamber 51, the metal grid 6 and the atomizing vibrating element 42 are all on the same axis direction and the vacuum ultraviolet lamp 7 , the thermal analysis heater 5, and the atomizing vibrating element 42 form a cavity, and the vacuum ultraviolet lamp 7 is aimed at the atomized sheet through the thermal analysis chamber 51, which can improve the photocatalytic efficiency of the sample. The sample solution is from ultrasonic atomization to thermal analysis and The photoionization catalytic reaction is carried out in the same chamber. After the sample is atomized into small droplets, it directly enters the thermal analysis chamber for simultaneous thermal analysis reaction and photocatalytic ionization reaction. The photoionization and thermal analysis reactions can promote the ionization of the sample gas to produce more ions. Increase the concentration of gaseous samples, thereby improving the sensitivity of detection, greatly shortening the dead time and dead volume of samples from ultrasonic atomization to analytical instruments, and realizing real-time monitoring of reaction intermediates with short reaction times, which meets the on-site online monitoring of organic chemical reactions demand.

The atomized sheet is used to carry the sample solution. After dripping the sample solution, disassemble the sampling pad 2 between the thermal desorption heater 5 and the motor head 1. The program controls the motor head 1 to lift the sampling pad 2 and heat it with the thermal desorption. The metal grid 6 riveted by the device 5 presses the fixed ring 43, and at this time, the light source of the vacuum ultraviolet lamp 7 passes through the thermal analysis chamber 51 and the metal grid 6 and directly irradiates the atomized sheet of the atomizing vibrating element 42, and the program starts the ultrasonic mist The photoelectric ionization source device is running, and driven by the ultrasonic atomization chip 41, the atomized sheet vibrates acoustically, so that the sample solution is atomized off-line, heated by the thermal analysis heater 5, and the atomized sample passes through the metal grid 6 The gaseous sample is heated and volatilized into a gaseous sample. The gaseous sample enters the thermal analysis chamber and is irradiated by the vacuum ultraviolet lamp 7. The thermal analysis reaction and the photocatalytic ionization reaction occur simultaneously. The carrier gas enters the thermal analysis chamber 51 through the carrier gas inlet 53 to meet the gaseous product, and the mixed gas enters The vacuum interface 52 is then sent into the analysis instrument through the capillary for on-line detection.

Example 2

In this example, the ultrasonic atomization photoionization source device of Example 1 is used for further analysis experiments.

The reaction of Williamson synthetic ether uses trifluorotoluene and alcohol reaction formula, takes a sample during the reaction, puts the sample solution into the atomized sheet of the atomized vibrating element 42, and inserts the end of the atomized vibrating element 42 provided with the sampling pad 2 Between the motor head 1 and the thermal analysis heater 5, the program control closes the motor head 1, the atomization vibration element 42 on the sampling pad 2 is aligned with the thermal analysis chamber 51, and the thermal analysis heater 5 is adjusted so that the temperature of the thermal analysis chamber 51 The temperature is 150°C, the carrier gas flow rate is 200mL/min, the vacuum port 52 is connected to the inlet of the ion trap mass spectrometer, and the ultrasonic atomization photoionization source device is turned on for detection, and the mass spectrum shown in Figure 2 is measured.

The reaction formula of trifluorotoluene and alcohol reaction is shown in Figure 6.

Example 3

In this example, the ultrasonic atomization photoionization source device of Example 1 is used for further analysis experiments.

The reaction in Suzuki-Miyaura uses the reaction formula of 3-bromoquinoline and phenylboronic acid under the catalysis of tetrakistriphenylphosphine palladium. During the reaction, samples are taken, and the sample liquid is dropped into the atomization vibration element of the ultrasonic atomization photoionization source device. 42, put the sample solution into the atomized sheet of the atomized vibrating element 42, insert the end of the sample injection pad 2 provided with the atomized vibrating element 42 between the motor plug 1 and the thermal desorption heater 5, and program control Turn on the motor head 1, align the atomization vibrating element 42 on the sampling pad 2 with the thermal desorption chamber 51, adjust the thermal desorption heater 5 so that the temperature of the thermal desorption chamber 51 is 50°C, the carrier gas flow rate is 200mL/min, and the vacuum port 52 Connect the injection port of the ion trap mass spectrometer, turn on the ultrasonic atomization photoionization source device for detection, and measure the mass spectrum of the oxidation addition intermediate as shown in Figure 3.

The reaction formula of 3-bromoquinoline and phenylboronic acid under the catalysis of tetrakistriphenylphosphine palladium is shown in Figure 7.

Combining Figure 4 and Figure 5, the ultrasonic atomization photoionization source device provided by the present invention can ultrasonically atomize the sample solution into small droplets, cooperate with the thermal desorption heater to improve the efficiency of sample volatilization by heat, and the gas sample can undergo thermal desorption reaction and photocatalysis at the same time The ionization reaction increases the concentration of the gas sample, thereby improving the detection sensitivity and shortening the time-consuming detection, realizing real-time monitoring of the intermediate structure of the photocatalytic reaction, which helps to accurately explain the reaction mechanism of the photocatalytic ionization reaction, and has broad application prospects .

Although the present disclosure is disclosed as above, the protection scope of the present disclosure is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present disclosure, and these changes and modifications will all fall within the protection scope of the present invention.

Claims (10)

1. An ultrasonic atomizing photoionization source device comprising:

a motor plug (1);

the sample injection pad (2) is detachably arranged on the motor plug (1);

the ultrasonic atomization system (4) is arranged on the sample injection pad (2) and is used for ultrasonically atomizing a sample solution, the ultrasonic atomization system (4) comprises an ultrasonic atomization chip (41) and an atomization vibration element (42) which are electrically connected, the atomization vibration element (42) is used for atomizing the sample solution dropwise added on the ultrasonic atomization chip, the atomization vibration element (42) comprises a mounting ring and an atomization elastic sheet fixed on the mounting ring, and the atomization elastic sheet is a metal sheet and is used for bearing the sample solution;

the thermal analysis heater (5) is arranged above the motor plug (1), the thermal analysis heater (5) is provided with a hole which is vertically communicated, the hole is a thermal analysis chamber (51), a metal grid (6) is arranged in the thermal analysis chamber (51), and the atomization vibration element (42) is positioned under the thermal analysis chamber (51);

a vacuum ultraviolet lamp (7) mounted and abutted on top of the thermal analysis heater (5), a light source of the vacuum ultraviolet lamp (7) facing the thermal analysis chamber (51), the vacuum ultraviolet lamp (7) being used for photoionization and photocatalysis of gaseous samples;

when the ultrasonic atomization photoionization source device works, the sample feeding pad (2) is inserted into a gap between the motor plug (1) and the thermal analysis heater (5), the motor plug (1) moves upwards until the thermal analysis heater (5) compresses the atomization vibrating element (42), and a space for vibration of the atomization elastic sheet is reserved between the atomization elastic sheet and the metal grid (6).

2. The ultrasonic atomizing photoionization source device according to claim 1, wherein the ultrasonic atomizing system (4) further comprises a fixing ring (43), the fixing ring (43) is fixedly connected with the sample injection pad (2) and is pressed on the upper surface of the mounting ring, and a middle through hole of the fixing ring (43) is positioned right above the atomizing shrapnel.

3. The ultrasonic atomizing photoionization source device of claim 1 or 2, wherein there is a height differential between the atomizing spring and the upper surface of the mounting ring.

4. The ultrasonic atomizing photoionization source device according to claim 1, wherein the sample feeding pad (2) is provided with a power supply (3) for supplying power to the ultrasonic atomizing system (4), the thermal analysis heater (5) and the vacuum ultraviolet lamp (7).

5. The ultrasonic atomization photoionization source device according to claim 1, wherein a base is arranged at one end of the sample injection pad (2), an annular placing groove (21) and an avoidance groove (22) positioned at the inner side of the annular placing groove are arranged at the upper end of the base, the lower end of the mounting ring is placed in the annular placing groove (21), and the avoidance groove (22) is positioned under the atomization elastic sheet.

6. The ultrasonic atomizing photoionization source device according to claim 1, wherein a vacuum interface (52) and a carrier gas inlet (53) are provided on the thermal desorption heater (5), and the vacuum interface (52) and the carrier gas inlet (53) are connected to the thermal desorption chamber (51).

7. The ultrasonic atomizing photoionization source device of claim 6, wherein a capillary is disposed in the vacuum port (52), one end of the capillary is connected to the thermal analysis chamber (51), the other end is connected to the analysis and detection device, and the carrier gas inlet (53) is connected to the carrier gas system.

8. An ultrasonic atomizing photoionization source device of claim 1, wherein the thermal analysis chamber (51) has a diameter of 5-15mm and a height of 8-20mm.

9. The ultrasonic atomizing photoionization source device according to claim 1, wherein the thickness of the metal grid (6) is 0.5-1.5mm, the mesh number is 10-70, and the metal grid (6) is made of pure metal or alloy.

10. A method of using an ultrasonic atomizing photoionization source device of any of claims 1-9, comprising the steps of: dripping a sample solution onto an atomization elastic sheet of an atomization vibrating element (42), and inserting one end of a sample injection pad (2) provided with the atomization vibrating element (42) between a motor plug (1) and a thermal analysis heater (5); the control program is that the motor plug (1) jacks up the sample feeding pad (2) until the bottom of the thermal analysis heater (5) is tightly pressed against the atomization vibrating element (42), the thermal analysis heater (5) starts to heat and transfer heat to the metal grid (6), and the temperature of the thermal analysis chamber (51) and the temperature of the metal grid (6) are controlled to be 50-150 ℃; an ultrasonic atomization chip (41) controls an atomization vibration element (42) to perform ultrasonic vibration, and a sample solution on an atomization elastic sheet is subjected to ultrasonic atomization into small liquid drops; the sample droplets contact the metal grid (6) and volatilize into a gaseous sample by heating, a vacuum ultraviolet lamp (7) irradiates the gaseous sample, and the gaseous sample is subjected to thermal analysis and photoionization catalytic reaction in a thermal analysis chamber (51); the carrier gas enters the thermal analysis chamber (51) from the carrier gas inlet (53) to be mixed with the reaction product gas, and the mixed gas is sent into an analysis and detection instrument for detection.

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