A cage type dual photoionization source mass spectrometry device based on molecular beam sampling

Abstract

The utility model provides a kind of cage type double photoionization source mass spectrometer based on molecular beam sampling, including photoionization unit, photoionization unit includes first casing, vacuum ultraviolet lamp and synchrotron radiation light connecting part;First casing is hollow structure with first inner cavity, photoionization region is formed in first inner cavity;First casing is equipped with the connecting hole being communicated with first inner cavity, the axis of connecting hole passes through photoionization region;Vacuum ultraviolet lamp is arranged in first inner cavity, and vacuum ultraviolet light generated by vacuum ultraviolet lamp can be transmitted to photoionization region;Synchrotron radiation light connecting part is at least partially set in first casing outside, and is connected at connecting hole.It is thus that double photoionization source mass spectrometer can utilize synchrotron radiation light to realize the photoionization of sample to be measured, and when synchrotron radiation light is unavailable, the photoionization of sample to be measured can be realized using the vacuum ultraviolet lamp, to alleviate the problem that cannot meet experimental demand due to synchrotron radiation light machine tense.

Description

Technical Field

[0001] This invention belongs to the field of analytical chemistry technology, specifically relating to a cage-type dual photoionization source mass spectrometer based on molecular beam sampling. Background Technology

[0002] Photoionization mass spectrometry (PMS) is a commonly used analytical method. Synchrotron radiation sources are a common light source in PMS, characterized by high light intensity, good collimation, wide wavelength coverage, and continuously adjustable energy.

[0003] Synchrotron radiation photoionization mass spectrometry (SPS) facilities have long served a wide range of diverse experimental needs, resulting in extremely high light consumption. However, synchrotron radiation sources require regular maintenance and adjustments, leading to reduced availability and consequently decreasing the online time of the SPS. Utility Model Content

[0004] The purpose of this invention is to provide a cage-type dual photoionization source mass spectrometer based on molecular beam sampling, which aims to achieve sample photoionization using other light sources when synchrotron radiation sources are unavailable.

[0005] To achieve the above objectives, this utility model provides a dual photoionization source mass spectrometry device, including a photoionization unit, wherein the photoionization unit includes: The first housing is a hollow structure with a first inner cavity, in which a photoionization region is formed; the first housing is provided with a connection hole communicating with the first inner cavity, and the axis of the connection hole passes through the photoionization region; A vacuum ultraviolet lamp is disposed in the first inner cavity, the axis of the vacuum ultraviolet lamp passing through the photoionization region, and the vacuum ultraviolet light generated by the vacuum ultraviolet lamp is transmitted along the axis of the vacuum ultraviolet lamp and incident on the photoionization region; and, A synchrotron radiation optical connection portion is at least partially disposed outside the first housing and connected to the connection hole.

[0006] Optionally, the axis of the connecting hole intersects with the axis of the vacuum ultraviolet lamp.

[0007] Optionally, the synchrotron radiation optical connection part includes a transfer tube and a light transmission tube. The transfer tube is disposed outside the first housing and connected to the first housing. The transfer tube is disposed corresponding to the connection hole. A portion of the light transmission tube passes through the transfer tube and another portion passes through the connection hole and extends into the first inner cavity.

[0008] Optionally, the photoionization unit further includes a cage electrode disposed in the first inner cavity; the cage electrode is a hollow structure with a second inner cavity, the second inner cavity constituting the photoionization region; the cage electrode is provided with a first through hole, a second through hole, a third through hole, and a fourth through hole communicating with the second inner cavity; the first through hole and the second through hole are arranged opposite to each other on the axis of the vacuum ultraviolet lamp, the first through hole being closer to the vacuum ultraviolet lamp than the second through hole; the third through hole and the fourth through hole are arranged opposite to each other on the axis of the connecting hole, the third through hole being closer to the connecting hole than the fourth through hole.

[0009] Optionally, the photoionization region has a sample inlet and a sample outlet opposite each other in the axial direction of the dual photoionization source mass spectrometer, and the axial direction of the dual photoionization source mass spectrometer is perpendicular to the axis of the connecting hole and the axis of the vacuum ultraviolet lamp. The dual photoionization source mass spectrometer further includes a reactor connection unit, which is at least partially disposed in the first inner cavity and connected to the first housing; the reactor connection unit is located on the side of the sample inlet away from the sample outlet; A molecular pump interface is provided on the wall of the first housing extending axially along the dual photoionization source mass spectrometer, and the molecular pump interface is in communication with the first inner cavity.

[0010] Optionally, the reactor connection unit includes a second shell and a sampling positioning component. The second shell is at least partially disposed in the first inner cavity and connected to the first shell. The second shell is a hollow structure with a third inner cavity. The wall of the second shell located in the first inner cavity and facing the sample inlet has a seventh through hole coaxial with the sample inlet. The sampling positioning component is at least partially disposed in the third inner cavity and connected to the second shell. The sampling positioning component is correspondingly disposed to the seventh through hole.

[0011] Optionally, the axial direction of the molecular pump interface is perpendicular to the axial direction of the dual photoionization source mass spectrometer; the photoionization unit has a first side and a second side opposite to each other in the axial direction of the molecular pump interface; the second housing includes a first segment and a second segment arranged and connected along the axial direction of the dual photoionization source mass spectrometer, the first segment being closer to the cage electrode than the second segment; on the first side, the outer surface of the second housing is disposed bordering the cavity wall of the first inner cavity; on the second side, the distance from the outer surface of the first segment to the cavity wall of the first inner cavity is greater than the distance from the outer surface of the second segment to the cavity wall of the first inner cavity, and the outer surface of the second segment is disposed adjacent to the cavity wall of the first inner cavity; The molecular pump interface is located on the second side and corresponds to the first segment.

[0012] Optionally, the diameter of the molecular pump interface is 100mm to 200mm.

[0013] Optionally, the sampling positioning element includes a first positioning body and a second positioning body. The first positioning body is at least partially disposed in the third inner cavity and connected to the second housing. An eighth through hole is formed on the first positioning body, and the eighth through hole is coaxially arranged with the seventh through hole. The second positioning body is disposed in the third inner cavity and includes a positioning sleeve. The positioning sleeve is sleeved on the outer periphery of the first positioning body and connected to the second housing.

[0014] Optionally, a portion of the first positioning body passes through the seventh through hole and another portion extends into the third inner cavity; the first positioning body includes a plurality of sub-positioning bodies, which are arranged at intervals around the axis of the seventh through hole; the space between the plurality of sub-positioning bodies constitutes at least a portion of the eighth through hole.

[0015] To achieve the above objectives, this utility model also provides another photoionization mass spectrometry device, including a photoionization unit and a reactor connection unit; the photoionization unit includes a first housing, the first housing being a hollow structure with a first inner cavity, in which a photoionization region is formed, the photoionization region having a sample inlet and a sample outlet opposite each other in the axial direction of the photoionization mass spectrometry device; the reactor connection unit is at least partially disposed in the first inner cavity and connected to the first housing; the reactor connection unit is located on the side of the sample inlet away from the sample outlet; A molecular pump interface is provided on the wall of the first housing extending along the axial direction of the photoionization mass spectrometer, and the molecular pump interface is in communication with the first inner cavity.

[0016] Optionally, the reactor connection unit includes a second shell and a sampling positioning component. The second shell is at least partially disposed in the first inner cavity and connected to the first shell. The second shell is a hollow structure with a third inner cavity. The wall of the second shell located in the first inner cavity and facing the sample inlet has a seventh through hole coaxial with the sample inlet. The sampling positioning component is at least partially disposed in the third inner cavity and connected to the second shell. The sampling positioning component is correspondingly disposed to the seventh through hole.

[0017] Optionally, the axial direction of the molecular pump interface is perpendicular to the axial direction of the photoionization mass spectrometer; the photoionization unit has a first side and a second side opposite to each other in the axial direction of the molecular pump interface; the second housing includes a first segment and a second segment arranged and connected along the axial direction of the photoionization mass spectrometer, the first segment being closer to the photoionization region than the second segment; on the first side, the outer surface of the second housing is disposed adjacent to the cavity wall of the first inner cavity; on the second side, the distance from the outer surface of the first segment to the cavity wall of the first inner cavity is greater than the distance from the outer surface of the second segment to the cavity wall of the first inner cavity, and the outer surface of the second segment is disposed adjacent to the cavity wall of the first inner cavity; The molecular pump interface is located on the second side and corresponds to the first segment.

[0018] Optionally, the first inner cavity includes a third segment and a fourth segment connected along the axial direction of the photoionization mass spectrometer, the cross-section of the third segment is smaller than the cross-section of the fourth segment, the third segment and the fourth segment are flush on the second side, and the fourth segment protrudes from the third segment on the first side; the photoionization region is formed within the third segment; The cross-section of the first segment is smaller than that of the second segment, and the first segment, the second segment, and the fourth segment are coaxially arranged; a portion of the first segment is disposed in the third segment and another portion is disposed in the fourth segment, and the second segment is disposed in the fourth segment; Optionally, the first inner cavity includes a target segment, and the photoionization region is formed within the target segment; the cross-section of the first segment is smaller than the cross-section of the second segment, the first segment and the second segment are aligned on the first side, the second segment protrudes from the first segment on the second side, and the second segment and the target segment are coaxially arranged.

[0019] Optionally, the diameter of the molecular pump interface is 100mm to 200mm.

[0020] Optionally, the sampling positioning element includes a first positioning body and a second positioning body. The first positioning body is at least partially disposed in the third inner cavity and connected to the second housing. An eighth through hole is formed on the first positioning body, and the eighth through hole is coaxially arranged with the seventh through hole. The second positioning body is disposed in the third inner cavity and includes a positioning sleeve. The positioning sleeve is sleeved on the outer periphery of the first positioning body and connected to the second housing.

[0021] Optionally, a portion of the first positioning body passes through the seventh through hole and another portion extends into the third inner cavity; the first positioning body includes a plurality of sub-positioning bodies, which are arranged at intervals around the axis of the seventh through hole; the space between the plurality of sub-positioning bodies constitutes at least a portion of the eighth through hole.

[0022] Compared with existing technologies, the cage-type dual photoionization source mass spectrometer based on molecular beam sampling of this invention has the following advantages: The aforementioned dual-photoionization-source mass spectrometry device includes a photoionization unit, which comprises a first housing, a vacuum ultraviolet lamp, and a synchrotron radiation connection. The first housing is a hollow structure with a first inner cavity, in which a photoionization region is formed. The first housing has a connection hole communicating with the first inner cavity, the axis of which passes through the photoionization region. The vacuum ultraviolet lamp is disposed within the first inner cavity, its axis passing through the photoionization region, and the vacuum ultraviolet light generated by the lamp is transmitted along its axis and passes through the photoionization region. The synchrotron radiation connection is at least partially disposed outside the first housing and connected to the second connection hole. Therefore, the dual-photoionization-source mass spectrometry device can utilize synchrotron radiation to achieve photoionization of the sample, or utilize the vacuum ultraviolet lamp to achieve photoionization when synchrotron radiation is unavailable, thus alleviating the problem of insufficient time for synchrotron radiation testing and the inability to meet experimental requirements.

[0023] Furthermore, the photoionization region has a sample inlet and a sample outlet opposite each other along the axial direction of the dual photoionization source mass spectrometer; the axial direction of the dual photoionization source mass spectrometer is perpendicular to the axis of the connecting hole and the axis of the vacuum ultraviolet lamp; the dual photoionization source mass spectrometer also includes a reactor connection unit, which is at least partially disposed in the first inner cavity and located on the side of the sample inlet away from the sample outlet; the reactor connection unit is connected to the first housing; a molecular pump interface is provided on the wall of the first housing extending along the axial direction of the dual photoionization source mass spectrometer, and the molecular pump interface communicates with the first inner cavity; by disposing of the reactor connection unit at least partially in the first inner cavity, the axial dimensions of the first inner cavity and the first housing of the dual photoionization source mass spectrometer are increased, thereby allowing the molecular pump interface to be set larger, so that the dual photoionization source mass spectrometer can be used in conjunction with a molecular pump with a high pumping speed, while utilizing the space occupied by the reactor connection unit in the first inner cavity reduces the empty space in the first inner cavity, thereby improving the vacuuming speed and effect of the first inner cavity. Attached Figure Description

[0024] The accompanying drawings are provided to better understand this utility model and do not constitute an undue limitation on it. Wherein: Figure 1 This is a schematic diagram of the structure of a dual photoionization source mass spectrometer according to an embodiment of the present invention; Figure 2 This is a simplified structural diagram of the dual photoionization source mass spectrometer provided by the present invention according to an alternative embodiment; Figure 3 yes Figure 1 A partial structural schematic diagram of the dual photoionization source mass spectrometer shown; Figure 4 This is a schematic diagram of the structure of the first positioning body of the dual photoionization source mass spectrometer provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of the structure of a photoionization mass spectrometry device in the prior art.

[0025] [The following are explanations of the reference numerals in the attached diagram]: 10 - Dual photoionization source mass spectrometer, 10' - Photoionization mass spectrometer, 100, 100' - Photoionization unit, 101 - First side, 102 - Second side, 110, 110' - First housing, 111 - First inner cavity, 1111 - First segment, 1112 - Second segment, 112, 112' - Molecular pump interface, 120 - Vacuum ultraviolet lamp, 130 - Synchrotron radiation connection Part, 131-Adapter tube, 132-Light transmission tube, 140-Cage electrode, 141-Second inner cavity, 142-Fifth through hole, 143-Sixth through hole, 144-First through hole, 145-Third through hole, 146-Fourth through hole, 150-Molecular beam focusing tube, 151-Fourth inner cavity, 160, 160'-Molecular beam sampling cone, 161-Sampling channel, 170-Focusing electrode plate, 171-Ninth through hole, 2 00-Ion introducer, 300-Mass analyzer, 400-Reactor connection unit, 410-Second shell, 4101-First pore section, 4102-Second pore section, 4103-Third section, 4104-Fourth section, 411-Third inner cavity, 412-Side wall, 413-First end wall, 414-Second end wall, 420-Sampling positioning element, 421-First positioning body, 4211-Eighth through hole, 42 12-First joint, 4213-Sub-positioning body, 4213a-Fifth segment, 4213b-Sixth segment, 4213c-Third step surface, 422-Second positioning body, 4221-Positioning sleeve, 4223-Second joint, 4224-Third joint, 430-Jointing tube, 500-Sealing element, 20-Docking device, 21-Light outlet, 30-Reactor, 31-Inner tube, 32-Outer tube. Detailed Implementation

[0026] The following specific examples illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. This utility model can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of this utility model. It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of this utility model. Therefore, the drawings only show components related to this utility model and are not drawn according to the actual number, shape, and size of the components in implementation. In actual implementation, the type, quantity, and proportion of each component can be arbitrarily changed, and the component layout may also be more complex.

[0027] Furthermore, while each embodiment described below possesses one or more technical features, this does not imply that users of this utility model must simultaneously implement all technical features in any embodiment, or can only separately implement some or all technical features in different embodiments. In other words, provided it is feasible, those skilled in the art can selectively implement some or all technical features in any embodiment, or selectively implement a combination of some or all technical features in multiple embodiments, based on the disclosure of this utility model and depending on design specifications or implementation requirements, thereby increasing the flexibility in implementing this utility model.

[0028] As used herein, the singular forms “a,” “an,” and “the” include plural objects, and the plural form “a plurality” includes two or more objects, unless otherwise expressly indicated. As used herein, the term “or” is generally used to include the meaning of “and / or,” unless otherwise expressly indicated, and the terms “install,” “connect,” and “link” should be interpreted broadly, for example, as a fixed connection, a detachable connection, or an integral connection. Connections can be mechanical or electrical. Connections can be direct or indirect through an intermediate medium, and can represent internal communication between two elements or an interaction between two elements. Relational terms such as “first,” “second,” etc., are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations, nor do they indicate relative importance or implicitly specify the number of indicated technical features. Those skilled in the art will understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0029] To make the objectives, advantages, and features of this utility model clearer, the following detailed description is provided in conjunction with the accompanying drawings. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to conveniently and clearly illustrate the objectives of the embodiments of this utility model. The same or similar reference numerals in the drawings represent the same or similar parts.

[0030] like Figure 1 As shown, the dual photoionization source mass spectrometer 10 provided in some embodiments of this utility model includes a photoionization unit 100, which includes a first housing 110, a vacuum ultraviolet lamp 120, and a synchrotron radiation connection part 130. The first housing 110 is a hollow structure with a first inner cavity 111, in which a photoionization region (not shown in the figure) is formed. The first housing 110 is provided with a connection hole (not shown in the figure) communicating with the first inner cavity 111. The axis of the connection hole passes through the photoionization region. The vacuum ultraviolet lamp 120 is disposed in the first inner cavity 111 and remains relatively stationary with respect to the first housing 110. The axis of the vacuum ultraviolet lamp 120 passes through the photoionization region, and the vacuum ultraviolet light generated by the vacuum ultraviolet lamp 120 is transmitted along the axis of the vacuum ultraviolet lamp 120 and incident on the photoionization region. The synchrotron radiation light connection part 130 is at least partially disposed outside the first housing 110 and connected to the connection hole so that the synchrotron radiation light generated by the synchrotron radiation light source can be incident on the photoionization region.

[0031] The dual photoionization source mass spectrometer 10 selectively photoionizes sample molecules located in the photoionization region using either vacuum ultraviolet light or synchrotron radiation during operation. In other words, the dual photoionization source mass spectrometer 10 can operate based on the vacuum ultraviolet light emitted by the vacuum ultraviolet lamp 120 during maintenance and debugging of the synchrotron radiation source or under other circumstances, thereby increasing the availability of the dual photoionization source mass spectrometer 10 and meeting a large number of experimental needs.

[0032] In an exemplary embodiment, the axis of the connecting hole and the axis of the vacuum ultraviolet lamp 120 are both perpendicular to the axis of the dual photoionization source mass spectrometer 10.

[0033] The vacuum ultraviolet lamp 120 can be kept relatively stationary with the first housing 110 in any suitable manner, such as being fixedly connected to the first housing 110, or being fixedly connected to other components (such as the second housing 410 mentioned later). This embodiment of the present invention does not limit this.

[0034] The synchrotron radiation optical connection portion 130 includes an adapter tube 131 and a light-transmitting tube 132. The adapter tube 131 is disposed outside the first housing 110 and corresponds to the connection hole. Preferably, the adapter tube 131 is coaxially arranged with the connection hole. The inner diameter of the adapter tube 131 is larger than the diameter of the connection hole. A portion of the light-transmitting tube 132 passes through the adapter tube 131, and another portion passes through the connection hole and extends into the first inner cavity 111.

[0035] Those skilled in the art will know that the synchrotron radiation source has a docking device 20 (such as...). Figure 1 As shown), a light-emitting port 21 is formed on the docking device 20. The end of the adapter tube 131 away from the first housing 110 is connected to the docking device 20, and the light-transmitting tube 132 is connected to the light-emitting port 21 so that the synchrotron radiation light is transmitted along the light-transmitting tube 132 and enters the first inner cavity 111, and then incident on the photoionization region.

[0036] The adapter tube 131 has a relatively large inner and outer diameter to facilitate connection with the docking device 20. The inner diameter of the light-transmitting tube 132 is smaller than that of the adapter tube 131, which helps to reduce the impact of the dual photoionization source mass spectrometer 10 on the vacuum environment inside the synchrotron radiation source.

[0037] like Figures 1 to 3 As shown, the photoionization unit 100 further includes a cage electrode 140, which is disposed in the first inner cavity 111 and remains relatively stationary with respect to the first housing 110. The cage electrode 140 is a hollow structure with a second inner cavity 141, which constitutes the photoionization region. The cage electrode 140 can be fixedly connected to the first housing 110, or it can be fixedly connected to other components, such as the second housing 410 described later. This embodiment of the present invention does not limit this.

[0038] Please refer to Figure 3 The cage electrode 140 is provided with a fifth through hole 142 and a sixth through hole 143 communicating with the second inner cavity 141. The fifth through hole 142 and the sixth through hole 143 are arranged opposite to each other in the axial direction of the dual photoionization source mass spectrometer 10. The fifth through hole 142 constitutes the sample inlet of the photoionization region, and the sixth through hole 143 constitutes the sample outlet of the photoionization region. In this way, the sample to be tested flows into the photoionization region through the fifth through hole 142, and the sample to be tested, after being photoionized at least partially, flows out of the photoionization region through the sixth through hole 143.

[0039] Preferably, the fifth through hole 142, the sixth through hole 143, and the second inner cavity 141 are arranged coaxially. In an optional example, the cross-section of the second inner cavity 141 perpendicular to the photoionization unit 100 is circular, and more preferably, the diameter of the sixth through hole 143 is equal to the diameter of the second inner cavity 141, and the diameter of the fifth through hole 142 is smaller than the diameter of the sixth through hole 143, for example, half the diameter of the sixth through hole 143.

[0040] like Figure 3 As shown, the cage electrode 140 is further provided with a first through hole 144, a second through hole (not shown), a third through hole 145, and a fourth through hole 146 communicating with the second inner cavity 141. The first through hole 144 and the second through hole are arranged opposite to each other on the axis of the vacuum ultraviolet lamp 120, preferably coaxially, and the first through hole 144 is closer to the vacuum ultraviolet lamp 120 than the second through hole. The third through hole 145 and the fourth through hole 146 are arranged opposite to each other on the axis of the connecting hole, and the third through hole 145 is closer to the connecting hole than the fourth through hole 146. Preferably, the third through hole 145, the fourth through hole 146, and the light-transmitting tube 132 are arranged coaxially.

[0041] The vacuum ultraviolet light is incident on the photoionization region through the first through-hole 144 and exits the photoionization region through the second through-hole. The purpose of providing the second through-hole is to prevent the vacuum ultraviolet light from incident on the inner wall of the cage electrode 140, which could cause photoelectric effect, photoelectron overflow, or other problems. The synchrotron radiation is incident on the photoionization region through the third through-hole 145 and exits the photoionization region through the fourth through-hole 146. The purpose of providing the fourth through-hole 146 is to prevent the vacuum ultraviolet light from incident on the inner wall of the cage electrode 140, which could cause photoelectric effect, photoelectron overflow, or other problems.

[0042] The apertures of the first through-hole 144, the second through-hole, the third through-hole 145, and the fourth through-hole 146 should be appropriate. If the apertures of the first through-hole 144 and the second through-hole are too small, they will block the synchrotron radiation. If the apertures of the third through-hole 145 and the fourth through-hole 146 are too small, they will block the synchrotron radiation. If the apertures of the first through-hole 144, the second through-hole, the third through-hole 145, and the fourth through-hole 146 are too large, they will cause excessive carrier gas and leakage of the sample to be tested. Preferably, the shape of the first through-hole 144 and the second through-hole is the same as the shape of the vacuum ultraviolet light spot, and the size is adapted to the size of the vacuum ultraviolet light spot; and preferably, the shape of the third through-hole 145 and the fourth through-hole 146 is the same as the shape of the synchrotron radiation spot, and the size is adapted to the size of the synchrotron radiation spot.

[0043] In practice, the vacuum ultraviolet light spot is circular, and the diameter of the spot on the first preset plane is approximately 5 mm. The first preset plane is located at the end of the first through-hole furthest from the second through-hole and is perpendicular to the axis of the first through-hole 144. Accordingly, the first through-hole 144 and the second through-hole are circular holes, and their diameters are slightly larger than 5 mm. The synchrotron radiation light spot is rectangular, with dimensions of approximately 4 mm × 8 mm. Accordingly, the third through-hole 145 and the fourth through-hole 146 are rectangular holes, and their cross-sectional dimensions are slightly larger than 4 mm × 8 mm.

[0044] The photoionization region should not be too large to avoid low concentration of the sample under test due to excessive photoionization, resulting in fewer ions generated by ionization. Preferably, the axis of the connecting hole, the axis of the vacuum ultraviolet lamp 120, and the axis of the second inner cavity 141 intersect at one point to reduce the photoionization region. Adapted to the spot size of the synchrotron radiation and the spot size of the vacuum ultraviolet light, the diameter of the cross-section of the second inner cavity 141 perpendicular to the axis of the dual photoionization source mass spectrometer 10 can be 15mm to 23mm, for example, 18mm, and the axial dimension of the second inner cavity 141 in the dual photoionization source mass spectrometer is 13mm to 17mm, for example, 15mm.

[0045] Those skilled in the art will understand that a molecular pump interface 112, communicating with the first inner cavity 111, is also provided on the wall of the first housing 110 extending along the axial direction of the dual photoionization source mass spectrometer 10. The axial direction of the molecular pump interface 112 can be perpendicular to the axial direction of the dual photoionization source mass spectrometer 10. The molecular pump interface 112 is used to connect to a molecular pump, which is used to evacuate the first inner cavity 111 to maintain the first inner cavity 111 at a set vacuum level. From the perspective of facilitating the arrangement of the molecular pump interface 112, the connection hole, and the vacuum ultraviolet lamp 120, it is preferable that the axis of the connection hole is perpendicular to the axis of the vacuum ultraviolet lamp 120. The axis of the molecular pump interface 112 can be parallel to the axis of the connection hole or parallel to the axis of the vacuum ultraviolet lamp 120.

[0046] Optionally, the photoionization unit 100 further includes a molecular beam focusing cylinder 150, a molecular beam sampling cone 160, and several focusing electrode plates 170.

[0047] The molecular beam focusing cylinder 150 is disposed in the first inner cavity 111 and remains relatively stationary with respect to the first housing 110. The molecular beam focusing cylinder 150 is located on the side of the fifth through hole 142 of the cage electrode 140 away from the sixth through hole 143. The molecular beam sampling cone 160 is disposed on the side of the molecular beam focusing cylinder 150 away from the cage electrode 140 and is preferably connected to the molecular beam focusing cylinder 150. The molecular beam focusing cylinder 150 has a fourth inner cavity 151 extending through the axis of the dual photoionization source mass spectrometer 10. The molecular beam sampling cone 160 has a sampling channel 161 extending through the axis of the dual photoionization source mass spectrometer 10. The cross-section of the sampling channel 161 perpendicular to the axis of the dual photoionization source mass spectrometer 10 increases in the direction close to the cage electrode 140, and preferably the sampling channel 161, the fourth inner cavity 151, and the fifth through hole 142 are arranged coaxially. The sample to be tested flows sequentially into the photoionization region through the sampling channel 161, the fourth inner cavity 151, and the fifth through-hole 142. By setting the molecular beam sampling cone 160, the sample to be tested can enter the first inner cavity 111 in the form of a molecular beam. By setting the molecular beam focusing cylinder 150, the sample to be tested in the form of a molecular beam can be focused, increasing the molecular density of the sample to be tested entering the photoionization region through the fifth through-hole 142.

[0048] A plurality of focusing electrode plates 170 are disposed in the first inner cavity 111 and connected to the first housing 110. The plurality of focusing electrode plates 170 are located on the side of the cage electrode 140 away from the molecular beam focusing cylinder 150, and are sequentially spaced along the axial direction of the dual photoionization source mass spectrometer 10. Each focusing electrode plate 170 is provided with a ninth through hole 171. All ninth through holes 171 are coaxially arranged with the sixth through hole 143, and the diameter of all ninth through holes 171 is smaller than the diameter of the sixth through hole 143. Furthermore, the diameter of the ninth through hole 171 on the focusing electrode plate 170 farther from the cage electrode 140 is smaller.

[0049] Those skilled in the art will understand that the dual photoionization source mass spectrometer 10 further includes an ion introducer 200 and a mass analyzer 300. The photoionization unit 100, the ion introducer 200, and the mass analyzer 300 are arranged sequentially along the axial direction of the dual photoionization source mass spectrometer 10. The ion introducer 200 is located on the side of all the focusing electrode plates 170 away from the cage electrode 140, and the mass analyzer 300 is located on the side of the ion introducer 200 away from all the focusing electrode plates 170. The sample to be tested flowing out of the photoionization region flows into the ion introducer 200 and the mass analyzer 300 after passing through the ninth through-hole 171 of all the focusing electrode plates 170 for mass analysis.

[0050] When using the dual photoionization source mass spectrometer 10 to perform in-situ online analysis of some reactions, such as... Figure 1 As shown, the dual photoionization source mass spectrometer 10 is connected to the outlet of the reactor 30 used to perform the reaction, so that the reaction products generated by the reaction directly enter the dual photoionization source mass spectrometer 10. It can be understood that the reaction products here are the test samples mentioned above.

[0051] In practice, the distance between the outlet of the reactor 30 and the sample inlet of the photoionization zone should be as small as possible, thereby minimizing the transport path of the sample to be tested. A shorter transport path helps reduce sample loss during transport and improves the reliability and accuracy of the analytical results of the dual photoionization source mass spectrometer 10.

[0052] Those skilled in the art will know that, with the free space in the first inner cavity 111 remaining unchanged, the greater the pumping speed of the molecular pump, the shorter the time required for the first inner cavity 111 to reach the set vacuum level, and the greater the pumping speed of the molecular pump, the larger the size of the corresponding molecular pump interface 112.

[0053] Preferably, such as Figure 1 and Figure 2As shown, the molecular beam sampling cone 160 is disposed in the first inner cavity 111, and the dual photoionization source mass spectrometer 10 further includes a reactor connection unit 400. The reactor connection unit 400 is at least partially disposed in the first inner cavity 111 and connected to the first housing 110. The reactor connection unit 400 is located on the side of the sample inlet away from the sample outlet. When the dual photoionization source mass spectrometer 10 is connected to the reactor 30, the outlet end of the reactor 30 extends into the photoionization unit 100 and is connected to the reactor connection unit 400. The advantage of this approach is that, while minimizing the distance between the outlet of the reactor 30 and the sample inlet of the photoionization zone, it also increases the axial dimension of the first housing 110 in the dual photoionization source mass spectrometer 10. This allows for the installation of a larger molecular pump interface 112 on the first housing 110, enabling the dual photoionization source mass spectrometer 10 to be used in conjunction with a molecular pump with a higher pumping speed. Simultaneously, the reactor connection unit 400 occupies a portion of the space in the first inner cavity 111, reducing the empty space in the first inner cavity 111 and thereby improving the vacuuming speed and efficiency of the molecular pump.

[0054] In this embodiment of the invention, the diameter of the molecular pump interface 112 can be increased to 100mm to 200mm. Figure 5 A prior art photoionization mass spectrometry device 10' is shown. The photoionization mass spectrometry device 10' includes a photoionization unit 100', which uses synchrotron radiation with a spot size of 4mm × 8mm to perform photoionization. The photoionization mass spectrometry device 10' includes a first housing 110' and a molecular beam sampling cone 160'. A photoionization region is formed within the first housing 110', and the molecular beam sampling cone 160' is correspondingly positioned to introduce the sample to be tested into the photoionization region in the form of an ultrasonic molecular beam. The molecular beam sampling cone 160' is at least partially disposed outside the first housing 110', such that when the photoionization mass spectrometry device 10' is used in conjunction with a reactor 30', the reactor 30' is completely located outside the photoionization unit 100'. The first housing 110' of this photoionization mass spectrometry device 10' has a small axial dimension, and correspondingly, the diameter of the molecular pump interface 112' is also small, only about 35mm.

[0055] The reactor connection unit 400 includes a second housing 410 and a sampling positioning member 420. The second housing 410 is at least partially disposed in the first inner cavity 111 and connected to the first housing 110. The second housing 410 is a hollow structure with a third inner cavity 411. The second housing 410 is located in the first inner cavity 111 and has a seventh through hole (not shown in the figure) extending through the axial direction of the dual photoionization source mass spectrometer 10 on its wall facing the sample inlet. Preferably, the seventh through hole is coaxial with the sample inlet. The sampling positioning member 420 is at least partially disposed in the third inner cavity 411 and is positioned corresponding to the seventh through hole. The outlet end of the reactor 30 is connected to the sampling positioning member 420 such that the outlet end of the reactor 30 is coaxial or substantially coaxial with the sample inlet and communicates with the sample inlet through the sampling channel 161 and the fourth inner cavity 151.

[0056] In an alternative example, the first housing 110 is open at the end of the molecular beam sampling cone 160 located away from the molecular beam focusing cylinder 150, forming an opening (not shown in the figure). A second housing 410 is partially disposed within the first inner cavity 111, connected to the first housing 110, and closes the opening. It should be understood that a seal 500 is also provided between the second housing 410 and the first housing 110 to prevent air leakage at the connection point.

[0057] The second housing 410 more specifically includes a side wall 412, a first end wall 413, and a second end wall 414. The first end wall 413 and the second end wall 414 are arranged opposite each other in the axial direction of the dual photoionization source mass spectrometer 10, and are respectively connected to the two opposite ends of the side wall 412 in the axial direction of the dual photoionization source mass spectrometer 10, such that the side wall 412, the first end wall 413, and the second end wall 414 enclose and form the third inner cavity 411. A portion of the side wall 412 and the first end wall 413 are disposed within the first inner cavity 111, and the second end wall 414 is disposed outside the first housing 110. The sealing element 500 is provided between the outer surface of the side wall 412 and the inner surface of the first housing 110. The first end wall 413 constitutes the wall of the second housing 410 located in the first inner cavity 111 and facing the sample inlet, and the first end wall 413 is provided with the seventh through hole.

[0058] Please refer to Figure 1In an optional example, the reactor 30 includes an inner tube 31 and an outer tube 32 fitted around a portion of the outer periphery of the inner tube 31. The inner tube 31 is used to load reactants, and the reaction occurs within the inner tube 31. One end of the reactor 30 passes through the second end wall 414 and extends into the third inner cavity 411, wherein the end of the inner tube 31 located in the third inner cavity 411 constitutes the outlet end of the reactor 30. It is understood that the outer surface of the outer tube 414 is sealingly connected to the second end wall 414.

[0059] The sampling positioning element 420 includes a first positioning body 421 and a second positioning body 422. The first positioning body 421 is at least partially disposed in the third inner cavity 411 and connected to the second housing 410. An eighth through hole 4211 (e.g., ...) is formed on the first positioning body 421. Figure 4 As shown in the diagram, the eighth through hole 4211 is coaxially arranged with the seventh through hole. The second positioning body 422 is disposed in the third inner cavity 411 and includes a positioning sleeve 4221, which is sleeved on the outer periphery of the first positioning body 421 and connected to the second housing 410. The outer tube 32 is used to partially pass through the positioning sleeve 4221. The inner tube 31 is used to partially pass through the eighth through hole 4211. In some examples, the molecular beam focusing tube 150 is partially located in the seventh through hole, the molecular beam sampling cone 160 partially passes through the eighth through hole 4211, and further, the molecular beam sampling cone 160 also partially passes through the lumen of the inner tube 31.

[0060] Optionally, the seventh through hole is a stepped hole, and includes a first hole section 4101 and a second hole section 4102 connected along its own axial direction (e.g., ...). Figure 3 As shown in the figure, the first hole segment 4101, the second hole segment 4102, and the third hole segment are arranged in a direction away from the cage electrode 140, and the diameters of the first hole segment 4101, the second hole segment 4102, and the third hole segment decrease sequentially, so that the junction of the first hole segment 4101 and the second hole segment 4102 forms a first stepped surface (not shown in the figure), and the junction of the second hole segment 4102 and the third hole segment forms a second stepped surface (not shown in the figure).

[0061] like Figure 3 and Figure 4As shown, the first positioning body 421 includes a first joint 4212 and a plurality of sub-positioning bodies 4213. The first joint 4212 is disposed within the first hole segment 4101 and abuts against and connects to the first stepped surface. The first joint 4212 is provided with a through hole (not shown in the figure) extending through the axis of the dual photoionization source mass spectrometer 10, and the through hole is preferably coaxially arranged with the seventh through hole. The plurality of sub-positioning bodies 4213 are disposed on the side of the first joint 4212 away from the cage electrode 140, and the plurality of sub-positioning bodies 4213 are arranged at intervals around the axis of the through hole, for example, at equal intervals. The space between the plurality of sub-positioning bodies 4213 and the through hole together constitute the eighth through hole 4211. The sub-positioning body 4213 includes a fifth segment 4213a and a sixth segment 4213b arranged and connected in a direction away from the first connecting body 4212. The distance from the outer surface of the fifth segment 4213a to the axis of the eighth through hole 4211 is greater than the distance from the outer surface of the sixth segment 4213b to the axis of the eighth through hole 4211, such that the outer surface of the sub-positioning body 4213 forms a third stepped surface 4213c at the junction of the fifth segment 4213a and the sixth segment 4213b. The fifth segment 4213a is disposed within the second hole segment 4102, and the third stepped surface 4213c abuts against the second stepped surface. One end of the sixth segment 4213b away from the fifth segment 4213a passes through the third hole segment and extends into the third inner cavity 411.

[0062] Additionally, the molecular beam focusing tube 150 may be partially disposed within the first aperture section 4101. The end of the molecular beam sampling cone 160 away from the molecular beam focusing tube 150 passes through the through-hole and extends into the space between the plurality of sub-positioning bodies 4213.

[0063] The second positioning body 422 further includes a first engaging portion 4222 and a second engaging portion 4223. The first engaging portion 4222 is disposed on the outer surface of the positioning sleeve 4221 at the end facing the cage electrode 140 and extends in a direction away from the axis of the positioning sleeve 4221, and is connected to the second housing 410. The second engaging portion 4223 is disposed on the inner surface of the positioning sleeve 4222 at the end away from the cage electrode 140 and extends in a direction close to the axis of the positioning sleeve 4221. The outer tube 32 partially extends into the positioning sleeve 4221 and connects to the second engaging portion 4223. It should be understood that the inner diameter of the second engaging portion 4222 is greater than the distance from the outer surface of the sixth segment 4213b to the axis of the eighth through hole 4211.

[0064] Optionally, the second positioning body 422 further includes a third engaging portion 4224, which is an engaging sleeve. The engaging sleeve is coaxially arranged with the positioning sleeve 4221 and connected to the end of the second engaging portion 4223 facing the cage electrode 140. The outer tube 32 also partially passes through the engaging sleeve and is connected to the engaging sleeve.

[0065] Furthermore, the reactor connection unit 400 also includes a connecting tube 430, one end of which penetrates the side wall of the positioning sleeve 4221, allowing the lumen of the connecting tube 430 to communicate with the lumen of the inner tube body 31 through the gap between the positioning sleeve 4221 and the sixth segment 4213b of the two adjacent sub-positioning bodies 4213. The other end of the connecting tube 430 passes through the second end wall 414 and extends to the outside of the dual photoionization source mass spectrometer 10. In some cases, the end of the connecting tube 430 outside the dual photoionization source mass spectrometer 10 is connected to a vacuum device. In other cases, the end of the connecting tube 430 outside the dual photoionization source mass spectrometer 10 is used in conjunction with another type of mass spectrometry, such as electron impact ionization mass spectrometry, to achieve the effect of simultaneously detecting and analyzing different substances in the sample.

[0066] Further, the photoionization unit 100 has a first side 101 and a second side 102 axially opposite to each other at the molecular pump interface 112. The second housing 410 has a first segment 4103 and a second segment 4104 arranged and connected along the axial direction of the dual photoionization source mass spectrometer device 10, wherein the first segment 4103 is closer to the cage electrode 140 than the second segment 4104. The second segment 4104 protrudes from the first segment 4103 on the second side 102. On the first side 101, the outer surface of the second housing 410 is disposed adjacent to the cavity wall of the first inner cavity 111, and on the second side 102, the outer surface of the second segment 4104 is disposed adjacent to the cavity wall of the first inner cavity 111. The distance from the outer surface of the first segment 4103 to the cavity wall of the first inner cavity 111 is greater than the distance from the outer surface of the second segment 4104 to the cavity wall of the first inner cavity 111. The molecular pump interface 112 is disposed on the second side 102 and corresponds to the first segment 4103. This arrangement allows the reactor connection unit 400 to occupy more space in the first inner cavity 111, thereby reducing the empty space in the first inner cavity 111, while also ensuring sufficient clearance between the molecular pump interface 112 and the second housing 410 to ensure that the molecular pump can effectively draw gas from the first inner cavity 111.

[0067] Specifically, in an optional example, such as Figure 1 As shown, the first inner cavity 111 includes a third segment 1111 and a fourth segment 1112 arranged and connected along the axial direction of the dual photoionization source mass spectrometer 10. The cross-section of the third segment 1111 perpendicular to the axial direction of the dual photoionization source mass spectrometer 10 is smaller than the cross-section of the fourth segment 1112 perpendicular to the axial direction of the dual photoionization source mass spectrometer 10. The third segment 1111 and the fourth segment 1112 are eccentrically arranged such that the fourth segment 1112 and the third segment 1111 are aligned on the first side 101, and the fourth segment 1112 protrudes from the third segment 1111 on the second side 102. The cage electrode 140 is disposed on the third segment 1111 such that the photoionization region is located in the third segment 1111. The cross-section of the first segment 4103 perpendicular to the axial direction of the dual photoionization source mass spectrometer 10 is smaller than the cross-section of the second segment 4104 perpendicular to the axial direction of the dual photoionization source mass spectrometer 10, and the first segment 4103, the second segment 4104, and the fourth segment 1112 are arranged coaxially. A portion of the first segment 4103 is located in the third segment 1111, and another portion is located in the fourth segment 1112, while the second segment 4104 is located in the fourth segment 1112. Furthermore, in this case, it is preferable that the axis of the molecular pump interface 112 intersects the axis of the fourth segment 1112. Alternatively, such as Figure 2 As shown, the cross-section of the third segment 1111 perpendicular to the axial direction of the dual photoionization source mass spectrometer 10 is the same as the cross-section of the fourth segment 1112 perpendicular to the axial direction of the dual photoionization source mass spectrometer 10. The third segment 1111 and the fourth segment 1112 are coaxially arranged. In this embodiment, the region where the third segment 1111 and the fourth segment 1112 are located can be referred to as the target segment. The cross-section of the first segment 4103 perpendicular to the axial direction of the dual photoionization source mass spectrometer 10 is smaller than the cross-section of the second segment 4104 perpendicular to the axial direction of the dual photoionization source mass spectrometer 10. The first segment 4103 and the second segment 4104 are eccentrically arranged, such that the first segment 4103 and the second segment 4104 are aligned on the first side 101, and the second segment 4104 protrudes from the first segment 4103 on the second side 102. The second segment 4104 is coaxially arranged with the target segment. In this case, the axis of the molecular pump interface 112 intersects the axis of the target segment.

[0068] While the present invention has been disclosed above, it is not limited thereto. Those skilled in the art can make various modifications and variations to the present invention without departing from its spirit and scope. Therefore, if such modifications and variations fall within the scope of the claims of the present invention and their equivalents, the present invention also intends to include such modifications and variations.

Claims

1. A dual photoionization source mass spectrometry device, characterized in that, Includes a photoionization unit, the photoionization unit comprising: The first housing is a hollow structure with a first inner cavity, in which a photoionization region is formed; the first housing is provided with a connection hole communicating with the first inner cavity, and the axis of the connection hole passes through the photoionization region; A vacuum ultraviolet lamp is disposed in the first inner cavity, and the axis of the vacuum ultraviolet lamp passes through the photoionization region. The vacuum ultraviolet light generated by the vacuum ultraviolet lamp is transmitted along the axis of the vacuum ultraviolet lamp and incident on the photoionization region; and, A synchrotron radiation optical connection portion is at least partially disposed outside the first housing and connected to the connection hole.

2. The dual photoionization source mass spectrometer according to claim 1, characterized in that, The axis of the vacuum ultraviolet lamp intersects the axis of the connecting hole.

3. The dual photoionization source mass spectrometry device according to claim 1, characterized in that, The synchrotron radiation optical connection part includes a transfer tube and a light transmission tube. The transfer tube is disposed outside the first housing and connected to the first housing. The transfer tube is disposed corresponding to the connection hole. A portion of the light transmission tube passes through the transfer tube and another portion passes through the connection hole and extends into the first inner cavity.

4. The dual photoionization source mass spectrometer according to claim 3, characterized in that, The photoionization unit further includes a cage electrode disposed in the first inner cavity; the cage electrode is a hollow structure with a second inner cavity, the second inner cavity constituting the photoionization region; the cage electrode is provided with a first through hole, a second through hole, a third through hole, and a fourth through hole communicating with the second inner cavity; the first through hole and the second through hole are arranged opposite to each other on the axis of the vacuum ultraviolet lamp, the first through hole being closer to the vacuum ultraviolet lamp than the second through hole; the third through hole and the fourth through hole are arranged opposite to each other on the axis of the connecting hole, the third through hole being closer to the connecting hole than the fourth through hole.

5. The dual photoionization source mass spectrometry device according to claim 4, characterized in that, The photoionization region has a sample inlet and a sample outlet that are opposite each other in the axial direction of the dual photoionization source mass spectrometer, and the axial direction of the dual photoionization source mass spectrometer is perpendicular to the axis of the connecting hole and the axis of the vacuum ultraviolet lamp. The dual photoionization source mass spectrometer further includes a reactor connection unit, which is at least partially disposed in the first inner cavity and connected to the first housing; the reactor connection unit is located on the side of the sample inlet away from the sample outlet; A molecular pump interface is provided on the wall of the first housing extending axially along the dual photoionization source mass spectrometer, and the molecular pump interface is in communication with the first inner cavity.

6. The dual photoionization source mass spectrometry device according to claim 5, characterized in that, The reactor connection unit includes a second shell and a sampling positioning component. The second shell is at least partially disposed in the first inner cavity and connected to the first shell. The second shell is a hollow structure with a third inner cavity. The wall of the second shell located in the first inner cavity and facing the sample inlet has a seventh through hole coaxial with the sample inlet. The sampling positioning component is at least partially disposed in the third inner cavity and connected to the second shell. The sampling positioning component is correspondingly disposed to the seventh through hole.

7. The dual photoionization source mass spectrometer according to claim 6, characterized in that, The axial direction of the molecular pump interface is perpendicular to the axial direction of the dual photoionization source mass spectrometer; the photoionization unit has a first side and a second side opposite to each other in the axial direction of the molecular pump interface; the second housing includes a first segment and a second segment arranged and connected along the axial direction of the dual photoionization source mass spectrometer, the first segment being closer to the cage electrode than the second segment; on the first side, the outer surface of the second housing is disposed adjacent to the cavity wall of the first inner cavity; on the second side, the distance from the outer surface of the first segment to the cavity wall of the first inner cavity is greater than the distance from the outer surface of the second segment to the cavity wall of the first inner cavity, and the outer surface of the second segment is disposed adjacent to the cavity wall of the first inner cavity; The molecular pump interface is located on the second side and corresponds to the first segment.

8. The dual photoionization source mass spectrometer according to any one of claims 5-7, characterized in that, The diameter of the molecular pump interface is 100mm to 200mm.

9. The dual photoionization source mass spectrometry device according to claim 6, characterized in that, The sampling positioning component includes a first positioning body and a second positioning body. The first positioning body is at least partially disposed in the third inner cavity and connected to the second housing. An eighth through hole is formed on the first positioning body, and the eighth through hole is coaxially arranged with the seventh through hole. The second positioning body is disposed in the third inner cavity and includes a positioning sleeve. The positioning sleeve is sleeved on the outer periphery of the first positioning body and connected to the second housing.

10. The dual photoionization source mass spectrometer according to claim 9, characterized in that, A portion of the first positioning body passes through the seventh through hole, and another portion extends into the third inner cavity; the first positioning body includes a plurality of sub-positioning bodies, which are arranged at intervals around the axis of the seventh through hole; the space between the plurality of sub-positioning bodies constitutes at least a portion of the eighth through hole.

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