Xrd-in-situ characterization apparatus and characterization method for physical adsorption

Abstract

This invention relates to the field of materials characterization, specifically providing an in-situ characterization device and method for XRD-physical adsorption, aiming to solve the problem that existing characterization devices cannot simultaneously characterize the structural state of a sample under different adsorption capacities in real time and in situ. To this end, the in-situ characterization device of this application employs a dual-chamber in-situ cell, placing the sample cell assembly in a second chamber with a controllable gas environment and temperature, thereby accurately characterizing the adsorption capacity of the sample. Simultaneously, utilizing a transmission light path formed by the first and second windows, X-rays can irradiate the sample in the sample cell to obtain an XRD pattern, thus successfully combining XRD and physical adsorption characterization methods in situ. Furthermore, by defining the projection coverage relationship between the first window and the sample cell, venting holes can be fabricated in the non-projection coverage area of ​​the sample, and the projection coverage area of ​​the sample can be kept flat, thereby simultaneously meeting the dual characterization requirements of XRD and physical adsorption.

Description

Technical Field

[0001] This invention relates to the field of materials characterization technology, specifically to an in-situ characterization device and method for XRD-physical adsorption. Background Technology

[0002] Physical adsorption analyzers and X-ray diffractometers (XRD) are two common characterization devices in the field of materials science. Physical adsorption analyzers are used to measure the adsorption capacity of a sample for gases, and can obtain information such as adsorption amount, specific surface area, and pore size distribution; XRD is used to analyze the crystal structure of materials, and can obtain information such as phase composition, lattice parameters, and grain size.

[0003] Studies have found that many materials undergo crystal structure evolution during gas adsorption. However, existing characterization methods are typically fragmented, involving first processing the sample and measuring the adsorption capacity in a physical adsorption instrument, and then transferring the sample to an X-ray diffractometer for structural characterization. This non-in-situ approach cannot capture the structural state of the sample under different adsorption capacities in real time, making it difficult to establish a correlation between adsorption capacity and changes in crystal structure.

[0004] Accordingly, a new technical solution is needed in this field to solve the above problems. Summary of the Invention

[0005] This invention aims to solve the aforementioned technical problem, namely, the inability of existing characterization devices to characterize the structural state of a sample under different adsorption amounts in real time and in situ. Based on this, this application provides an in-situ characterization device for XRD-physical adsorption. The in-situ characterization device includes: an X-ray diffractometer, which includes an X-ray source, an X-ray detector, and an in-situ cell. The in-situ cell includes a first housing assembly, a second housing assembly, and a sample cell assembly. The first housing assembly includes a first housing, a cover plate, and a first window. The cover plate is disposed on one side of the first housing along a first direction and has a window thereon. The first window is installed at the window. The cover plate, the first window, and the first housing together form a sealed first chamber. The X-ray source and the X-ray detector are respectively located on both sides of the first window along a second direction. The second housing assembly is... The first chamber is provided with a second housing and a second window, the second window being disposed on the side of the second housing near the cover plate along the first direction, and together with the second housing forming a sealed second chamber; the sample cell assembly is disposed in the second chamber, and a sample slot is formed on the side of the sample cell near the second window along the first direction; the second housing is provided with a first connection port communicating with the second chamber; a physical adsorption instrument, the physical adsorption instrument including a gas device, the gas device communicating with the first connection port; and a temperature control device configured to adjust the temperature of the second chamber; wherein the first direction and the second direction are perpendicular to each other.

[0006] In the preferred embodiment of the above-mentioned in-situ characterization device, the second window is hemispherical; the cross-section of the cover plate on the first reference surface formed by the first direction and the second direction is semi-circular; the outline of the window is adapted to the cross-sectional outline of the cover plate on the first reference surface; the orthographic projection of the first window on the first reference surface covers part of the orthographic projection of the second window on the first reference surface, and the center lines of the two projections are collinear.

[0007] In the preferred embodiment of the above-mentioned in-situ characterization device, an ear plate is provided on the edge of the cover of the second window, and the ear plate surrounds the second window in the circumferential direction; and the second housing includes a pressing assembly, the pressing assembly includes a first connecting seat and a pressing plate, the first connecting seat is sleeved outside the sample cell assembly and is disposed on the side of the second housing close to the cover plate along the first direction; the pressing plate is disposed on the side of the first connecting seat away from the second housing along the first direction, and the ear plate is pressed between the pressing plate and the first connecting seat.

[0008] In the preferred embodiment of the above-mentioned in-situ characterization device, a first flow channel is provided inside the first connecting seat, and a first inlet and a first outlet communicating with the first flow channel are provided on its outer wall; and the temperature control device includes a constant temperature device, the inlet end and the outlet end of the constant temperature device being respectively connected to the first inlet and the first outlet.

[0009] In the preferred embodiment of the above-mentioned in-situ characterization device, the gas device includes: Gas supply device and first air extraction device; A pipe assembly, one end of which is connected to the first connection port, and the other end of which is connected to the gas supply device and the first air extraction device respectively.

[0010] In the preferred embodiment of the above-mentioned in-situ characterization device, the pipeline assembly includes an outer pipe and an inner pipe disposed inside the outer pipe. One end of the inner pipe extends to the outside of the outer pipe and communicates with the first connection port, and the other end extends to the outside of the outer pipe and communicates with the gas supply device and the first air extraction device respectively. There is a gap between the inner wall of the outer pipe and the outer wall of the inner pipe. The outer pipe is provided with a second inlet and a second outlet communicating with the gap. The second inlet communicates with the inlet end of the thermostat, the second outlet communicates with the first inlet on the first connecting seat, and the first outlet on the first connecting seat communicates with the outlet end of the thermostat.

[0011] In the preferred embodiment of the above-mentioned in-situ characterization device, the pipe section of the inner tube located inside the outer tube is a corrugated pipe.

[0012] In the preferred embodiment of the above-mentioned in-situ characterization device, the in-situ pool further includes: A first anti-scattering baffle is disposed in the first chamber and located on the side of the second window near the cover plate along the first direction; the first anti-scattering baffle has an opening on the side of the second window near the second window along the first direction that is adapted to the outer contour of the second window; the first anti-scattering baffle is parallel to a second reference surface formed by the first direction and a third direction; A second anti-scattering baffle is disposed in the second chamber and located on the side of the sample cell assembly near the second window along the first direction; the second anti-scattering baffle is arranged parallel to the first anti-scattering baffle and spaced apart along the second direction; the orthographic projection of the second anti-scattering baffle onto the second reference plane covers a portion of the orthographic projection of the first anti-scattering baffle onto the second reference plane and at least a portion of the orthographic projection of the clearance opening onto the second reference plane; and The X-ray source is located on the side of the first anti-scattering baffle that is away from the second anti-scattering baffle along the second direction; the X-ray detector is located on the side of the second anti-scattering baffle that is away from the first anti-scattering baffle along the second direction. Wherein, the third direction is perpendicular to both the first direction and the second direction.

[0013] In the preferred embodiment of the above-mentioned in-situ characterization device, a first positioning structure is provided on the second housing, and a second positioning structure is provided on the first anti-scattering baffle to cooperate with the first positioning structure. The sample cell assembly is provided with a third positioning structure; the second anti-scattering baffle is provided with a fourth positioning structure that cooperates with the third positioning structure.

[0014] In the preferred embodiment of the above-mentioned in-situ characterization device, the first positioning structure is a first positioning groove and the second positioning structure is a first positioning protrusion; or the first positioning structure is a first positioning protrusion and the second positioning structure is a first positioning groove. The third positioning structure is the second positioning groove, and the fourth positioning structure is the second positioning protrusion; or the third positioning structure is the second positioning protrusion, and the fourth positioning structure is the second positioning groove.

[0015] In the preferred embodiment of the above-mentioned in-situ characterization device, the sample cell assembly includes: The first pool body is disposed on the side of the second chamber away from the second window, and a first connecting structure is provided on the side of the first chamber close to the second window along the first direction. The second pool body has the sample groove provided on the side of the second pool body close to the second window along the first direction, and a second connecting structure that cooperates with the first connecting structure is provided on the side of the second pool body away from the second window along the first direction.

[0016] In the preferred embodiment of the above-mentioned in-situ characterization device, a positioning mark is provided on the second pool body. The positioning mark is arranged along the outline of the orthographic projection of the first window on the second pool body in the first direction, so as to define the marking area enclosed by the positioning mark and the surrounding area outside the marking area on the second pool body.

[0017] In the preferred embodiment of the above-mentioned in-situ characterization device, the first connecting structure is a connecting protrusion and the second connecting structure is a connecting groove; or the first connecting structure is a connecting groove and the second connecting structure is a connecting protrusion.

[0018] In a preferred embodiment of the above-mentioned in-situ characterization device, a first connecting hole is provided on the outer wall of the first pool body, and a second connecting hole communicating with the first connecting hole is provided on the first connecting structure. The second connecting hole penetrates the second connecting structure along the first direction and communicates with the sample cell; and / or A third connection hole is provided on the wall of the second pool.

[0019] In the preferred embodiment of the above-mentioned in-situ characterization device, a filter element is provided in the second connection hole and / or the third connection hole.

[0020] In a preferred embodiment of the above-mentioned in-situ characterization device, the temperature control device includes a heating device and a cooling device. The heating device includes a heating element and a temperature sensing element. The temperature sensing element's temperature sensor head passes through the second housing and is disposed on the sample cell assembly. The second housing includes a heat-conducting block and an inner shell, which are sequentially disposed on the side of the first chamber away from the cover plate along the first direction. The heat-conducting block has a second flow channel and a heating channel inside, and a third inlet and a third outlet communicating with the second flow channel are provided on the outer wall of the heat-conducting block. The third inlet is connected to the cooling device, and the third outlet is connected to the outside of the first housing assembly. The heating element is disposed in the heating channel. The inner shell has a first connection port communicating with the second chamber, and the first connection port is connected to the gas device.

[0021] In the preferred embodiment of the above-mentioned in-situ characterization device, the first housing is provided with a first interface, a second interface, a third interface and a fourth interface communicating with the first chamber; and the first connection port is connected to the gas device through the first interface; the third inlet is connected to the inlet end of the cooling device through the second interface, and the third outlet is connected to the third interface; the lines of the heating element and the temperature detection element both pass through the fourth interface and are connected to the heating control element in the temperature control device.

[0022] In the preferred embodiment of the above-mentioned in-situ characterization device, the in-situ characterization device further includes a second suction device; and the first housing is provided with a fifth interface communicating with the first chamber, the fifth interface communicating with the second suction device; and / or the X-ray diffractometer further includes a lifting device, the output end of the lifting device being provided with the in-situ pool, so as to drive the in-situ pool to move along the first direction.

[0023] This application also provides a characterization method using the above-mentioned in-situ characterization device, the characterization method comprising: The sample to be tested is placed into the sample slot, and multiple vent holes are processed in the first detection area of ​​the sample to be tested using a perforating tool; then the second detection area of ​​the sample to be tested is flattened; wherein the first detection area is the area of ​​the sample surface not covered by the orthographic projection of the first window in the first direction, and the second detection area is the area of ​​the sample surface covered by the orthographic projection of the first window in the first direction. The temperature of the second chamber is kept constant at the desorption temperature using the temperature control device. Then, the second chamber is evacuated using a gas device until the pressure inside the second chamber is constant and no longer changes, thus completing the desorption process of the sample to be tested. The temperature of the second chamber is kept constant at the adsorption temperature using the temperature control device. Then, the first molar amount of adsorption gas is introduced into the second chamber using the gas device. After the pressure in the second chamber stabilizes, the X-ray source and X-ray detector are turned on to obtain the XRD pattern and measure the adsorption amount of the sample. Next, the gas device is started to continue to introduce the second molar amount of adsorbed gas into the second chamber. After the pressure stabilizes again, the X-ray source and X-ray detector are turned on again to obtain the XRD pattern and measure the adsorption amount of the sample. The above process is repeated until the pressure no longer changes after the adsorbed gas is introduced.

[0024] Those skilled in the art will understand that the XRD-physical adsorption in-situ characterization device of this application, by employing a dual-chamber in-situ cell and placing the sample cell assembly in a second chamber with a controllable gas environment and temperature, can accurately characterize the adsorption capacity of the sample to be tested. Simultaneously, by utilizing the transmission light path formed by the first and second windows, X-rays can irradiate the sample to be tested within the sample cell and obtain XRD patterns, thus successfully combining XRD and physical adsorption characterization methods in situ. By defining the projection coverage relationship between the first window and the sample cell, the sample to be tested within the sample cell can simultaneously meet the characterization requirements of both XRD and physical adsorption. Specifically, venting holes are processed in the area of ​​the sample not covered by the projection of the first window to meet the gas exchange requirements of physical adsorption; the area of ​​the sample covered by the projection of the first window remains flat to meet the XRD testing requirements, thereby avoiding phenomena such as sample boiling, cracking, or bulging during gas extraction, ensuring the reliability of the XRD test results without affecting the accurate measurement of adsorption capacity. Furthermore, by integrating the aforementioned in-situ cell, X-ray diffractometer, physical adsorption instrument, and temperature control device, a complete coupled characterization system is formed, enabling the testing device to simultaneously characterize the sample under test using both XRD and physical adsorption.

[0025] Furthermore, by setting the second window to a hemispherical shape and adapting the contour of the first window to the contour of the semi-circular cover plate, the range of X-ray incident angles and diffraction exit angles can be increased, thereby enabling in-situ XRD testing over a wide angle range. In addition, by making the center lines of the orthographic projections of the two windows on the first reference plane collinear, refraction loss, scattering interference, and optical path difference of X-rays can be reduced, improving the intensity and signal-to-noise ratio of the XRD pattern.

[0026] Furthermore, by setting an ear plate on the outer edge of the second window and clamping and pressing the ear plate with the first connecting seat and the pressure plate, the sealing effect of the second chamber is improved.

[0027] Furthermore, by setting a first flow channel in the first connecting seat, when the second chamber is in a high temperature test environment or a low temperature test environment, it can effectively prevent the seal from aging, deforming or failing due to severe thermal shock or cold shock, thereby ensuring that the second chamber can still maintain excellent sealing performance in a wide temperature range.

[0028] Furthermore, by setting the piping assembly in the gas device as a double-layer piping structure and connecting the gap between the double-layer piping with the first flow channel and the constant temperature device to form a circulating flow channel, on the one hand, the gas can be kept at a constant temperature during transmission when supplying gas to the second chamber, thereby effectively reducing the interference to the adsorption amount test and improving the accuracy of the physical adsorption characterization of the sample to be tested; on the other hand, it can also effectively avoid the aging, deformation or failure of the sealing parts due to severe thermal shock or cold shock.

[0029] Furthermore, by setting a first anti-scattering baffle in the first chamber and a second anti-scattering baffle in the second chamber, and ensuring that the orthographic projection of the second anti-scattering baffle on the second reference plane covers part of the orthographic projection of the first anti-scattering baffle on the second reference plane and at least part of the orthographic projection of the clearance opening on the second reference plane, while arranging the X-ray source on the side of the first anti-scattering baffle away from the second anti-scattering baffle along the second direction, and arranging the X-ray detector on the side of the second anti-scattering baffle away from the first anti-scattering baffle along the second direction, it is possible to ensure that the X-rays emitted from the X-ray source can pass smoothly through the clearance opening to irradiate the sample to be tested in the sample cell, and that the diffraction signal generated by the sample to be tested is emitted through the gap between the second anti-scattering baffle and the sample to be tested and received by the X-ray detector, and to effectively filter out the scattering signals generated by the air and the window, thereby reducing the background noise of the XRD pattern.

[0030] Furthermore, by setting matching positioning structures for the first and second anti-scattering baffles respectively, it is not only convenient to install the two anti-scattering baffles, but also to ensure that the two are parallel to each other.

[0031] Furthermore, by setting the sample cell to a split structure, it is convenient to remove the second cell for sample loading, puncturing the first detection area, and pressing and leveling operations in the second detection area.

[0032] Furthermore, by setting positioning marks on the second cell, it is convenient to punch holes in the first detection area of ​​the sample to be tested and to flatten the second detection area, so that the sample to be tested can simultaneously meet the characterization requirements of XRD and physical adsorption.

[0033] Furthermore, by opening a connection hole on the sample cell to connect to the sample slot, it is beneficial to discharge the gas generated by the desorption of the sample to be tested, and to avoid phenomena such as boiling, cracking or bulging of the sample to be tested.

[0034] Furthermore, by installing a filter element inside the connection hole, it is possible to ensure the conduction of desorption gas while effectively intercepting fine sample powder, preventing the powder from leaking out with the airflow.

[0035] Furthermore, by using an inner shell, a heat-conducting block, and a second window to form a second chamber, and simultaneously setting a heating channel and a second flow channel within the heat-conducting block, it is helpful to regulate the temperature of the chamber where the sample to be tested is located, thereby meeting the characterization requirements of the sample to be tested.

[0036] Furthermore, by integrating multiple interfaces on the housing assembly, the various pipelines and wiring inside the first chamber can be organized to avoid the problem of pipelines intertwining, and the in-situ pool can be quickly connected and assembled with the gas device and temperature control device.

[0037] Furthermore, by providing a fifth interface on the housing assembly that communicates with the first chamber and connecting this fifth interface to the second pumping device, the first chamber can be kept in a vacuum state. This not only eliminates the scattering and absorption of X-rays by air and further improves the intensity of the XRD signal, but also provides thermal insulation, reducing heat loss from the second chamber and thus improving the accuracy of adsorption characterization.

[0038] Furthermore, by adding a lifting device to the instrument body, it is helpful to adjust the sample to be tested in the sample cell to the focal point of the X-ray optical path, thereby improving the accuracy of XRD detection.

[0039] Those skilled in the art will understand that the characterization method of this application utilizes the projection of a first window onto the surface of the sample to distinguish between a first detection area and a second detection area. By creating an exhaust vent in the first detection area and flattening the second detection area, the sample in the sample chamber can simultaneously meet the characterization requirements of XRD and physical adsorption. During the test, a sequential quantitative gas injection method is adopted. After each pressure stabilization, XRD patterns and adsorption data are simultaneously collected until the sample reaches adsorption saturation, thereby obtaining structural evolution information corresponding to different adsorption amounts. Attached Figure Description

[0040] The preferred embodiments of the present invention are described below with reference to the accompanying drawings, in which: Figure 1 This is a structural diagram of the in-situ characterization device for XRD-physical adsorption in this application; Figure 2 This is a structural diagram of the in-situ pool of this application. Figure 3 This is a cross-section of the in-situ pool of this application. Figure 1 ; Figure 4 This is a cross-section of the in-situ pool of this application. Figure 2 ; Figure 5 This is a cross-sectional view of the in-situ pool without the first housing assembly in this application; Figure 6 This is a structural diagram of the sample cell assembly of this application; Figure 7 This is a structural diagram of the first pool body of this application; Figure 8 This is a cross-sectional view of the first pool body of this application; Figure 9 This is a structural diagram of the second pool body in this application; Figure 10 This is a cross-sectional view of the second pool body in this application; Figure 11 This is a structural diagram of the piping assembly of this application; Figure 12 This is a cross-sectional view of the piping assembly of this application; Figure 13 This is a cross-sectional view of the heat-conducting block of this application.

[0041] Explanation of reference numerals in the attached drawings: 100, X-ray diffractometer; 1, in-situ cell; 11, first housing assembly; 111, first housing; 1111, first sub-housing; 11111, first interface; 11112, second interface; 111121, second connector; 11113, third interface; 11114, fourth interface; 11115, fifth interface; 1112, second sub-housing; 11121, first connecting piece; 1113, clamp; 112, cover plate; 113, first window; 114, first chamber; 12, second housing. Body assembly; 121, second shell; 1211, base; 1212, heat-conducting block; 12121, second flow channel; 12122, heating channel; 12123, third inlet; 12124, third outlet; 1213, inner shell; 12131, first connecting block; 12132, cylinder; 12133, second connecting block; 122, second window; 1221, ear plate; 123, pressing assembly; 1231, first connecting seat; 12311, first flow channel; 12312, annular protrusion; 1232, pressing plate; 12 4. Second chamber; 13. Sample cell assembly; 131. First cell body; 1311. First connector; 13111. Second positioning groove; 1312. Connecting groove; 1313. First connecting hole; 1314. Second connecting hole; 1315. Air duct; 1316. Second connecting piece; 1317. Insertion groove; 132. Second cell body; 1321. Sample cell; 1322. Connecting protrusion; 13221. External thread; 1323. Third connecting hole; 14. First anti-scattering baffle; 141. Clearance opening; 15. Second anti-scattering baffle 1. Radiation shield; 151. Second connector; 16. Support column; 2. Pipe assembly; 21. Outer pipe; 22. Inner pipe; 221. First pipe section; 222. Second pipe section; 223. Third pipe section; 23. First tee connector; 231. First connecting end; 232. Second connecting end; 233. Third connecting end; 3. Lifting device; 4. Thermocouple; 5. Second tee connector; 51. Fourth connector; 6. X-ray source; 7. X-ray detector; 8. Instrument body; 9. First pipeline; 200. Control device; 300. Liquid nitrogen tank. Detailed Implementation

[0042] Preferred embodiments of this application will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of this application and are not intended to limit the scope of protection of this application.

[0043] It should be noted that in the description of this application, the terms "upper", "lower", "inner", "top", "bottom", etc., indicating the direction or positional relationship are based on the direction or positional relationship shown in the drawings. This is only for the convenience of description and is not intended to indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this application.

[0044] Furthermore, it should be noted that, in the description of this application, unless otherwise explicitly specified and limited, the terms "set" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, a direct connection, or an indirect connection through an intermediate medium; or they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0045] To address the limitation of existing characterization devices in their in-situ real-time and synchronous characterization of the structural state of samples under different adsorption capacities, this application provides an in-situ XRD-physical adsorption characterization device. This device combines two characterization methods in situ, enabling real-time and synchronous measurement of the adsorption capacity of the material and its corresponding structural state under adsorption conditions. (See below for reference.) Figure 1-13 The in-situ characterization apparatus for XRD-physical adsorption of this application is described below.

[0046] like Figure 1-4 As shown, the in-situ characterization device includes an X-ray diffractometer 100, a physical adsorption apparatus, a temperature control device, and a second pumping device. The temperature control device includes a heating element, a control device 200, and a cooling device. The heating element includes a heating element and a temperature detection element. The cooling device consists of a liquid nitrogen tank 300 and a pump speed control element. The inlet of the pump speed control element is connected to the liquid nitrogen tank 300 to adjust the pumping speed of the liquid nitrogen. The control device 200 internally includes a temperature control element, a lifting control element, and a constant temperature device. The temperature control element is connected to the heating element and the temperature detection element to adjust the heating temperature of the heating element. The lifting control element outputs a control signal to control the operating status of the lifting device. The X-ray diffractometer 100 includes an instrument body 8, an X-ray source 6, an X-ray detector 7, an in-situ cell 1, and a lifting device 3. The instrument body contains the in-situ cell 1, the X-ray source 6, the X-ray detector 7, and the lifting device 3 connected to the lifting control element. The X-ray source 6 and the X-ray detector 7 are located on opposite sides of the in-situ cell 1 along a second direction. The in-situ cell 1 is set at the output end of the lifting device 3 so that the in-situ cell 1 can move in the first direction under the action of the lifting device 3, thereby facilitating the adjustment of the position of the sample to be tested inside the in-situ cell 1 in the first direction, so that the sample to be tested is aligned with the focal point of the X-ray light path formed by the X-ray source 6 and the X-ray detector 7.

[0047] The first direction refers to Figure 2-6 The Z-direction shown includes both the positive and negative directions indicated by the arrow; the second direction refers to... Figure 2-6 The Y-direction shown includes both the positive and negative directions indicated by the arrow.

[0048] For example, in other embodiments, the lifting device 3 is not necessary, and those skilled in the art can adjust it according to the setting requirements. Without the lifting device 3, the X-ray source 6 and X-ray detector 7 can be configured as lifting structures, which can also achieve alignment between the sample to be tested and the focal point of the X-ray optical path.

[0049] See next Figure 1 , 2 11 and 12, the physical adsorption apparatus includes a gas device, which includes a gas supply device (not shown in the figure), a first gas extraction device (not shown in the figure), and a pipe assembly 2. The pipe assembly 2 includes an outer pipe 21, an inner pipe 22, and two first tee joints 23. The inner pipe 22 is divided into a first pipe section 221, a second pipe section 222, and a third pipe section 223 along its axial direction. The first pipe section 221 is coaxially sleeved inside the outer pipe 21. The second pipe section 222 and the third pipe section 223 extend from the two axial ends of the first pipe section 221 and protrude to the outside of the outer pipe 21, respectively. The second pipe section 222 can communicate with the in-situ pool 1, and the third pipe section 223 can communicate with the first gas extraction device and the gas supply device, thereby providing gas to the in-situ pool 1 or evacuating the in-situ pool 1. There is a gap between the outer wall of the first pipe section 221 and the inner wall of the outer pipe 21. The two ends of the outer pipe 21 along its axial direction are respectively connected to the outer walls of the first connecting ends 231 of the two first tee joints 23. The second pipe segment 222 and the third pipe segment 223 each have one end connected to the first pipe segment 221, which is then connected to the inner wall of the second connecting end 232 of the corresponding first tee connector 23. The other end of each pipe segment extends out of the corresponding first tee connector 23. The third connecting ends 233 of the two first tee connectors 23 serve as the second inlet and the second outlet of the gap, respectively. The second inlet is connected to the inlet of the thermostat.

[0050] In order to improve the heat exchange effect between the first heat exchange medium and the gas in the constant temperature device, the first pipe section 221 is a corrugated pipe. This corrugated pipe can increase the heat exchange area between the gas and the first heat exchange medium, effectively improving the heat exchange efficiency, thereby ensuring that the temperature of the gas sent into the in-situ pool 1 is the same as the characterization temperature of the sample to be tested. In addition, the inlet and outlet ends of the constant temperature device are relative to the pipe assembly.

[0051] For example, in other embodiments, the first tee connector 23 is not mandatory, and those skilled in the art can choose to include it as needed. If the first tee connector 23 is not included, a support ring can be provided on the outer wall of the first pipe segment 221 to coaxially support the inner pipe 22 inside the outer pipe 21, maintaining an annular gap between the first pipe segment 221 and the outer pipe 21. In this case, a second inlet and a second outlet communicating with the gap can be directly formed on the wall of the outer pipe 21.

[0052] See next Figure 2-5 The in-situ cell 1 includes a first housing assembly 11, a second housing assembly 12, a sample cell assembly 13, a support column 16, a first anti-scattering baffle 14, and a second anti-scattering baffle 15. The first housing assembly 11 includes a first housing 111, a cover plate 112, and a first window 113. The first housing 111 is located at the output end of the lifting device 3. The cover plate 112 is located on one side of the first housing 111 along a first direction, and a window is provided thereon. The first window 113 is installed at the window, so that the cover plate 112, the first window 113, and the first housing assembly 11 together form a sealed first chamber 114. The first window 113, when projected onto the third reference plane formed by the second and third directions, can cover the portion of the sample cell assembly 13's sample groove 1321 projected onto the third reference plane. This allows X-rays emitted from the X-ray source 6 to pass through the first window 113 and irradiate the sample to be tested in the sample groove 1321. Furthermore, the diffraction rays generated by the sample to be tested can also pass through the first window 113 and be received by the X-ray detector 7.

[0053] Among them, third-party refers to Figure 2-6 The X direction shown includes both the positive and negative directions indicated by the arrow.

[0054] For example, in order to improve the sealing effect of the cover plate 112 and the first housing 111, a sealing ring can be provided at the connection between the cover plate 112 and the first housing 111.

[0055] See next Figure 2-4The first housing 111 includes a first sub-housing 1111, a second sub-housing 1112, and a clamp 1113. The first sub-housing 1111 is located at the output end of the lifting device 3. The second sub-housing 1112 is located on the side of the first sub-housing 1111 away from the lifting device 3 along the first direction. The clamp 1113 is fitted around the outer periphery of the mating portion of the first sub-housing 1111 and the second sub-housing 1112 to achieve a tight connection between the two. The second sub-housing 1112 has a first connecting piece 11121 arranged around its outer wall on the side of the second sub-housing 1111 away from the first sub-housing 1111 along the first direction. The outer contour of the first connecting piece 11121 projected onto the third reference plane formed by the second and third directions is square. The cover plate 112 is semi-cylindrical, and its orthographic projection on the third reference plane is square, matching the orthographic projection of the first connecting piece 11121 on the third reference plane. This allows the cover plate 112 to be installed on the second sub-shell 1112, forming a first chamber 114 together with the first sub-shell 1111 and the second sub-shell 1112. The cover plate 112 has a semi-circular cross-section on the first reference plane formed by the first and second directions. The outline of the window on the first reference plane matches the cross-sectional outline of the cover plate 112 on the first reference plane, i.e., the cross-section of the window on the first reference plane has a semi-circular outline. At this time, the first window 113 installed at the window has a semi-circular cross-section on the first reference plane. The X-ray source 6 and the X-ray detector 7 are located on both sides of the first window 113 along the second direction, thereby increasing the incident angle range and diffraction exit angle range of X-rays, thus realizing in-situ XRD testing with a wide angle range. The orthographic projection of the first window 113 onto the first reference plane covers part of the orthographic projection of the second window 122 onto the first reference plane, and the center lines of the two projections are collinear, which helps to reduce X-ray refraction loss, scattering interference and optical path difference, and improve the intensity and signal-to-noise ratio of the XRD pattern.

[0056] To ensure that the orthographic projection of the first window slab 113 on the first reference plane is semi-circular, a fifth positioning structure can be provided on the side of the first sub-housing 1111 away from the lifting device 3 along the first direction; a sixth positioning structure that cooperates with the fifth positioning structure can be provided on the side of the second sub-housing 1112 near the first sub-housing 1111 along the first direction; a seventh positioning structure can be provided on the side of the cover plate 112 near the first connecting piece 11121 along the first direction; and an eighth positioning structure that cooperates with the seventh positioning structure can be provided on the side of the first connecting piece 11121 near the cover plate 112 along the first direction. One of the fifth and sixth positioning structures can be a third positioning groove, and the other a third positioning protrusion. One of the seventh and eighth positioning structures can be a fourth positioning groove, and the other a fourth positioning protrusion.

[0057] For example, the shape of the cover plate 112 is not fixed in this application, as long as the orthographic projection of the cover plate 112 on the first reference surface is semi-circular. For example, the cover plate 112 can also be hemispherical, and correspondingly the outer contour of the projection of the first connecting piece 11121 on the first reference surface can be set as circular.

[0058] For example, the fastening connection method of the first sub-shell 1111 and the second sub-shell 1112 is not fixed in this application, as long as a fastening connection between the first sub-shell 1111 and the second sub-shell 1112 can be achieved. For example, the first sub-shell 1111 and the second sub-shell 1112 can also be connected by threaded fasteners or welding.

[0059] As another example, in order to improve the sealing performance of the connection between the first sub-shell 1111 and the second sub-shell 1112, an annular sealing gasket can be provided at the connection between the first sub-shell 1111 and the second sub-shell 1112. In addition, thermal insulation components, such as thermal insulation cotton, can be provided on the outer walls of the first sub-shell 1111 and the second sub-shell 1112.

[0060] For example, this application does not limit the material of the first window 113, as long as it can transmit X-rays. For example, it can be beryllium.

[0061] See next Figure 2-4 The first sub-shell 1111 has a first interface 11111, a second interface 11112, a third interface 11113, a fourth interface 11114, and a fifth interface 11115 that communicate with the first chamber 114. The first interface 11111, the second interface 11112, and the third interface 11113 are respectively equipped with a first connector, a second connector 111121, and a third connector. The first connector communicates with the second pipe section 222, and the second connector 111121 communicates with the outlet end of the pump speed control component. The fourth interface 11114 is equipped with an aviation electrical plug, which connects to the heating control component and the lifting control component via corresponding wiring. A second tee connector 5 is provided at the fifth interface 11115. The first end of the second tee connector 5 is connected to the fifth interface 11115, and the second end is provided with a fourth connector 51. The fourth connector 51 is provided with two connectors. One connector is connected to the second outlet, and the other connector is connected to the outlet end of the constant temperature device. The third end is provided with a fifth connector for connecting to the second air extraction device.

[0062] For example, the positions of the first interface 11111, the second interface 11112, the third interface 11113, the fourth interface 11114, and the fifth interface 11115 are not fixed in this application, and those skilled in the art can adjust them according to the setting requirements. For example, the first interface 11111, the second interface 11112, the third interface 11113, the fourth interface 11114, and the fifth interface 11115 can also be provided on the second housing 121.

[0063] As another example, in other embodiments, the second three-way connector 5 is not mandatory, and those skilled in the art can select it according to the setting requirements. In the absence of a second three-way interface, a sixth interface and a seventh interface can be provided on the first housing 111, and a sixth connector communicating with the second outlet and a seventh connector communicating with the outlet end of the thermostat can be provided at the sixth interface and the seventh interface, respectively, while the fifth interface 11115 is provided with a fifth connector communicating with the second air extraction device.

[0064] See next Figure 3-5 The second housing assembly 12 and the first anti-scattering baffle 14 are both disposed in the first chamber 114. The second housing assembly 12 includes a second housing 121, a second window 122, and a pressing assembly 123. A support column 16 is disposed at the bottom of the first sub-housing 1111, which is disposed opposite to the cover plate 112 in a first direction. The second housing 121 is disposed on the side of the support column 16 near the cover plate 112 along the first direction. The pressing assembly 123 includes a first connecting seat 1231 and a pressing plate 1232. The first connecting seat 1231 is disposed on the side of the second housing 121 near the cover plate 112 along the first direction; the pressing plate 1232 is disposed on the side of the first connecting seat 1231 opposite to the second housing 121. The second window 122 is hemispherical and is located on the side of the first connecting seat 1231 opposite to the second housing 121 along the first direction. The opening of the second window 122 faces the first connecting seat 1231 along the first direction. An ear plate 1221 is provided along the edge of the opening of the second window 122, surrounding and pressing the pressure plate 1232 between the pressure plate 1232 and the first connecting seat 1231. This allows the second window 122, the pressure plate assembly 123, and the second housing 121 to collectively form a sealed second chamber 124. A first anti-scattering baffle 14 is located on the side of the second window 122 along the first direction near the cover plate 112, and is parallel to the second reference plane formed by the first direction and the third direction. The first anti-scattering baffle 14 has a clearance opening 141 along the side of the first direction near the second window 122 that matches the outer contour of the second window 122, allowing X-rays emitted from the X-ray source 6 to pass smoothly through the clearance opening 141 and irradiate the sample to be tested. The first anti-scattering baffle 14 is located on both sides of the relief opening 141 along the third direction and is respectively disposed on the pressure plate 1232.

[0065] To improve the sealing performance between the ear plate 1221 and the first connecting seat 1231, a first sealing structure can be provided on the side of the ear plate 1221 close to the first connecting seat 1231 along the first direction, and a second sealing structure that cooperates with the first sealing structure can be provided on the first connecting seat 1231. One of the first sealing structure and the second sealing structure can be an annular protrusion 12312, and the other can be an annular groove.

[0066] Furthermore, to ensure that the first anti-scattering baffle 14 is parallel to the second reference plane, a ninth positioning structure can be provided on the side of the first connecting seat 1231 near the baffle along the first direction, and a tenth positioning structure can be provided on the side of the pressure plate 1232 near the first connecting seat 1231 along the first direction. First positioning structures are provided on both sides of the second window along the third direction on the pressure plate 1232, and second positioning structures that cooperate with the first positioning structures are provided on both sides of the clearance opening 141 along the third direction on the first anti-scattering baffle 14. One of the ninth and tenth positioning structures is a fifth positioning groove, and the other is a fifth positioning protrusion; one of the first and second positioning structures is a first positioning protrusion, and the other is a first positioning groove. It should also be noted that the ninth and tenth positioning structures are not mandatory, and those skilled in the art can select them according to their needs. In the absence of the ninth and tenth positioning structures, positioning marks can be provided on the first connecting seat 1231 or the second housing 121 to ensure the installation position of the pressure plate 1232, thereby ensuring that the first anti-scattering baffle 14 is parallel to the second reference plane.

[0067] See next Figure 3-5 The first connecting seat 1231 is provided with a first flow channel 12311, and its outer wall is provided with a first inlet and a first outlet that communicate with the first flow channel 12311. The first inlet is connected to the second inlet through a fourth connector 51, and the first outlet is connected to the outlet end of the thermostat through another fourth connector 51, thereby forming a circulating flow channel with the thermostat and the gap between the inner and outer pipes in the pipe assembly.

[0068] During operation, the first heat exchange medium in the circulating channel flows into the gap between the inner and outer tubes from the second inlet, ensuring that the temperature of the gas supplied to the second chamber is consistent with the temperature of the second chamber. This effectively reduces interference with the adsorption capacity test and improves the accuracy of the physical adsorption characterization of the sample. Subsequently, the first heat exchange medium enters the first channel through the second outlet and the first inlet. This effectively buffers temperature shocks when the second chamber 124 is in a high-temperature or low-temperature testing environment, preventing the seals from aging, deforming, or failing due to severe thermal or cold shocks. This ensures that the second chamber 124 maintains excellent sealing performance over a wide temperature range. Finally, it flows back to the thermostat from the first outlet.

[0069] See next Figure 3-5 The second housing 121 includes a base 1211, a heat-conducting block 1212, and an inner housing 1213. The base 1211 is located on the side of the support column 16 near the cover plate 112 along the first direction, and the heat-conducting block 1212 is located on the side of the base 1211 away from the support column 16 along the first direction. The heat-conducting block 1212 has a second flow channel 12121 and a heating channel 12122 inside. The outer wall of the heat-conducting block 1212 has a third inlet 12123 and a third outlet 12124 communicating with the second flow channel 12121. The third inlet 12123 is connected to the second connector 111121 via a second pipe, and the third outlet 12124 is connected to the third connector via a third pipe, thereby enabling cooling of the second chamber 124. A heating element is installed inside the heating channel 12122. The heating element is connected to an aviation electrical plug via a circuit, thereby connecting to a heating control unit to heat the second chamber 124. By using the above settings, the temperature environment of the second chamber 124 can be adjusted to meet the characterization requirements of the sample to be tested.

[0070] For example, the installation of support column 16 and / or base 1211 is not mandatory, and those skilled in the art can choose according to the installation requirements. In the absence of support column 16 and base 1211, heat-conducting block 1212 is disposed on the side of first sub-housing 1111 away from cover plate 112 along a first direction.

[0071] As another example, this application does not limit the second heat exchange medium provided by the cooling device, as long as it can cooperate with the heating device to adjust the temperature of the second chamber 124. For example, the second heat exchange medium can be liquid nitrogen.

[0072] See next Figure 3-8The sample cell assembly 13 is disposed in the second chamber 124 and includes a first cell body 131 and a second cell body 132. The first cell body 131 is disposed on the heat-conducting block 1212, and the second cell body 132 is disposed on the side of the first cell body 131 away from the heat-conducting block 1212 along a first direction. A second connecting piece 1316 is disposed on the outer wall of the first cell body 131, which is arranged around its outer wall. The second connecting piece 1316 is flush with the side of the first cell body 131 near the heat-conducting block 1212 along the first direction and is disposed on the heat-conducting block 1212. An insertion groove 1317 is also provided on the outer wall of the first cell body 131. The inner shell 1213 includes a first connecting block 12131, a cylindrical body 12132, and a second connecting block 12133. The first connecting block 12131 is sleeved on the outside of the sample cell, and the second connecting piece 1316 is pressed between the heat-conducting block 1212 and the first connecting block 12131. A cylindrical body 12132 is fitted outside the sample cell and is located on the side of the first connecting block 12131 away from the heat-conducting block 1212. A second connecting block 12133 is fitted outside the sample cell and is located on the side of the cylindrical body 12132 away from the first connecting block 12131 along a first direction. A first connecting seat 1231 is provided on the side of the second connecting block 12133 away from the cylindrical body 12132 along the first direction. A first connecting port communicating with the second chamber 124 is provided on the first connecting block 12131. The first connecting port is connected to the first interface 11111 through a first pipe 9, so that the second chamber 124 meets the characterization requirements of the sample under the action of the first air extraction device and the air supply device. A second connecting port is provided on the second connecting block 12133, which communicates with the insertion slot 1317. The temperature detection element is a thermocouple 4. The temperature measuring head of the thermocouple 4 passes through the second connecting port and is inserted into the insertion slot 1317 to detect the ambient temperature of the second chamber 124. Thermocouple 4 is connected to the aviation electrical plug via a line, thereby connecting to the heating control component, which works with the heating component to heat up the second chamber 124.

[0073] To improve the sealing effect of the second chamber 124, a sealing gasket can be provided between the second connecting block 12133 and the first connecting seat 1231; a third sealing structure and a fourth sealing structure are respectively provided on both sides of the second connecting piece 1316 along the first direction; a fifth sealing structure that seals with the third sealing structure is provided on the heat-conducting block 1212; and a sixth sealing structure that seals with the fourth sealing structure is provided on the first connecting block 12131; and connecting grooves 1312 for inserting and connecting the cylinder 12132 are provided on opposite sides of the first connecting block 12131 and the second connecting block 12133. One of the third and fifth sealing structures is a second annular groove, and the other is a second annular protrusion 12312; one of the fourth and sixth sealing structures is a third annular groove, and the other is a third annular protrusion 12312. Furthermore, a sealing sleeve is fitted around the thermocouple located at the second connection port to improve the sealing performance of the second chamber.

[0074] See next Figure 3-8 Two first connectors 1311 are provided on the outer wall of the first pool body 131, and the two first connectors 1311 are respectively located on both sides of the first pool body 131 along a third direction. Each first connector 1311 is provided with a third positioning structure on the side of the second pool body 132 along the first direction, which is a second positioning groove 13111. The second anti-scattering baffle 15 is provided in the second chamber 124 and is located on the side of the second pool body 132 along the first direction near the second window 122. Two second connectors 151 are provided on the side of the second anti-scattering baffle along the first direction near the second pool body 132, and the two second connectors 151 are respectively located on both sides of the second anti-scattering baffle along a third direction. Each second connector 151 is provided with a fourth positioning structure that cooperates with the third positioning structure. The fourth positioning structure is a second positioning protrusion provided on the side of the second connector 151 away from the second anti-scattering baffle along the first direction, thereby positioning and installing the second anti-scattering baffle 15 on the first pool body 131, and making the second anti-scattering baffle 15 and the first anti-scattering baffle 14 parallel to each other and spaced apart along the second direction.

[0075] For example, the specific configuration of the third and fourth positioning structures in this application is not fixed, and those skilled in the art can adjust them according to the configuration requirements. For instance, the third positioning structure can also be a second positioning protrusion, and the fourth positioning structure can be a second positioning groove.

[0076] See next Figure 3-6 The second anti-scattering baffle 15, with its orthogonal projection onto the second reference plane, covers the portion of the first anti-scattering baffle 14 projected onto the second reference plane and the portion of the obstruction opening 141 projected onto the second reference plane. The X-ray source 6 is located on the side of the first anti-scattering baffle 14 facing away from the second anti-scattering baffle 15 along the second direction; the X-ray detector 7 is located on the side of the second anti-scattering baffle 15 facing away from the first anti-scattering baffle 14 along the second direction. This arrangement ensures that the X-rays emitted from the X-ray source 6 pass smoothly through the obstruction opening 141 and irradiate the sample to be tested within the sample chamber 1321. Furthermore, the diffraction signal generated by the sample to be tested exits through the gap between the second anti-scattering baffle 15 and the sample to be tested and is received by the X-ray detector 7. It also effectively filters out scattering signals generated by air and the window, thereby reducing the background noise of the XRD pattern.

[0077] For example, the orthographic projection of the second anti-scattering baffle 15 onto the second reference plane can also completely cover the orthographic projection of the clearance opening 141 onto the second reference plane.

[0078] See next Figure 6-10The first pool body 131 has a first connecting structure, which is a connecting groove 1312, provided on the side of the first pool body 131 near the second window 122 along the first direction. The connecting groove 1312 has an internal thread on its wall. The second pool body 132 has a sample groove 1321 provided on the side of the second pool body 132 near the second window 122 along the first direction, and a second connecting structure, which is a connecting protrusion 1322, provided on the side of the second pool body 132 away from the second window 122 along the first direction. The connecting protrusion 1322 has an external thread 13221 on its outer wall. The connecting protrusion 1322 mates with the connecting groove 1312, allowing the second pool body 132 to be threadedly installed onto the first pool body 131. In addition, the first pool body 131 has a vent 1315 that communicates with the connecting groove 1312 on the side of the first pool body 131 close to the second pool body 132 along the first direction. This is used to help the tiny cavity in the thread gap and the second chamber 124 to communicate better, avoid interference with the adsorption process of the sample to be tested, and thus improve the accuracy of physical adsorption characterization.

[0079] To facilitate pretreatment of the sample in sample cell 1321, a positioning mark can be provided on the second cell 132. The positioning mark is set along the outline of the orthographic projection of the first window 113 onto the second cell 132 in the first direction, thereby defining the marked area and the surrounding area outside the marked area on the second cell 132. The marked area corresponds to the second detection area of ​​the sample, and the surrounding area corresponds to the first detection area of ​​the sample. The first detection area is the area of ​​the sample surface not covered by the orthographic projection of the first window 113 in the first direction, and the second detection area is the area of ​​the sample surface covered by the orthographic projection of the first window 113 in the first direction.

[0080] For example, the specific configuration of the first and second connecting structures in this application can be adjusted. For instance, the first connecting structure can be a connecting protrusion, and the second connecting structure can be a connecting groove that mates with the connecting protrusion. In this case, the outer wall of the connecting protrusion has an external thread, and the inner wall of the connecting groove has an internal thread, allowing the second pool body to be threaded onto the first pool body. Correspondingly, the second pool body has an air guide hole communicating with the connecting groove on the side closest to the first pool body along the first direction.

[0081] See next Figure 1 and 2The outer wall of the first pool body 131 is provided with a first connecting hole 1313 and a second connecting hole 1314. The bottom of the connecting groove 1312 is provided with a second connecting hole 1314 communicating with the first connecting hole 1313. The second connecting hole 1314 is connected to a protrusion through the first direction and communicates with the sample groove 1321, thereby facilitating the discharge of gas desorbed from the sample. The outer wall of the second pool body 132 is provided with a third connecting hole 1323 communicating with the sample groove 1321. Filter elements are installed in the third connecting hole 1323 and the second connecting hole 1314, which can effectively intercept fine sample powder while ensuring the conduction of desorbed gas, preventing powder from leaking out with the airflow.

[0082] For example, when the first connecting structure is a connecting protrusion and the second connecting structure is a connecting groove, a second connecting hole can be opened on the connecting protrusion and the second connecting hole can penetrate through the second pool body corresponding to the connecting groove, so that the second connecting hole communicates with the sample pool.

[0083] For example, this application does not limit the type of filter element, such as a sintered filter element. Furthermore, the first connecting hole 1313 can be a through hole or a blind hole, as long as it can communicate with the second connecting hole 1314.

[0084] For example, the provision of the first connecting hole 1313 and the second connecting hole 1314 is not mandatory; those skilled in the art can choose according to the configuration requirements. If the first connecting hole 1313 and the second connecting hole 1314 are not provided, a third connecting hole 1323 needs to be opened on the outer wall of the second pool body 132. Furthermore, the provision of the third connecting hole 1323 is not mandatory; those skilled in the art can choose according to the configuration requirements. If the third connecting hole 1323 is not provided, the first connecting hole 1313 and the second connecting hole 1314 need to be opened on the first pool body 131, and the second connecting hole 1314 needs to communicate with the sample tank 1321.

[0085] The characterization method using the above-mentioned in-situ characterization device is described below.

[0086] Characterization methods include:

[0087] S101. Sample loading and pretreatment First, remove the cover plate 112, then remove the pressing assembly 123 and the second window 122 as a whole, then take out the second anti-scattering baffle 15 and unscrew the second pool body 132; The sample to be tested is placed in the sample slot 1321 of the second pool 132; Multiple vent holes are machined in the first detection area of ​​the sample to be tested using a perforating tool, and the second detection area of ​​the sample to be tested is flattened using a flattening tool.

[0088] S102, Pool assembly Install the second cell 132, which is loaded with the sample to be tested, onto the first cell 131 using threads; remove the original sealing gasket between the second connecting block 12133 and the tablet assembly 123, and replace it with a new sealing gasket; Next, the second anti-scattering baffle 15 is installed on the first pool body 131, and then the pressing assembly 123 and the second window 122 are installed as a whole on the second connecting block 12133, and finally the cover plate 112 is installed.

[0089] S103, Desorption Treatment The second evacuation device is turned on to evacuate the first chamber 114, so that the first chamber 114 is in a vacuum state. A temperature control device is used to maintain the temperature of the second chamber 124 at the desorption temperature; A gas device is used to evacuate the second chamber 124 until the pressure inside the second chamber 124 becomes constant and no longer decreases, thus completing the desorption process of the sample to be tested.

[0090] S104, initial XRD characterization and physical adsorption characterization A temperature control device is used to keep the temperature of the second chamber constant at the adsorption temperature T2; Record the initial state of the gas supply chamber in the gas supply device: temperature T1, volume V0, and pressure P1. Measure and record the dead volume V1, where the dead volume V1 refers to the total volume in the inner tube, the first pipeline 9, and the second chamber excluding the volume occupied by the sample to be tested; Open the valve at the connection between the gas supply chamber and the inner pipe to supply the adsorbed gas in the gas supply chamber to the second chamber through the inner pipe and the first pipe 9; after the system pressure stabilizes, turn on the X-ray source 6 and the X-ray detector 7 to obtain the XRD pattern; then record the pressure P1` and calculate the initial adsorption amount according to the formula. The stable pressure value of the system means that the pressure values ​​of the air supply chamber, the inner pipe, the first pipeline 9, and the second chamber are the same and no longer change.

[0091] Among them, the initial adsorption amount The calculation formula is as follows: ,

[0092] .

[0093] S105, second XRD characterization and physical adsorption characterization Before adsorption, the amount of adsorbed gas in the system was: ; When the valve is closed, the gas supply device starts to supply gas to the gas supply chamber, increasing the pressure in the gas supply chamber to P2. At this point, the amount of adsorbed gas in the system before the second adsorption occurs is n1'.

[0094] .

[0095] After opening the valve and waiting for the system pressure to stabilize again, turn on the X-ray source 6 and X-ray detector 7 to obtain the XRD pattern; then record the pressure P2` and calculate the second adsorption amount according to the formula. .

[0096] Second adsorption amount The calculation formula is as follows: .

[0097] S106, subsequent XRD characterization and physical adsorption characterization Repeat the above process, performing the 3rd, 4th, ... i-th XRD characterization and physisorption characterization sequentially; when the i-th operation is performed, close the control valve and supply gas to the gas supply chamber, increasing its pressure to... Then, the equilibrium pressure of the system is calculated; after the control valve is opened, the actual measured system pressure is completely consistent with the calculated equilibrium pressure and remains unchanged without any downward trend. Then the sample has reached adsorption saturation and is recorded as the last adsorption. The amount of adsorption at the i-th time The calculation formula is as follows: .

[0098] At this point, the total adsorption capacity of the sample can be calculated. .

[0099] Among them, total adsorption amount The calculation formula is as follows: .

[0100] In steps S103 to S106, the second vacuum device and the temperature control device operate continuously throughout the process: the second vacuum device continuously evacuates the first chamber, keeping the first chamber in a vacuum state throughout the entire desorption and adsorption characterization process; the temperature control device continuously maintains the temperature of the second chamber and the first heat exchange medium at the preset adsorption temperature T2.

[0101] Those skilled in the art will understand that although some embodiments herein include certain features included in other embodiments but not others, combinations of features from different embodiments are intended to be within the scope of this application and form different embodiments. For example, any of the claimed embodiments in the claims of this application can be used in any combination.

[0102] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will all fall within the scope of protection of the present invention.

Claims

1. An in-situ characterization device for XRD-physical adsorption, characterized in that, The in-situ characterization device includes: X-ray diffractometer (100), the X-ray diffractometer (100) includes an X-ray source (6), an X-ray detector (7) and an in-situ cell (1), the in-situ cell (1) includes a first housing assembly (11), a second housing assembly (12) and a sample cell assembly (13), the first housing assembly (11) includes a first housing (111), a cover plate (112) and a first window (113), the cover plate (112) is disposed on one side of the first housing (111) along a first direction and has a window thereon; the first window (113) is installed at the window, the cover plate (112), the first window (113) and the first housing (111) together form a sealed first chamber (114); the X-ray source (6) and X-ray detector (7) are used to form a first housing ... The detectors (7) are located on both sides of the first window (113) along the second direction; the second housing assembly (12) is disposed in the first chamber (114) and includes a second housing (121) and a second window (122). The second window (122) is disposed on the side of the second housing (121) along the first direction near the cover plate (112) and together with the second housing (121) forms a sealed second chamber (124); the sample cell assembly (13) is disposed in the second chamber (124) and has a sample slot (1321) opened on the side of it along the first direction near the second window (122); the second housing (121) is provided with a first connection port communicating with the second chamber (124); A physical adsorption apparatus, the physical adsorption apparatus including a gas device, the gas device being connected to the first connection port; A temperature control device, the temperature control device being configured to adjust the temperature of the second chamber (124); Wherein, the first direction and the second direction are perpendicular to each other.

2. The in-situ characterization device according to claim 1, characterized in that, The second window (122) is hemispherical; The cover plate (112) has a semi-circular cross-section on the first reference surface formed by the first direction and the second direction; the outline of the window is adapted to the cross-sectional outline of the cover plate (112) on the first reference surface. The orthographic projection of the first window (113) onto the first reference plane covers a portion of the orthographic projection of the second window (122) onto the first reference plane, and the center lines of the two projections are collinear.

3. The in-situ characterization device according to claim 2, characterized in that, The second window panel (122) has an ear plate (1221) at its edge, the ear plate (1221) surrounding the second window panel (122) circumferentially; and The second housing (121) includes a tablet assembly (123), which includes a first connecting seat (1231) and a tablet (1232). The first connecting seat (1231) is sleeved on the outside of the sample cell assembly (13) and is disposed on the side of the second housing (121) close to the cover plate (112) along the first direction. The tablet (1232) is disposed on the side of the first connecting seat (1231) away from the second housing (121) along the first direction, and the ear plate (1221) is pressed between the tablet (1232) and the first connecting seat (1231).

4. The in-situ characterization device according to claim 3, characterized in that, The first connecting seat (1231) is provided with a first flow channel (12311), and its outer wall is provided with a first inlet and a first outlet communicating with the first flow channel (12311); and The temperature control device includes a constant temperature device, the inlet and outlet of which are respectively connected to the first inlet and the first outlet.

5. The in-situ characterization device according to claim 4, characterized in that, The gas device includes: Gas supply device and first air extraction device; Pipe assembly (2), one end of which is connected to the first connection port, and the other end is connected to the gas supply device and the first air extraction device respectively.

6. The in-situ characterization device according to claim 5, characterized in that, The pipe assembly (2) includes an outer pipe (21) and an inner pipe (22) disposed inside the outer pipe (21). One end of the inner pipe (22) extends to the outside of the outer pipe (21) and communicates with the first connection port, and the other end extends to the outside of the outer pipe (21) and communicates with the gas supply device and the first air extraction device respectively. There is a gap between the inner wall of the outer pipe (21) and the outer wall of the inner pipe (22). The outer pipe (21) is provided with a second inlet and a second outlet communicating with the gap. The second inlet communicates with the inlet end of the thermostat, and the second outlet communicates with the first inlet on the first connecting seat (1231). The first outlet on the first connecting seat (1231) communicates with the outlet end of the thermostat.

7. The in-situ characterization device according to claim 6, characterized in that, The section of the inner tube (22) located inside the outer tube (21) is a corrugated pipe.

8. The in-situ characterization device according to claim 1, characterized in that, The in-situ pool (1) also includes: A first anti-scattering baffle (14) is disposed in the first chamber (114) and located on the side of the second window (122) close to the cover plate (112) along the first direction; the first anti-scattering baffle (14) has an opening (141) adapted to the outer contour of the second window (122) on the side of the first anti-scattering baffle (14) close to the second window (122) along the first direction; the first anti-scattering baffle (14) is parallel to the second reference surface formed by the first direction and the third direction; A second anti-scattering baffle (15) is disposed in the second chamber (124) and located on the side of the sample cell assembly (13) close to the second window (122) along the first direction; the second anti-scattering baffle (15) is arranged parallel to the first anti-scattering baffle (14) and spaced apart along the second direction; the orthographic projection of the second anti-scattering baffle (15) on the second reference plane covers a portion of the orthographic projection of the first anti-scattering baffle (14) on the second reference plane and at least a portion of the orthographic projection of the clearance opening (141) on the second reference plane; and The X-ray source (6) is located on the side of the first anti-scattering baffle (14) away from the second anti-scattering baffle (15) along the second direction; the X-ray detector (7) is located on the side of the second anti-scattering baffle (15) away from the first anti-scattering baffle (14) along the second direction. Wherein, the third direction is perpendicular to both the first direction and the second direction.

9. The in-situ characterization device according to claim 8, characterized in that, The second housing (121) is provided with a first positioning structure, and the first anti-scattering baffle (14) is provided with a second positioning structure that positions and cooperates with the first positioning structure; The sample cell assembly (13) is provided with a third positioning structure; the second anti-scattering baffle (15) is provided with a fourth positioning structure that is positioned and cooperates with the third positioning structure.

10. The in-situ characterization device according to claim 9, characterized in that, The first positioning structure is a first positioning groove, and the second positioning structure is a first positioning protrusion; or the first positioning structure is a first positioning protrusion, and the second positioning structure is a first positioning groove. The third positioning structure is the second positioning groove, and the fourth positioning structure is the second positioning protrusion; or the third positioning structure is the second positioning protrusion, and the fourth positioning structure is the second positioning groove.

11. The in-situ characterization device according to claim 1, characterized in that, The sample cell assembly (13) includes: The first pool body (131) is disposed in the second chamber (124), and a first connecting structure is provided on the side of the first direction close to the second window (122); The second pool (132) is disposed in the second chamber (124). The sample groove (1321) is disposed on the side of the second window (122) along the first direction and the second connecting structure that cooperates with the first connecting structure is disposed on the side of the second window (122) along the first direction away from the second window (122).

12. The in-situ characterization device according to claim 11, characterized in that, The second pool body (132) is provided with a positioning mark. The positioning mark is set along the outline of the orthographic projection of the first window (113) onto the second pool body (132) in the first direction, so as to define the marking area enclosed by the positioning mark and the surrounding area outside the marking area on the second pool body (132).

13. The in-situ characterization device according to claim 11, characterized in that, The first connecting structure is a connecting protrusion, and the second connecting structure is a connecting groove; or The first connecting structure is a connecting groove (1312), and the second connecting structure is a connecting protrusion (1322).

14. The in-situ characterization device according to claim 13, characterized in that, The outer wall of the first pool body (131) is provided with a first connecting hole (1313), and the first connecting structure is provided with a second connecting hole (1314) communicating with the first connecting hole (1313). The second connecting hole (1314) penetrates the second connecting structure along the first direction and communicates with the sample groove (1321); and / or The second pool body (132) has a third connecting hole (1323) on its pool wall that communicates with the sample tank (1321).

15. The in-situ characterization device according to claim 14, characterized in that, A filter element is provided in the second connection hole (1314) and / or the third connection hole (1323).

16. The in-situ characterization device according to claim 1, characterized in that, The temperature control device includes a heating device and a cooling device. The heating device includes a heating element and a temperature sensing element. The temperature sensing element's measuring head passes through the second housing (121) and is disposed on the sample cell assembly (13). The second housing (121) includes a heat-conducting block (1212) and an inner shell (1213). The heat-conducting block (1212) and the inner shell (1213) are sequentially arranged on the side of the first chamber (114) away from the cover plate (112) along the first direction. The heat-conducting block (1212) is provided with a second flow channel (12121) and a heating channel (12122) inside. The outer wall of the heat-conducting block (1212) is provided with a third inlet (12123) and a third outlet (12124) communicating with the second flow channel (12121). The third inlet (12123) is connected to the cooling device, and the third outlet (12124) is connected to the outside of the first housing assembly (11). The heating element is provided in the heating channel (12122). The inner shell (1213) is provided with a first connection port communicating with the second chamber (124). The first connection port is connected to the gas device.

17. The in-situ characterization device according to claim 16, characterized in that, The first housing (111) is provided with a first interface (11111), a second interface (11112), a third interface (11113), and a fourth interface (11114) communicating with the first chamber (114); and The first connection port is connected to the gas device through the first interface (11111); The third inlet (12123) is connected to the cooling device through the second interface (11112), and the third outlet (12124) is connected to the third interface (11113); The wiring of both the heating element and the temperature detection element passes through the fourth interface (11114) and is connected to the heating control element in the temperature control device.

18. The in-situ characterization device according to claim 1, characterized in that, The in-situ characterization device further includes a second suction device; and a fifth interface (11115) is provided on the first housing (111) communicating with the first chamber (114), the fifth interface (11115) communicating with the second suction device; and / or The X-ray diffractometer (100) also includes a lifting device (3), the output end of which is provided with the in-situ cell (1) to drive the in-situ cell (1) to move along the first direction.

19. A characterization method using the in-situ characterization apparatus according to any one of claims 1-18, characterized in that, The characterization method includes: The sample to be tested is placed into the sample slot (1321), and multiple vent holes are processed in the first detection area of ​​the sample to be tested using a perforating tool; then the second detection area of ​​the sample to be tested is flattened; wherein the first detection area is the area of ​​the sample surface not covered by the orthographic projection of the first window (113) in the first direction, and the second detection area is the area of ​​the sample surface covered by the orthographic projection of the first window (113) in the first direction; The temperature of the second chamber (124) is kept constant to the desorption temperature using the temperature control device. Then, the second chamber (124) is evacuated using a gas device until the pressure inside the second chamber (124) is constant and no longer changes, thus completing the desorption process of the sample to be tested. The temperature of the second chamber (124) is kept constant at the adsorption temperature using the temperature control device. Then, the first molar amount of adsorption gas is introduced into the second chamber (124) using the gas device. After the pressure value in the second chamber (124) stabilizes, the X-ray source (6) and X-ray detector (7) are turned on to obtain the XRD pattern and measure the adsorption amount of the sample. Next, the gas device is started to continue to introduce the second molar amount of the adsorbed gas into the second chamber (124). After the pressure stabilizes again, the X-ray source (6) and X-ray detector (7) are turned on again to obtain the XRD pattern and measure the adsorption amount of the sample. The above process is repeated until the pressure no longer changes after the adsorbed gas is introduced.

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