Absorption spectrum in-situ characterization pool and method for acquiring transient absorption spectrum based on characterization pool

Abstract

The invention provides an absorption spectrum in-situ characterization pool and a method for obtaining a transient absorption spectrum based on the characterization pool, and relates to the field of absorption spectrum characterization, the characterization pool comprises a main body part and a cover body which are in sealed connection, the main body part and the cover body jointly form a closed cavity, the closed cavity is used for accommodating a to-be-detected sample and maintaining the atmosphere and pressure in the pool, the characterization cell comprises a gas channel, the gas channel comprises a gas channel inlet and a gas channel outlet which are formed in the main body part, and the gas channel inlet and the gas channel outlet penetrate through the main body part and are communicated with the closed cavity; the heating module is fixed on the cover body and extends into the closed cavity; the back pressure module is connected with the gas path outlet; and the optical path comprises a first light window and a second light window which are arranged on two opposite sides of the main body part. By arranging the gas passage, the back pressure module and the heating module, the atmosphere, the temperature and the pressure intensity in the testing process can be controlled, so that richer testing conditions are provided for in-situ characterization of the absorption spectrum.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of absorption spectroscopy characterization, and specifically, to an absorption spectroscopy in-situ characterization cell and a method for obtaining a transient absorption spectrum based on the characterization cell. Background Art

[0002] Transient absorption spectroscopy is a common pump-probe dual-beam characterization technique capable of ultrahigh temporal resolution on the femtosecond scale. It is used to study the dynamics of excited states (e.g., electrons, excitons, and polarons) in materials following photoexcitation. It is a core characterization tool in the fields of photophysics and photochemistry. By probing the dynamic changes in the absorbance of a sample following pump light excitation, it reveals ultrafast processes such as relaxation of excited states, energy transfer, and interfacial charge transfer. It is widely used in research on solar cells, semiconductor photocatalysis, and quasiparticle coupling in condensed matter physics.

[0003] However, although transient absorption spectroscopy technology has been developed for more than half a century, its characterization conditions in the field of photocatalysis are mostly still limited to room temperature and pressure. This greatly limits its research on photocatalytic carrier dynamics. In particular, in recent years, multi-energy coupling catalysis research has gradually emerged, and the synergistic effect of multiple energies is more conducive to the realization of high conversion rate and high selectivity in the catalytic reaction process. These chemical reactions need to be carried out at a certain temperature and pressure, such as photothermal coupled catalytic green ammonia synthesis and methanol hydrogen production reaction. For these photochemical reactions, the transient absorption spectroscopy characterization results obtained at room temperature and pressure can only characterize the intrinsic information of the material, which is far from describing the real carrier dynamics in the system. Therefore, there is an urgent need in this field to develop an absorption spectroscopy in situ characterization cell suitable for different temperatures, pressures and atmospheres to meet the needs of temperature and pressure control in the test. Summary of the Invention

[0004] The embodiments of the present application provide an in-situ absorption spectrum characterization cell and a method for obtaining transient absorption spectra based on the characterization cell, aiming to solve the problem of how to meet the absorption spectrum condition requirements of different temperatures, pressures and atmospheres in the test.

[0005] In a first aspect, an embodiment of the present application provides an absorption spectroscopy in-situ characterization cell, the characterization cell comprising a main body and a cover body that are sealed together, the main body and the cover body together forming a closed cavity, the closed cavity being used to accommodate a sample to be tested and maintain the atmosphere and pressure within the cell, the characterization cell comprising: a gas passage, the gas passage comprising a gas passage inlet and a gas passage outlet provided on the main body, the gas passage inlet and the gas passage outlet penetrating the main body and communicating with the closed cavity, the characterization cell introducing and exhausting gas through the gas passage inlet and the gas passage outlet to adjust the atmosphere in the closed cavity; a heating module, the heating module being fixed to the cover and extending into the closed cavity, the heating module being configured to carry the sample to be tested and adjust the temperature of the sample to be tested to a first preset value; a back pressure module, the back pressure module being connected to the gas path outlet and configured to adjust the pressure in the closed cavity to a second preset value; An optical pathway comprises a first light window and a second light window disposed on opposite sides of the main body, wherein the first light window is configured to provide a pathway for pulsed injection of the sample to be tested into the characterization pool, and the second light window is configured to provide a pathway for pulsed injection out of the characterization pool.

[0006] In an optional embodiment, the main body includes a bottom plate and a plurality of side plates circumferentially arranged around the bottom plate, the bottom plate is arranged opposite to the cover body, and the plurality of side plates are arranged between the bottom plate and the cover body; The air path inlet and the air path outlet pass through the side plate and are in communication with the closed cavity.

[0007] In an optional embodiment, the plurality of side panels include a first side panel and a second side panel that are oppositely arranged, and the first light window and the second light window are respectively embedded in the first side panel and the second side panel; The orthographic projections of the first light window and the second light window on the first side panel respectively at least partially overlap with the orthographic projections of the sample to be tested on the first side panel.

[0008] In an optional embodiment, a coolant circulation passage is integrated in the main body, and the main body realizes circulation temperature control of the closed cavity through the coolant circulation passage, wherein the main body includes a coolant inlet and a coolant outlet, and the coolant inlet and the coolant outlet are connected to the coolant circulation passage in the main body.

[0009] In an optional embodiment, the heating module includes two symmetrically arranged heating sub-modules, and the sample to be tested is clamped between the two heating sub-modules.

[0010] In an optional embodiment, the characterization pool further includes a temperature measurement module, which is disposed between the heating submodules. The temperature measurement module passes through the cover and contacts the sample to be tested, and is configured to obtain the temperature of the sample to be tested in real time.

[0011] In an optional embodiment, the first preset value is greater than or equal to 25°C and less than or equal to 300°C.

[0012] In an optional embodiment, the atmosphere introduced into the closed cavity includes at least one of the following: nitrogen, oxygen, air, alkane gas, carbon dioxide, hydrogen, methanol, ethanol, water vapor, ammonia, benzene, formaldehyde, ethylene, and carbon monoxide.

[0013] In an optional embodiment, the second preset value is greater than or equal to 1 bar and less than or equal to 3 bar.

[0014] A second aspect of the embodiments of the present application provides a method for obtaining a transient absorption spectrum based on a characterization cell, wherein the characterization cell is an absorption spectrum in-situ characterization cell as described in any one of the first aspects of the embodiments of the present application, and the method comprises: Placing the sample to be tested into the closed cavity of the characterization cell, adjusting the atmosphere of the closed cavity of the characterization cell to the target atmosphere through the gas inlet and the gas outlet, and controlling the back pressure module to adjust the pressure of the closed cavity to a second preset value; Controlling the heating module to adjust the temperature of the sample to be tested to a first preset value; injecting a pump pulse into the sample to be tested in the closed cavity through the first light window to excite the sample to be tested; After a preset delay, a detection pulse is emitted from the first light window toward the excited sample to be tested, so that the detection pulse is modulated by the excited sample to be tested to form a target pulse; The target pulse emitted through the second light window is captured by a spectrometer, and a transient absorption spectrum of the sample to be tested is generated.

[0015] Beneficial effects: The present application provides an absorption spectrum in-situ characterization cell and a method for obtaining a transient absorption spectrum based on the characterization cell. The characterization cell includes a main body and a cover body that are sealed and connected. The main body and the cover body together constitute a closed cavity. The closed cavity is used to accommodate a sample to be tested and maintain the atmosphere and pressure in the cell. The characterization cell includes: a gas passage, the gas passage includes a gas passage inlet and a gas passage outlet provided in the main body, the gas passage inlet and the gas passage outlet pass through the main body and communicate with the closed cavity, and the characterization cell introduces and exhausts gas through the gas passage inlet and the gas passage outlet to adjust the atmosphere in the closed cavity; a heating module, The heating module is fixed on the cover and extends into the closed cavity, and the heating module is configured to carry the sample to be tested and adjust the temperature of the sample to be tested to a first preset value; the back pressure module is connected to the gas outlet, and the back pressure module is configured to adjust the pressure in the closed cavity to a second preset value; the optical path includes a first light window and a second light window provided on opposite sides of the main body, the first light window is configured to provide a path for pulsed injection of the sample to be tested in the characterization pool, and the second light window is configured to provide a path for pulsed injection out of the characterization pool. By providing a gas path, a back pressure module and a heating module in the characterization pool, the present application can control the atmosphere, temperature and pressure of the sample to be tested during the test process, thereby providing richer test conditions for the in-situ characterization of the absorption spectrum of the sample to be tested, greatly expanding the application scope of transient absorption spectroscopy in the fields of photocatalysis and multi-energy coupling catalysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the description of the embodiments of the present application. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0017] Figure 1 This is a schematic structural diagram of an absorption spectroscopy in-situ characterization cell proposed in one embodiment of the present application; Figure 2 This is a transmission-type in-situ transient absorption spectrum of anatase titanium dioxide film corresponding to different delay times at room temperature and pressure proposed in one embodiment of the present application; Figure 3 This is a transmission-type in-situ transient absorption kinetics curve of anatase titanium dioxide film corresponding to different detection wavelengths at room temperature and pressure proposed in one embodiment of the present application; Figure 4 This is a transmission-type in-situ transient absorption kinetics curve of anatase titanium dioxide film at normal pressure and different temperatures proposed in one embodiment of the present application; Figure 5 This is a transmission-type in-situ transient absorption kinetics curve of anatase titanium dioxide film at 300° C. and different pressures proposed in one embodiment of the present application.

[0018] Explanation of the accompanying symbols: 1. Air path inlet; 2. Cooling liquid inlet; 3. Cooling liquid outlet; 4. Air path outlet; 5. Heating module; 6. Sample to be tested; 7. Temperature measurement module; 8. Back pressure module; 9. Main body; 10. Cover; 11. Closed cavity. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0020] In the drawings, the sizes of components, layer thicknesses, or regions may be exaggerated for clarity. Therefore, any implementation of the present disclosure is not necessarily limited to the dimensions shown in the drawings, and the shapes and sizes of components in the drawings do not reflect true proportions. Furthermore, the drawings schematically illustrate idealized examples, and any implementation of the present disclosure is not limited to the shapes or values shown in the drawings.

[0021] Transient absorption spectroscopy is a common pump-probe dual-beam characterization technique capable of ultrahigh temporal resolution on the femtosecond scale. It is used to study the dynamics of excited states (e.g., electrons, excitons, and polarons) in materials following photoexcitation. It is a core characterization tool in the fields of photophysics and photochemistry. By probing the dynamic changes in the absorbance of a sample following pump light excitation, it reveals ultrafast processes such as relaxation of excited states, energy transfer, and interfacial charge transfer. It is widely used in research on solar cells, semiconductor photocatalysis, and quasiparticle coupling in condensed matter physics.

[0022] However, although transient absorption spectroscopy technology has been developed for more than half a century, its characterization conditions in the field of photocatalysis are mostly still limited to room temperature and pressure. This greatly limits its research on photocatalytic carrier dynamics. In particular, in recent years, research on multi-energy coupled catalysis has gradually emerged, and the synergistic effect of multiple energies is more conducive to the realization of high conversion rate and high selectivity in the catalytic reaction process. These chemical reactions need to be carried out at a certain temperature and pressure, such as photothermal coupled catalytic green ammonia synthesis and methanol hydrogen production reaction. For these photochemical reactions, the transient absorption spectroscopy characterization results obtained at room temperature and pressure can only characterize the intrinsic information of the material, and are far from describing the actual carrier dynamics in the system. Therefore, it is urgent to develop an absorption spectroscopy in situ characterization cell suitable for high temperature and high pressure, which can simultaneously meet the requirements of temperature and pressure control in the test, making it possible to study the carrier dynamics and interfacial charge transfer process of multi-energy coupled catalysts in situ, thereby clarifying the photophysical process and photochemical reaction mechanism, and providing basic guidance for the development of efficient multi-energy coupled catalysts.

[0023] In view of this, the present invention proposes an absorption spectroscopy in-situ characterization cell. Figure 1 FIG. 1 shows a schematic structural diagram of an absorption spectrum in-situ characterization cell proposed in one embodiment of the present application. Figure 1 As shown, the characterization cell includes a main body 9 and a cover 10 that are sealed and connected. The main body 9 and the cover 10 together form a closed cavity 11. The closed cavity 11 is used to accommodate the sample 6 to be tested and maintain the atmosphere and pressure in the cell.

[0024] In an embodiment of the present application, the characterization pool includes: a gas passage, the gas passage including a gas passage inlet 1 and a gas passage outlet 4 arranged on the main body 9, the gas passage inlet 1 and the gas passage outlet 4 pass through the main body 9 and are connected to the closed cavity 11, the gas passage inlet 1 is used to introduce gas into the closed cavity 11 of the characterization pool, and the gas passage outlet 4 is used to discharge the gas in the closed cavity 11 of the characterization pool, and the characterization pool introduces and discharges gas through the gas passage inlet 1 and the gas passage outlet 4 to adjust the atmosphere in the closed cavity.

[0025] In some optional embodiments, the main body 9 includes a bottom plate and a plurality of side plates circumferentially arranged around the bottom plate, the bottom plate is arranged opposite to the cover body 10, and the plurality of side plates are arranged between the bottom plate and the cover body 10; the air path inlet 1 and the air path outlet 4 pass through the side plates and are connected to the closed cavity 11.

[0026] Optionally, the gas path inlet 1 and the gas path outlet 4 may be provided on the same side panel of the main body 9 , or the gas path inlet 1 and the gas path outlet 4 may be provided on different side panels of the main body 9 .

[0027] In some optional embodiments, the gas atmosphere introduced into the closed cavity includes common gases and special gases. Optionally, the atmosphere introduced into the closed cavity includes at least one of the following: nitrogen, oxygen, air, alkane gas, carbon dioxide, hydrogen, methanol, ethanol, water vapor, ammonia, benzene, formaldehyde, ethylene, and carbon monoxide.

[0028] The embodiment of the present application provides the required target atmosphere into the closed cavity 11 by arranging the gas path inlet 1 and the gas path outlet 4 located on the main body 9. Therefore, during the absorption spectrum test of the sample to be tested, the characterization cell can place the sample to be tested 6 in different target atmospheres according to the test requirements, greatly expanding the application scope of transient absorption spectroscopy in the fields of photocatalysis and multi-energy coupling catalysis.

[0029] In the embodiment of the present application, the characterization cell further includes a back pressure module 8, which is connected to the gas outlet 4 and is configured to adjust the pressure in the closed cavity 11 to a second preset value. The back pressure module 8 is used to adjust the gas flow rate of the gas outlet 4, close the gas outlet 4 when the pressure in the closed cavity 11 is less than the second preset value, and increase the gas flow rate of the gas outlet 4 when the pressure in the closed cavity 11 is greater than the second preset value, so that the pressure in the closed cavity 11 is adjusted to the second preset value, thereby providing different pressure requirements for the absorption spectrum test process of the sample to be tested 6, so that the characterization cell can test the sample to be tested under different pressure conditions.

[0030] In some optional embodiments, the second preset value is greater than or equal to 1 bar and less than or equal to 3 bar.

[0031] In the embodiment of the present application, the characterization cell further includes a heating module 5, which is fixed to the cover 10 and extends into the enclosed cavity 11. The heating module 5 is configured to support the sample 6 and adjust the temperature of the sample 6 to a first preset value. The present application uses the heating module 5 to provide different temperature requirements for the sample 6 during the absorption spectrum test process, allowing the characterization cell to test the sample under different temperature conditions.

[0032] In some optional embodiments, the heating module 5 includes two symmetrically arranged heating submodules, the sample 6 to be tested is sandwiched between the two heating submodules, and a gap exists between the sample 6 to be tested and the inner wall of the cover 10. Optionally, a fixing groove is provided on the surface of the heating submodule on the side in contact with the sample 6 to be tested, and the heating submodule fixes the sample 6 to be tested via the fixing groove. To ensure the bearing capacity of the heating submodule for the sample 6 to be tested, the size of the fixing groove matches the size of the sample 6 to be tested.

[0033] In some optional embodiments, the heating submodule is further provided with a fastener, which passes through the heating submodule and is arranged corresponding to the fixing groove. The heating submodule presses and fixes the sample to be tested 6 between the heating submodules through the fastener.

[0034] In some optional embodiments, the characterization pool further includes a temperature measurement module 7, the orthographic projection of the temperature measurement module 7 on the base plate is located between the orthographic projections of the symmetrically arranged heating sub-modules on the base plate, the temperature measurement module 7 passes through the cover body 10 and contacts the sample to be tested 6, and the temperature measurement module is configured to obtain the temperature of the sample to be tested 6 in real time, so that the heating module 5 adjusts the temperature of the sample to be tested 6 when the temperature of the sample to be tested 6 is inconsistent with the first preset value.

[0035] In some optional embodiments, the first preset value is greater than or equal to 25°C and less than or equal to 300°C.

[0036] In some optional embodiments, in order to maintain the temperature of each side plate of the main body 9 in the characterization pool from being too high, to avoid safety accidents and to maintain air tightness, a cooling liquid circulation passage is integrated in the main body 9, and the main body 9 adjusts the temperature of the side plates of the closed cavity 11 through the cooling liquid circulation passage, so that the temperature of the side plates of the closed cavity 11 is not too high. Specifically, the cooling liquid circulation passage is integrated in the main body 9, and the cooling liquid circulation passage is arranged on each side plate of the main body 9. The side plates of the closed cavity 11 are cooled through the cooling liquid circulation passage to prevent the side plates of the main body 9 from overheating during the sample characterization process, affecting the air tightness of the characterization pool and causing safety hazards. The main body 9 includes a cooling liquid inlet 2 and a cooling liquid outlet 3, and the cooling liquid inlet 2 and the cooling liquid outlet 3 are connected to the cooling liquid circulation passage in the main body 9. The cooling liquid flows into the cooling liquid circulation passage from the cooling liquid inlet 2 and flows out from the cooling liquid outlet 3 after passing through the cooling liquid circulation passage.

[0037] Optionally, the coolant inlet 2 and the coolant outlet 3 can be arranged on the same side panel of the main body 9, and the coolant inlet 2 and the coolant outlet 3 can also be arranged on different side panels of the main body 9; the height of the coolant inlet 2 relative to the bottom plate can be greater than the height of the coolant outlet 3 relative to the bottom plate, and the height of the coolant inlet 2 relative to the bottom plate can also be less than the height of the coolant outlet 3 relative to the bottom plate.

[0038] In the embodiment of the present application, the characterization cell further includes an optical path, wherein the optical path includes a first light window and a second light window ( Figure 1 ), the first light window is configured to provide a path for pulse injection into the sample to be tested 6 in the characterization pool, and the second light window is configured to provide a path for pulse injection out of the characterization pool. Wherein, the multiple side panels of the main body 9 include a first side panel and a second side panel arranged opposite to each other, and the first light window and the second light window are respectively embedded in the first side panel and the second side panel; in order to ensure that the first light window can make the pulse excite the sample to be tested 6, and make the pulse modulated by the excited sample to be tested 6 be emitted from the second light window, the orthographic projections of the first light window and the second light window on the first side panel respectively overlap with the orthographic projections of the sample to be tested 6 on the first side panel, and further, the central axes of the first light window and the second light window are aligned with the sample to be tested 6.

[0039] In some optional embodiments, to expand the detection wavelength range of the test process, so that the absorption spectrum test of the test sample can support systematic research on related catalytic reactions within a wide wavelength band and provide rich kinetic information for clarifying the reaction mechanisms of photocatalysis and multi-energy coupled catalysis, the materials of the first and second light windows can be adjusted to selectively transmit light within a target wavelength range. Optionally, the target wavelength range includes ultraviolet light, visible light, and near-infrared light.

[0040] The present application provides an absorption spectrum in-situ characterization cell and a method for obtaining a transient absorption spectrum based on the characterization cell. The characterization cell includes a main body and a cover body that are sealed and connected. The main body and the cover body together constitute a closed cavity. The closed cavity is used to accommodate a sample to be tested and maintain the atmosphere and pressure in the cell. The characterization cell includes: a gas passage, the gas passage includes a gas passage inlet and a gas passage outlet provided in the main body, the gas passage inlet and the gas passage outlet pass through the main body and communicate with the closed cavity, and the characterization cell introduces and exhausts gas through the gas passage inlet and the gas passage outlet to adjust the atmosphere in the closed cavity; a heating module, The heating module is fixed on the cover and extends into the closed cavity, and the heating module is configured to carry the sample to be tested and adjust the temperature of the sample to be tested to a first preset value; the back pressure module is connected to the gas outlet, and the back pressure module is configured to adjust the pressure in the closed cavity to a second preset value; the optical path includes a first light window and a second light window provided on opposite sides of the main body, the first light window is configured to provide a path for pulsed injection of the sample to be tested in the characterization pool, and the second light window is configured to provide a path for pulsed injection out of the characterization pool. By providing a gas path, a back pressure module and a heating module in the characterization pool, the present application can control the atmosphere, temperature and pressure of the sample to be tested during the test process, thereby providing richer test conditions for the in-situ characterization of the absorption spectrum of the sample to be tested, greatly expanding the application scope of transient absorption spectroscopy in the fields of photocatalysis and multi-energy coupling catalysis.

[0041] Based on the same inventive concept, an embodiment of the present application discloses a method for obtaining a transient absorption spectrum based on a characterization cell, wherein the characterization cell is the in-situ absorption spectrum characterization cell described in the embodiment of the present application, and the method includes: placing the sample to be tested into the closed cavity of the characterization cell, adjusting the atmosphere of the closed cavity of the characterization cell to the target atmosphere through the gas path inlet and the gas path outlet, and controlling the back pressure module to adjust the pressure of the closed cavity to a second preset value; controlling the heating module to adjust the temperature of the sample to be tested to a first preset value; injecting a pump pulse into the sample to be tested in the closed cavity through the first light window to excite the sample to be tested; after a delay of a preset time, injecting a detection pulse from the first light window into the excited sample to be tested, so that the detection pulse is modulated by the excited sample to be tested to form a target pulse; capturing the target pulse emitted through the second light window based on a spectrometer, and generating a transient absorption spectrum of the sample to be tested.

[0042] The embodiment of the present application can test the sample to be tested under different test environmental conditions (such as different pressures, temperatures, atmospheres, etc.) through the characterization cell, and use multi-time-scale absorption spectroscopy to perform in situ characterization of photocatalysts and multi-energy coupled catalysts, which greatly expands the application scope of transient absorption spectroscopy in the field of photocatalysis and multi-energy coupled catalysis.

[0043] Figure 2 The transmission in-situ transient absorption spectra of anatase titanium dioxide thin film corresponding to different delay times at room temperature and pressure according to an embodiment of the present application are shown. Figure 2 As shown, based on the characterization cell provided in the embodiment of the present application, the in-situ transient absorption spectrum of the sample to be tested (anatase titanium dioxide film) can be tested, and the sample to be tested can be obtained at room temperature and pressure after delaying different preset times (such as Figure 2 The transient spectra of 1ps, 500ps and 5ns shown in the figure indicate that the characterization cell according to the embodiment of the present application can be used to test the sample under normal temperature and pressure and obtain accurate test results. The obtained transient absorption spectrum has a high signal-to-noise ratio, which meets the requirements for the detection of multi-time-scale transient spectra.

[0044] Figure 3 The transmission-type in-situ transient absorption kinetics curves of anatase titanium dioxide thin film corresponding to different detection wavelengths at room temperature and pressure according to an embodiment of the present application are shown. Figure 3 As shown, based on the characterization cell provided in the embodiment of the present application, the in-situ transient absorption spectrum of the sample to be tested (anatase titanium dioxide film) is tested. By changing the light window material, the transient absorption spectrum of the sample to be tested at different detection wavelengths (such as Figure 3 The transient absorption kinetic curves of the visible light and near-infrared light bands shown in the figure indicate that the embodiment of the present application can obtain accurate test results at different wavelengths for the sample to be tested based on the characterization cell. Under the characterization conditions of normal temperature and pressure, the kinetic curves obtained by testing using the characterization cell described in the embodiment of the present application have a high signal-to-noise ratio and an obvious change trend, thereby expanding the band range demand for transient absorption spectroscopy testing.

[0045] Figure 4 The transmission-type in-situ transient absorption kinetics curves of the anatase titanium dioxide film corresponding to normal pressure and different temperatures proposed in one embodiment of the present application are shown. Figure 4 As shown, based on the characterization cell provided in the embodiment of the present application, the in-situ transient absorption spectrum of the sample to be tested (anatase titanium dioxide film) is tested. By changing the temperature of the characterization cell by the heating module 5, the transient absorption spectrum of the sample to be tested can be obtained at normal pressure, a detection wavelength of 625nm, and different temperatures (such as Figure 4As shown in the transient absorption kinetic curves at room temperature, 100°C, 150°C, 200°C, 250°C and 300°C, under normal pressure, the transient absorption intensity at 625 nm at different temperatures shows clearly discernible differences, indicating that the embodiment of the present application can obtain accurate test results at different temperatures for the sample to be tested based on the characterization cell, thereby expanding the temperature range requirement for transient absorption spectroscopy testing.

[0046] Figure 5 The transmission-type in-situ transient absorption kinetics curve of the anatase titanium dioxide film at 300°C and different pressures proposed in one embodiment of the present application is shown. Figure 5 As shown, based on the characterization cell provided in the embodiment of the present application, the in-situ transient absorption spectrum of the sample to be tested (anatase titanium dioxide film) is tested. By changing the pressure of the characterization cell by the back pressure module 8, the transient absorption spectrum of the sample to be tested can be obtained at 300°C, a detection wavelength of 600nm, and different pressures (such as Figure 5 The transient absorption kinetic curves at 1.0 bar, 2.0 bar and 2.5 bar shown in the figure indicate that the embodiment of the present application can obtain accurate test results at different pressures for the sample to be tested based on the characterization cell, thereby expanding the pressure range requirement for transient absorption spectroscopy testing.

[0047] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0048] In the description of this specification, it should be understood that the terms "center", "thickness", "up", "down", "front", "back", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0049] In this application, unless otherwise expressly specified or limited, terms such as "installed," "connected," "connect," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0050] In this application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature includes the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0051] The above application provides many different embodiments or examples for implementing the different structures of the present application. In order to simplify the present application, the components and settings of specific examples are described above. Of course, these are merely examples and are not intended to limit the present application. In addition, the present application may repeat reference numbers and / or reference letters in different examples. Such repetition is for the purpose of simplicity and clarity and does not in itself indicate the relationship between the various embodiments and / or settings discussed.

[0052] References herein to "one embodiment," "an embodiment," or "one or more embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present application. Furthermore, please note that instances of the phrase "in one embodiment" do not necessarily all refer to the same embodiment.

[0053] In the description provided herein, a large number of specific details are described. However, it is understood that the embodiments of the present application can be practiced without these specific details. In some instances, well-known methods, structures, and techniques are not shown in detail so as not to obscure the understanding of this description.

[0054] Finally, it should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "includes," or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or terminal device that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or elements that are inherent to such process, method, article, or terminal device. In the absence of further restrictions, an element defined by the phrase "comprises a ..." does not exclude the presence of additional identical elements in the process, method, article, or terminal device that includes the element.

[0055] The above is a detailed introduction to an absorption spectrum in-situ characterization cell and a method for obtaining transient absorption spectra based on the characterization cell provided by the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for general technicians in this field, based on the ideas of the present application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. An absorption spectroscopy in-situ characterization cell, characterized in that: The characterization cell comprises a main body and a cover body that are sealed together, and the main body and the cover body together form a closed cavity, and the closed cavity is used to accommodate the sample to be tested and maintain the atmosphere and pressure in the cell. The characterization cell comprises: a gas passage, the gas passage comprising a gas passage inlet and a gas passage outlet provided on the main body, the gas passage inlet and the gas passage outlet penetrating the main body and communicating with the closed cavity, the characterization cell introducing and exhausting gas through the gas passage inlet and the gas passage outlet to adjust the atmosphere in the closed cavity; a heating module, the heating module being fixed to the cover and extending into the closed cavity, the heating module being configured to carry the sample to be tested and adjust the temperature of the sample to be tested to a first preset value; a back pressure module, the back pressure module being connected to the gas path outlet and configured to adjust the pressure in the closed cavity to a second preset value; An optical pathway comprises a first light window and a second light window disposed on opposite sides of the main body, wherein the first light window is configured to provide a pathway for pulsed injection of the sample to be tested into the characterization pool, and the second light window is configured to provide a pathway for pulsed injection out of the characterization pool.

2. The absorption spectroscopy in-situ characterization cell according to claim 1, characterized in that The main body includes a bottom plate and a plurality of side plates arranged around the bottom plate in a circumferential direction, the bottom plate is arranged opposite to the cover body, and the plurality of side plates are arranged between the bottom plate and the cover body; The air path inlet and the air path outlet pass through the side plate and are in communication with the closed cavity.

3. The absorption spectrum in-situ characterization cell according to claim 2, characterized in that The plurality of side panels include a first side panel and a second side panel that are opposite to each other, and the first light window and the second light window are respectively embedded in the first side panel and the second side panel; The orthographic projections of the first light window and the second light window on the first side panel respectively at least partially overlap with the orthographic projections of the sample to be tested on the first side panel.

4. The absorption spectroscopy in-situ characterization cell according to claim 1, characterized in that A coolant circulation passage is integrated in the main body, and the main body realizes circulation temperature control of the closed cavity through the coolant circulation passage, wherein the main body includes a coolant inlet and a coolant outlet, and the coolant inlet and the coolant outlet are connected to the coolant circulation passage in the main body.

5. The absorption spectrum in-situ characterization cell according to claim 1, characterized in that The heating module includes two symmetrically arranged heating submodules, and the sample to be tested is clamped between the two heating submodules.

6. The absorption spectroscopy in-situ characterization cell according to claim 5, characterized in that The characterization cell further includes a temperature measurement module, which is disposed between the heating submodules. The temperature measurement module passes through the cover and contacts the sample to be tested. The temperature measurement module is configured to obtain the temperature of the sample to be tested in real time.

7. The absorption spectrum in-situ characterization cell according to claim 1, characterized in that The first preset value is greater than or equal to 25°C and less than or equal to 300°C.

8. The absorption spectrum in-situ characterization cell according to claim 1, characterized in that The atmosphere introduced into the closed cavity includes at least one of the following: nitrogen, oxygen, air, alkane gas, carbon dioxide, hydrogen, methanol, ethanol, water vapor, ammonia, benzene, formaldehyde, ethylene, and carbon monoxide.

9. The absorption spectrum in-situ characterization cell according to claim 1, characterized in that The second preset value is greater than or equal to 1 bar and less than or equal to 3 bar.

10. A method for obtaining transient absorption spectra based on a characterization cell, characterized in that: The characterization cell is an absorption spectroscopy in-situ characterization cell according to any one of claims 1 to 9, and the method comprises: Placing the sample to be tested into the closed cavity of the characterization cell, adjusting the atmosphere of the closed cavity of the characterization cell to the target atmosphere through the gas inlet and the gas outlet, and controlling the back pressure module to adjust the pressure of the closed cavity to a second preset value; Controlling the heating module to adjust the temperature of the sample to be tested to a first preset value; injecting a pump pulse into the sample to be tested in the closed cavity through the first light window to excite the sample to be tested; After a preset delay, a detection pulse is emitted from the first light window toward the excited sample to be tested, so that the detection pulse is modulated by the excited sample to be tested to form a target pulse; The target pulse emitted through the second light window is captured by a spectrometer, and a transient absorption spectrum of the sample to be tested is generated.

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