A method for preparing a liquid cell in an electron microscope

Abstract

This specification provides a method for preparing a liquid pool for an electron microscope. The method includes: placing a first liquid on a first sheet; covering the first liquid with an intermediate layer; placing a second liquid on the intermediate layer, the intermediate layer separating the first liquid and the second liquid; and placing a second sheet on the second liquid to form a liquid pool comprising the first liquid, the second liquid, the first sheet, the second sheet, and the intermediate layer. This liquid pool enables in-situ observation of liquid reaction processes under an electron microscope.

Description

Technical Field

[0001] This specification relates to the field of device fabrication, and more particularly to a method for preparing a liquid cell for an electron microscope. Background Technology

[0002] With the development of electron microscopy and semiconductor microfabrication technologies, liquid cell technology is also constantly evolving. Liquid cell technology allows nanoscale liquid samples to be enclosed within a liquid cell, enabling the analysis of their structure or composition using electron microscopy. However, existing liquid cell technologies cannot achieve real-time monitoring of reaction processes between different liquids. Therefore, it is necessary to provide a method for preparing a liquid cell that can be used to monitor reaction processes between different liquids. Summary of the Invention

[0003] This specification provides a method for preparing a liquid pool in an electron microscope, the method comprising: placing a first liquid on a first sheet; covering the first liquid with an intermediate layer; placing a second liquid on the intermediate layer, the intermediate layer serving to separate the first liquid and the second liquid; and placing a second sheet on the second liquid to form a liquid pool comprising the first liquid, the second liquid, the first sheet, the second sheet, and the intermediate layer.

[0004] In some embodiments, the first sheet and the second sheet include an electron microscope grid coated with an isolation film.

[0005] In some embodiments, the first sheet and the second sheet are coated with a microporous membrane.

[0006] In some embodiments, the micropore size of the microporous membrane is 100 nm to 10 μm.

[0007] In some embodiments, the intermediate layer does not react with the first solution and the second solution.

[0008] In some embodiments, the intermediate layer comprises an atomically two-dimensional material.

[0009] In some embodiments, the intermediate layer comprises a MoS2 thin film.

[0010] In some embodiments, the thickness of the intermediate layer is less than 2 nm.

[0011] In the embodiments of this specification, a combination of a first layer, a second layer, and an intermediate layer encapsulates the first liquid and the second liquid in two independent parts of a liquid pool. Correspondingly, if the liquid pool is placed in a transmission electron microscope, the intermediate layer undergoes impact damage and irradiation degradation under electron beam irradiation, forming voids. This allows for contact and reaction between the first and second liquids, enabling real-time dynamic observation of the in-situ reaction process using a transmission electron microscope. The technical solution of the embodiments of this specification enables ultra-high resolution in-situ observation under a transmission electron microscope, and can be used for in-situ observation of nanomaterial growth, assembly, etching, and catalytic reaction active sites in a liquid environment. Attached Figure Description

[0012] This specification will be further described by way of exemplary embodiments, which will be described in detail with reference to the accompanying drawings. These embodiments are not limiting; in these embodiments, the same reference numerals denote the same structures, wherein:

[0013] Figure 1 This is an exemplary method for preparing a liquid pool according to some embodiments of this specification.

[0014] Figure 2 This is a schematic diagram of an exemplary liquid tank according to some embodiments of this specification.

[0015] Figure 3 This is a schematic diagram of an exemplary first layer according to some embodiments of this specification. Detailed Implementation

[0016] To more clearly illustrate the technical solutions of the embodiments in this specification, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are merely some examples or embodiments of this specification. For those skilled in the art, these drawings can be applied to other similar scenarios without creative effort. Unless obvious from the context or otherwise specified, the same reference numerals in the drawings represent the same structures or operations.

[0017] It should be understood that the terms “system,” “device,” “unit,” and / or “module” used herein are one way to distinguish different components, elements, parts, sections, or assemblies at different levels. However, if other terms can achieve the same purpose, they may be replaced by other expressions.

[0018] As indicated in this specification and claims, unless the context clearly indicates otherwise, the words "a," "an," "an," and / or "the" do not specifically refer to the singular and may also include the plural. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of expressly identified steps and elements, which do not constitute an exclusive list, and the method or apparatus may also include other steps or elements.

[0019] Flowcharts are used in this specification to illustrate the operations performed by the system according to embodiments of this specification. It should be understood that the preceding or following operations are not necessarily performed in exact order. Instead, the steps can be processed in reverse order or simultaneously. Furthermore, other operations can be added to these processes, or one or more steps can be removed from them.

[0020] Figure 1 This is a flowchart illustrating an exemplary method for preparing a liquid pool according to some embodiments of this specification. In some embodiments, process 100 may be executed automatically by a control system. For example, process 100 may be implemented by control commands, based on which the control system controls the components to complete various operations of process 100. In some embodiments, process 100 may be executed semi-automatically. For example, one or more operations of process 100 may be performed manually by an operator. In some embodiments, when completing process 100, one or more additional operations not described may be added, and / or one or more operations discussed herein may be removed. Additionally, Figure 1 The order of operations shown is not restrictive. Figure 1 As shown, process 100 may include the following steps.

[0021] In step 110, the first liquid is placed on the first sheet.

[0022] In some embodiments, the first sheet may include an electron microscope grid coated with an isolation film. For example, such as Figure 2 As shown, 210 represents the first layer, which is an electron microscope grid coated with an isolation film.

[0023] In some embodiments, the electron microscope screen may include various metal screens, such as copper screens, gold screens, nickel screens, molybdenum screens, etc., or any combination thereof.

[0024] In some embodiments, the isolation membrane may include a carbon film, a graphene film, or any combination thereof. On the one hand, coating with an isolation membrane can ensure that liquid does not overflow outside the first layer; on the other hand, coating with an isolation membrane can increase the thermal conductivity of the first layer, avoiding significant thermal effects under the electron beam of an electron microscope, thereby improving subsequent imaging results.

[0025] In some embodiments, the isolation film can be coated onto the electron microscope screen using a coating apparatus or the like, but this specification does not limit this process.

[0026] In some embodiments, the first layer may be coated with a microporous membrane. In some embodiments, the microporous membrane may include an aromatic membrane, a silicon oxide membrane, or any combination thereof. For example, such as Figure 3 As shown, 210 represents the first layer, and 211 represents the microporous membrane.

[0027] By coating the first layer with a microporous membrane, the first liquid can be embedded in the micropores, preventing liquid leakage during the assembly of the liquid pool. Furthermore, the microporous membrane can act as a buffer layer between the first liquid and the first layer (or the isolation membrane coated on the first layer), preventing the first liquid from crushing or excessively deforming the first layer (or the isolation membrane coated on the first layer) due to gravity or pressure, thus affecting subsequent assembly and imaging results.

[0028] Furthermore, in order to achieve good embedding and buffering effects, the micropore size of the microporous membrane also needs to be controlled within a suitable range. If it is too small, it will affect the embedding effect; if it is too large, it will not be able to play a good buffering role.

[0029] In some embodiments, the micropore size of the microporous membrane can be 50 nm-20 μm. In some embodiments, the micropore size of the microporous membrane can be 60 nm-18 μm. In some embodiments, the micropore size of the microporous membrane can be 65 nm-16 μm. In some embodiments, the micropore size of the microporous membrane can be 70 nm-15 μm. In some embodiments, the micropore size of the microporous membrane can be 80 nm-13 μm. In some embodiments, the micropore size of the microporous membrane can be 90 nm-11 μm. In some embodiments, the micropore size of the microporous membrane can be 100 nm-10 μm. In some embodiments, the micropore size of the microporous membrane can be 50 nm-10 μm. In some embodiments, the micropore size of the microporous membrane can be 60 nm-10 μm. In some embodiments, the micropore size of the microporous membrane can be 70 nm-10 μm. In some embodiments, the micropore size of the microporous membrane can be 80 nm-10 μm.

[0030] In some embodiments, a microporous membrane can be coated onto the first layer by methods such as magnetron sputtering or physical vapor deposition, but this specification does not limit this.

[0031] In some embodiments, the first liquid can be placed on the first sheet using a dropper, pipette, needle tip, capillary pipette, etc., but this specification does not limit this.

[0032] In step 120, an intermediate layer is applied over the first liquid.

[0033] In step 130, the second liquid is placed on the intermediate layer. For example, as... Figure 2 As shown, 205 represents the intermediate layer, which is used to separate the first liquid and the second liquid.

[0034] In some embodiments, similarly, the second liquid can be placed on the intermediate layer using a dropper, pipette, needle tip, capillary pipette, etc., and this specification does not limit this.

[0035] In some embodiments, the intermediate layer does not react with the first liquid and the second liquid.

[0036] In some embodiments, the intermediate layer may include an atomically-level two-dimensional material.

[0037] In some embodiments, the intermediate layer may include a MoS2 thin film.

[0038] In some embodiments, the thickness of the intermediate layer may be less than 5 nm. In some embodiments, the thickness of the intermediate layer may be less than 4 nm. In some embodiments, the thickness of the intermediate layer may be less than 3 nm. In some embodiments, the thickness of the intermediate layer may be less than 2 nm. In some embodiments, the thickness of the intermediate layer may be less than 1 nm.

[0039] By using an atomically-level two-dimensional material as an intermediate layer and limiting the thickness of the intermediate layer to a very small extent, it is possible to ensure that the electron beam of an electron microscope can penetrate it or break it due to electron beam irradiation, thereby allowing the first liquid and the second liquid to come into contact and react. This allows the reaction process of the two liquids to be observed in situ under an electron microscope.

[0040] In some embodiments, the intermediate layer may be any thin film that can be punctured by an electron beam or cracked by irradiation, and this specification does not limit this.

[0041] In some embodiments, the intermediate layer can be adhered by heat-release tape or polydimethylsiloxane (PDMS) and then released onto the first liquid by heating.

[0042] In some embodiments, the intermediate layer can be adhered to and then released onto the first liquid by controlling the speed at which the PDMS adheres to the intermediate layer (adhesion occurs when the speed is fast and release occurs when the speed is slow).

[0043] In some embodiments, the intermediate layer may be placed on the first liquid in any manner that enables film transfer, and this specification does not limit this.

[0044] In step 140, the second sheet is placed on the second liquid to form a liquid pool comprising the first liquid, the second liquid, the first sheet, the second sheet, and an intermediate layer.

[0045] In some embodiments, similar to the first layer, the second layer may include an electron microscope grid coated with an isolation membrane. In some embodiments, the second layer may also be coated with a microporous membrane. Further details regarding the first layer can be found in the description of the first layer and will not be repeated here.

[0046] It should be noted that the above description of process 100 is merely for illustration and explanation, and does not limit the scope of this application. Those skilled in the art can make various modifications and changes to process 100 under the guidance of this application. However, these modifications and changes are still within the scope of this application.

[0047] Example 1

[0048] An Ag nanowire suspension (first liquid) is placed on a transmission electron microscope copper mesh (first layer) coated with a carbon film and an aromatic film. A MoS2 film (which can be grown on a silicon wafer substrate) is then adhered to the Ag nanowire suspension using heat-release tape (which adheres at room temperature and detaches upon heating) and released onto the Ag nanowire suspension. A HAuCl4 solution (second liquid) is placed on the MoS2 film. The transmission electron microscope copper mesh (second layer) coated with a carbon film and an aromatic film is then placed on the HAuCl4 solution, thus forming a liquid pool that encapsulates the Ag nanowire suspension and the HAuCl4 solution and is separated by the MoS2 film.

[0049] By placing the liquid pool under a transmission electron microscope and irradiating it with an electron beam to break down or destroy the MoS2 film, the reaction process of the Ag nanowire suspension and HAuCl4 solution can be observed in situ, generating Au particles that adhere to the surface of the Ag nanowires.

[0050] Example 2

[0051] A Cu nanowire suspension (first liquid) is placed on a transmission electron microscope copper mesh (first layer) coated with a carbon film and an aromatic film. By controlling the adhesion speed of PMDS (i.e., adhesion occurs when the speed is fast and release occurs when the speed is slow), a MoS2 film (which can be grown on a silicon wafer substrate) is adhered and then released onto the Cu nanowire suspension. A HAuCl4 solution (second liquid) is placed on the MoS2 film. The transmission electron microscope copper mesh (second layer) coated with a carbon film and an aromatic film is placed on the HAuCl4 solution, thus forming a liquid pool that encapsulates the Cu nanowire suspension and the HAuCl4 solution and is separated by the MoS2 film.

[0052] By placing the liquid pool under a transmission electron microscope and irradiating it with an electron beam to break down or destroy the MoS2 film, the reaction process of the Cu nanowire suspension and HAuCl4 solution can be observed in situ, generating Au particles that adhere to the surface of the Cu nanowires.

[0053] The beneficial effects that the embodiments of this application may bring include, but are not limited to: (1) A liquid pool comprising the first liquid and the second liquid is formed by encapsulating and separating the first liquid and the second liquid through the first layer, the intermediate layer and the second layer. In a transmission electron microscope, the electron beam penetrates or breaks through the intermediate layer, and the first liquid and the second liquid react, and the reaction process can be observed in situ accordingly. (2) The first layer or the microporous membrane coated on the first layer can play a role in embedding and buffering. (3) The intermediate layer is an atomic-level two-dimensional material and its thickness is less than a preset thickness threshold, which can ensure that the electron beam can penetrate or break through the intermediate layer so that the first liquid and the second liquid react, thereby realizing the in-situ observation of the reaction process.

[0054] It should be noted that different embodiments may produce different beneficial effects. In different embodiments, the beneficial effects may be any one or a combination of the above, or any other possible beneficial effects.

[0055] The basic concepts have been described above. Obviously, for those skilled in the art, the detailed disclosure above is merely illustrative and does not constitute a limitation of this specification. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and corrections to this specification. Such modifications, improvements, and corrections are suggested in this specification and therefore remain within the spirit and scope of the exemplary embodiments described herein.

[0056] Furthermore, this specification uses specific terms to describe embodiments thereof. For example, "an embodiment," "one embodiment," and / or "some embodiments" refer to a particular feature, structure, or characteristic associated with at least one embodiment of this specification. Therefore, it should be emphasized and noted that references to "an embodiment," "one embodiment," or "an alternative embodiment" in different locations throughout this specification do not necessarily refer to the same embodiment. Moreover, certain features, structures, or characteristics in one or more embodiments of this specification can be appropriately combined.

[0057] Furthermore, unless expressly stated in the claims, the order of processing elements and sequences, the use of numbers and letters, or other names described in this specification are not intended to limit the order of the processes and methods described herein. Although various examples have been discussed in the foregoing disclosure of some embodiments of the invention that are currently considered useful, it should be understood that such details are for illustrative purposes only, and the appended claims are not limited to the disclosed embodiments; rather, the claims are intended to cover all modifications and equivalent combinations that conform to the spirit and scope of the embodiments described herein. For example, while the system components described above can be implemented using hardware devices, they can also be implemented solely using software solutions, such as installing the described system on existing servers or mobile devices.

[0058] Similarly, it should be noted that, in order to simplify the description disclosed herein and thus aid in the understanding of one or more embodiments of the invention, the foregoing description of embodiments in this specification may sometimes combine multiple features into a single embodiment, drawing, or description thereof. However, this method of disclosure does not imply that the subject matter of this specification requires more features than those mentioned in the claims. In fact, the embodiments contain fewer features than all the features of a single embodiment disclosed above.

[0059] In some embodiments, numbers describing the quantity of components and attributes are used. It should be understood that such numbers used in the description of embodiments are modified in some examples with the terms "approximately," "approximately," or "generally." Unless otherwise stated, "approximately," "approximately," or "generally" indicates that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximate values, which may be changed depending on the characteristics required by individual embodiments. In some embodiments, numerical parameters should take into account specified significant digits and employ a general method of digit reservation. Although the numerical ranges and parameters used to confirm their breadth of range in some embodiments of this specification are approximate values, in specific embodiments, such values ​​are set as precisely as feasible.

[0060] For each patent, patent application, patent application publication, and other material such as articles, books, specifications, publications, and documents referenced in this specification, the entire contents of which are incorporated herein by reference. This excludes historical application documents that are inconsistent with or conflict with the content of this specification, as well as documents that limit the broadest scope of the claims in this specification (currently or subsequently appended to this specification). It should be noted that in the event of any inconsistency or conflict between the descriptions, definitions, and / or terminology used in the supplementary materials to this specification and the content of this specification, the descriptions, definitions, and / or terminology used in this specification shall prevail.

[0061] Finally, it should be understood that the embodiments described in this specification are merely illustrative of the principles of the embodiments described herein. Other variations may also fall within the scope of this specification. Therefore, alternative configurations of the embodiments described herein are intended to be illustrative rather than limiting, and should be considered consistent with the teachings of this specification. Accordingly, the embodiments described herein are not limited to those explicitly introduced and described herein.

Claims

1. A method for preparing a liquid cell in an electron microscope, characterized in that, The method includes: Place the first liquid onto the first sheet; Cover the first liquid with an intermediate layer; A second liquid is placed on the intermediate layer, the intermediate layer serving to separate the first liquid and the second liquid; The second sheet is placed on the second liquid to form a liquid pool comprising the first liquid, the second liquid, the first sheet, the second sheet, and the intermediate layer.

2. The method as described in claim 1, characterized in that, The first and second sheets include electron microscope grids coated with an isolation membrane.

3. The method as described in claim 1, characterized in that, The first and second sheets are coated with microporous membranes.

4. The method as described in claim 3, characterized in that, The micropore size of the microporous membrane is 100nm-10μm.

5. The method as described in claim 1, characterized in that, The intermediate layer does not react with the first liquid and the second liquid.

6. The method as described in claim 1, characterized in that, The intermediate layer comprises atomically two-dimensional materials.

7. The method as described in claim 1, characterized in that, The intermediate layer comprises a MoS2 thin film.

8. The method as described in claim 1, characterized in that, The thickness of the intermediate layer is less than 2 nm.

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