阅读说明：本技术 一种用于透射电镜表征的液体样品腔及其制备方法 (Liquid sample cavity for transmission electron microscope characterization and preparation method thereof ) 是由 贺龙兵 杨宇峰 宗思洁 于 2019-09-17 设计创作，主要内容包括：本发明公开了一种用于透射电镜表征的液体样品腔及其制备方法,包括以下步骤：1)取两个透射电镜表征用低熔点金属载网骨架,分别在其一个表面覆盖上有机薄膜得金属载网；2)将一个金属载网以有机薄膜在下方的方式放置,从金属载网的上方滴加待表征的液体样品,之后在其表面以有机薄膜在上方的方式覆盖另一个金属载网；3)对两个金属载网加热至载网骨架开始软化,外力挤压至载网骨架相互融合,在两个金属载网的交叉网格中形成密封液体样品窗口；4)待两个金属载网降至室温,载网骨架硬化后进行检漏,得到具有多个样品窗的液体样品腔。该方法以低熔点金属载网为基础,制备简易、成本低廉、重复性高、使用简单,可用于透射电镜对液体环境表征。(The invention discloses a liquid sample cavity for transmission electron microscope characterization and a preparation method thereof, wherein the liquid sample cavity comprises the following steps: 1) taking two low-melting-point metal mesh carrying frameworks for transmission electron microscope characterization, and covering an organic film on one surface of each framework to obtain a metal mesh carrying frame; 2) placing one metal carrying net in a mode that the organic film is arranged below, dripping a liquid sample to be characterized from the upper part of the metal carrying net, and then covering the other metal carrying net on the surface of the metal carrying net in a mode that the organic film is arranged above; 3) heating the two metal carrying nets until the carrying net frameworks begin to soften, extruding by external force until the carrying net frameworks are mutually fused, and forming a sealed liquid sample window in the crossed grids of the two metal carrying nets; 4) and (3) after the two metal carrying nets are cooled to room temperature, carrying out leak detection after the carrying net framework is hardened, and obtaining the liquid sample cavity with a plurality of sample windows. The method is based on the low-melting-point metal grid, is simple and easy to prepare, low in cost, high in repeatability and simple to use, and can be used for characterization of a transmission electron microscope on a liquid environment.)

1. A preparation method of a liquid sample cavity for transmission electron microscope characterization is characterized by comprising the following steps: the method comprises the following steps:

1) taking two transmission electron microscope characterization low-melting-point metal mesh-carrying frameworks, and covering an organic film on one surface of each low-melting-point metal mesh-carrying framework to obtain a metal mesh;

2) placing one of the metal carrying nets with the organic film below, dripping a liquid sample to be characterized from the upper part of the metal carrying net, and then covering the other metal carrying net on the surface of the metal carrying net with the organic film above;

3) heating the two metal carrying nets covered together until the low-melting-point metal carrying net frameworks of the metal carrying nets begin to soften, extruding by external force until the low-melting-point metal carrying net frameworks are fused with each other, and forming a plurality of sealed liquid sample windows in the crossed grids of the two metal carrying nets;

4) and (3) after the two metal carrying nets are cooled to room temperature and the low-melting-point metal carrying net framework is hardened, carrying out leak detection to obtain a liquid sample cavity which is not leaked, provided with a plurality of sealed liquid sample windows and used for transmission electron microscope characterization.

2. The method for preparing a liquid sample cavity for transmission electron microscope characterization according to claim 1, wherein the method comprises the following steps: the low-melting-point metal is a lead-tin alloy, a lead-tin-indium alloy or a bismuth-tin alloy, and the melting point of the low-melting-point metal is 50-100 ℃.

3. The method for preparing a liquid sample cavity for transmission electron microscope characterization according to claim 1, wherein the method comprises the following steps: the mesh number of the low-melting-point metal mesh-carrying framework is 200-1000 meshes, meshes in the metal mesh-carrying framework are round holes, square holes or hexagonal holes, and the thickness of the framework is 10-20 mu m.

4. The method for preparing a liquid sample cavity for transmission electron microscope characterization according to claim 1, wherein the method comprises the following steps: the organic film is a diamond film or a collodion film, and the thickness of the organic film is 10-30 nm.

5. The method for preparing a liquid sample cavity for transmission electron microscope characterization according to claim 1, wherein the method comprises the following steps: the step 3) of heating the two metal nets covered together means heating by using a heating table.

6. The method for preparing a liquid sample cavity for transmission electron microscope characterization according to claim 1, wherein the method comprises the following steps: the thickness of the liquid in the sealed liquid sample window in the step 3) is 0.5-20 μm.

7. A liquid sample cavity prepared by the method according to any one of claims 1 to 6 and used for transmission electron microscopy characterization, wherein the liquid sample cavity is characterized in that: the liquid sample cavity is formed by vertically placing two low-melting-point metal mesh-carrying frameworks for transmission electron microscope characterization and crosswise fusing the mesh-carrying frameworks, and the upper surface of the low-melting-point metal mesh-carrying framework for transmission electron microscope characterization positioned above and the lower surface of the low-melting-point metal mesh-carrying framework for transmission electron microscope characterization positioned below are covered with organic thin films.

8. A liquid sample chamber for transmission electron microscopy characterization according to claim 7 wherein: in the low-melting-point metal grid-carrying framework for the transmission electron mirror characterization, the thickness of the framework is 0.5-20 mu m, meshes in the metal grid-carrying framework are round holes, square holes or hexagonal holes, and the low-melting-point metal is lead-tin alloy, lead-tin-indium alloy or bismuth-tin alloy; the organic film is a diamond film or a collodion film, and the thickness is 10-30 nm; the thickness of the liquid in the liquid sample cavity is 0.5-20 μm.

The technical field is as follows:

the invention relates to a liquid sample cavity for transmission electron microscope characterization and a preparation method thereof, and belongs to the field of transmission electron microscope characterization and testing.

Background art:

in recent years, nanomaterials have been widely used in the industries of medical devices, electronic devices, coatings, and the like. As the nano material has unique properties, the representation of the microstructure and the physicochemical properties of the nano material becomes an important basis for promoting the development of functional devices. Thanks to the ultra-high resolution, the transmission electron microscope is one of the most important technical methods for testing and characterizing the morphology, structure, components and physical properties of the nano-materials.

Because the liquid sample has a large saturated vapor pressure and cannot stably exist in a high vacuum environment of the transmission electron microscope, the traditional transmission electron microscope is only suitable for representing thin solid samples. With the continuous development of experimental instruments, the transmission electron microscope technology in the in-situ liquid environment is mature day by day, and a new opportunity is provided for the research on the aspects of nucleation, growth, self-assembly, structural characterization of biological samples and the like of nano materials in the liquid environment.

At present, the liquid sample cavity of the transmission electron microscope mainly uses the sample cavity combining the ultrathin silicon nitride window and the silicon-based substrate, and the liquid sample cavity with high resolution ratio in the market is relatively high in cost due to the large difficulty in manufacturing the window. In addition, the observation window size of the commercial liquid sample cavity in the market is small, and a single liquid cavity chip usually has only a few observation windows, which is not beneficial to large-scale search and large-sample-number statistical analysis of specific samples in a liquid environment, so that the design of the liquid sample cavity with low cost, multiple observation windows and simple preparation, use and operation has great practical value.

The invention content is as follows:

the technical problem is as follows: the invention aims to provide a liquid sample cavity for transmission electron microscope characterization and a preparation method thereof, provides a low-cost solution for characterizing nucleation, growth, self-assembly and the like of a nano material in a liquid environment, solves the problems of complex process, high technical level requirement and the like in the production of the liquid sample cavity in the market, and solves the problems of small size of an observation window, small number of the observation windows and the like of a mainstream liquid sample cavity product.

The technical scheme is as follows: in order to achieve the above object, the present invention provides a method for preparing a liquid sample chamber for transmission electron microscope characterization, the method comprising the following steps:

1) taking two transmission electron microscope characterization low-melting-point metal mesh-carrying frameworks, and covering an organic film on one surface of each low-melting-point metal mesh-carrying framework to obtain a metal mesh;

2) placing one of the metal carrying nets with the organic film below, dripping a liquid sample to be characterized from the upper part of the metal carrying net, and then covering the other metal carrying net on the surface of the metal carrying net with the organic film above;

3) heating the two metal carrying nets covered together until the low-melting-point metal carrying net frameworks of the metal carrying nets begin to soften, extruding by external force until the low-melting-point metal carrying net frameworks are fused with each other, and forming a plurality of sealed liquid sample windows in the crossed grids of the two metal carrying nets;

4) and (3) after the two metal carrying nets are cooled to room temperature and the low-melting-point metal carrying net framework is hardened, carrying out leak detection to obtain a liquid sample cavity which is not leaked, provided with a plurality of sealed liquid sample windows and used for transmission electron microscope characterization.

Wherein:

the low-melting-point metal is a lead-tin alloy, a lead-tin-indium alloy or a bismuth-tin alloy, and the melting point of the low-melting-point metal is 50-100 ℃.

The transmission electron mirror is characterized in that the shape of the low-melting-point metal mesh-carrying framework is a circle with the diameter of 3 mm.

The mesh number of the low-melting-point metal mesh-carrying framework is 200-1000 meshes, meshes in the metal mesh-carrying framework are round holes, square holes or hexagonal holes, and the thickness of the framework is 10-20 mu m.

The organic film is a diamond film or a collodion film, and the thickness of the organic film is 10-30 nm.

The step 3) of heating the two metal nets covered together means heating by using a heating table.

And 3) extruding the low-melting-point metal frameworks by external force until the low-melting-point metal frameworks are fused with each other, wherein the external force is applied in a direction vertical to the metal mesh.

The thickness of the liquid in the sealed liquid sample window in the step 3) is 0.5-20 μm.

The invention also provides a liquid sample cavity for transmission electron microscope characterization, which is prepared by the method, the liquid sample cavity is formed by vertically placing two low-melting-point metal mesh carrying frameworks for transmission electron microscope characterization and crosswise fusing the mesh carrying frameworks, and the upper surface of the upper low-melting-point metal mesh carrying framework for transmission electron microscope characterization and the lower surface of the lower low-melting-point metal mesh carrying framework for transmission electron microscope characterization are covered with organic films.

Wherein:

in the low-melting-point metal mesh-carrying framework for the transmission electron mirror characterization, the thickness of the framework is 0.5-20 mu m, the metal mesh-carrying framework is circular with the diameter of 3mm, meshes in the metal mesh-carrying framework are round holes, square holes or hexagonal holes, and the low-melting-point metal is lead-tin alloy, lead-tin-indium alloy or bismuth-tin alloy; the organic film is a diamond film or a collodion film, and the thickness is 10-30 nm; the thickness of the liquid in the liquid sample cavity is 0.5-20 μm.

Has the advantages that: compared with the prior art, the invention has the following advantages:

the liquid sample cavity for transmission electron microscope characterization provided by the invention has the advantages that the number of windows is large, the size of the window is large and the like, which cannot be met by the current market, so that the problems of high price, small observation window and the like of the liquid sample cavity in the market are solved, a more flexible method is provided for various researches on nucleation, growth, self-assembly and the like of nano materials in a transmission electron microscope liquid environment, and the liquid sample cavity is low in cost, high in repeatability and simple to use.

The preparation method of the liquid sample cavity for the transmission electron microscope characterization, provided by the invention, has the advantages of relatively low material cost, low technical level, low requirements on the manufacturing environment and equipment, and capability of being operated in a laboratory, so that the preparation method has the advantages of simplicity and easiness in manufacturing, low cost, convenience in use, short time consumption and the like.

Drawings

FIG. 1 is a flow chart of a method for preparing a liquid sample chamber for transmission electron microscope characterization according to the present invention;

fig. 2 is a picture of a liquid sample chamber for transmission electron microscope characterization provided in the present invention, where a is a scanning electron microscope image of the liquid sample chamber, and b is a scanning electron microscope image of the internal structure of the liquid sample chamber.

Detailed Description

The invention provides a liquid sample cavity for transmission electron microscope characterization and a preparation method thereof, the method is based on a low-melting-point metal carrier net, the prepared liquid sample cavity is low in cost, high in repeatability and simple to use, and the preparation method is simple and easy to prepare and can be used for carrying out characterization on various aspects such as nucleation, growth and self-assembly of a nano material under a liquid environment by a transmission electron microscope. The following is a more detailed description taken in conjunction with the accompanying drawings.