Method for detecting two dimensional nanostructured material film surface detect

Abstract

The invention discloses a detection method of two dimensional nanostructured material film surface detect distribution and relates to the field of material surface defect and its distribution detection. The method comprises the following steps of: firstly drying a sample beforehand, removing water molecules on the surface of the sample, allowing a gas mixture of steam and other gases to flow on the surface of the sample by a steam injection device, carrying out condensation operation, acquiring morphological, distribution and quantitative features of droplets on the surface of the film material under single and multiple condensation conditions, and determining distribution law of the sample surface defect. As the absorption and condensation process of the water molecules on the surface ofthe two dimensional film material is usually completed in milliseconds, the defect detection is very rapid; in addition, deionized water vapor which is mild is used on the surface of the material, and the sample can be restored to the original state just by a subsequent drying step. Therefore, the method is lossless for the sample to be detected.

Description

technical field [0001] The invention relates to the field of detection of material surface defects and their distribution, in particular to a detection method for the distribution of defects on the surface of two-dimensional nanostructure materials. Background technique [0002] Two-dimensional materials are usually in the shape of a thin film, assuming that the dimensions of the film in the three-dimensional direction are L x , L y and L z , if the size of a certain two directions (for example: L x , L y ) are greater than the Fermi wavelength of the material (λ F ), while the scale in a certain direction (for example: L z ) is less than or equivalent to its Fermi wavelength (λ F ), then this material is a two-dimensional material. The thickness of two-dimensional material films can be below 100 nanometers, and the thinnest can be at the thickness of a single atom. The common one is a layered crystal structure. Since the lattice has dense interatomic forces in the h...

AI Technical Summary

Problems solved by technology

Defects on the surface of two-dimensional material films have a significant impact on its physical or chemical properties, and can even significantly change some properties. For example, ideal graphene should be hydrophobic, but surface defects can cause graphene to have a strong resistance to water. Adsorption, so that the graphene containing defects is weakly hydrophobic or even hydrophilic

Among them, although the Raman spectrometer can detect the existence of defects more sensitively, it is a statistical result that cannot accurately determine the location and distribution of defects.

However, STM and AFM determine defects by characterizing the surface topography of materials, which can characterize precise point defects and their positions, but the scanning range of the probe is limited (within hundreds of microns), and due to the scanning of the probe, the speed is relatively slow , the cycle is longer, in addition, STM requires an ultra-high vacuum environment, the working conditions are harsh, and the operation process is complicated

Optical microscopy can detect partial defects quickly and in a large area, but the premise is that the defects must have optical contrast, such as macroscopic wrinkles, or the boundaries of atomic thickness can be resolved with the help of other contrast materials, but limited to the resolution of optical microscopy (micrometer scale), it is difficult to detect atomic scale steps, lattice defects or boundaries with pure optical microscopy

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