Quick detection method of two-dimensional nano-material anisotropy

Abstract

The invention provides a quick detection method of two-dimensional nano-material anisotropy. The method comprises the following steps: preparing a two-dimensional nano-material sample; fixing the prepared two-dimensional nano-material sample on a stage of an optical microscope; humidifying a surface of the two-dimensional nano-material sample; performing image collection on the surface of the two-dimensional nano-material sample by utilizing the optical microscope to acquire a distribution condition of liquid drops on the surface of the two-dimensional nano-material sample; and determining theanisotropy of the two-dimensional nano-material sample according to the distribution condition of liquid drops on the surface of the two-dimensional nano-material sample. The experimental equipment required by the detection method is simple, and the operation is convenient and quick; a zigzag direction and an armchair direction of the two-dimensional nano-sheet can be detected just needing a fewseconds; furthermore, the detection method is high in accuracy rate, free from damaging the two-dimensional nano-sheet sample, and extensive in application prospect.

Description

technical field [0001] The invention relates to the technical field of chemical testing, in particular to a rapid detection method for the anisotropy of two-dimensional nanomaterials. Background technique [0002] As a new type of two-dimensional semiconductor material, two-dimensional black phosphorus has attracted extensive attention of researchers. In particular, compared with other materials with high symmetry, black phosphorus has a unique in-plane anisotropy, which originates from the asymmetry of its crystal structure, that is, along two directions perpendicular to each other in the plane of black phosphorus: Armchair direction and zigzag direction, its crystal structure presents folding shape and ridge shape respectively, resulting in different bond lengths and bond angles of covalent bonds between atoms along these two directions, making black phosphorus physical, chemical, The mechanical and thermal properties show significant differences along different crystal o...

AI Technical Summary

Problems solved by technology

[0003] The existing detection methods for the anisotropy of two-dimensional black phosphorus are mainly analyzed indirectly through its characterization in optics, electronics, thermal, and mechanics. For example, in terms of optics, the anisotropy of black phosphorus is reflected in the Optical absorption spectrum, extinction spectrum, transmission spectrum, reflection spectrum, photoluminescence spectrum and photocurrent spectrum, etc.; in electronics, the effective mass of electrons and holes of black phosphorus presents obvious anisotropy. In terms of heat, the anisotropic thermal conductivity of black phosphorus mainly comes from the anisotropic phonon distribution, which can be measured by micro-area Raman In terms of mechanics, the anisotropy of black phosphorus is mainly reflected in the difference in its Young's modulus and resonance frequency along different directions, which can be analyzed by means of atomic force microscopy and mechanical testing; and A more intuitive detection method is Raman spectroscopy detection, the characteristic peak of Raman vibration has a certain anisotropy, and the in-plane B 2g and A g 2 The zigzag (zigzag) direction has a larger peak, while A g 1 The peak intensity of the armchair (armchair) direction is greater, but it requires a very complicated data processing and analysis process, and will cause damage to the two-dimensional black phosphorus nanosheets

[0004] In summary, the existing detection methods for the anisotropy of two-dimensional nanomaterials not only require very sophisticated and expensive detection and testing equipment, as well as complex data processing and analysis, but also cause a certain degree of damage to the two-dimensional nanosheets.

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