A method for the controllable preparation and patterning of two-dimensional transition metal dichalcogenide layers based on surface plasmon waves

Abstract

The present invention provides a method for the controllable preparation and patterning of two-dimensional transition metal dichalcogenide layers based on surface plasmon waves, comprising the following steps: using a laser with a wavelength of 670 nm to irradiate the The surface of the sample placed in an aqueous solution; the output power of the laser that excites the surface plasmon wave is adjusted to obtain a transition metal disulfide with a controllable number of layers; the number of layers is 1 layer, 2 layers or 3 layers; the surface plasmon wave is adjusted The propagation direction and etching time of the patterned layered transition metal dichalcogenides are obtained. Taking molybdenum disulfide as a representative example, the layer number control of molybdenum disulfide is realized by adjusting the output power of the light source that excites surface plasmon waves. The simultaneous etching process depends on the propagating direction of the surface plasmon waves, enabling the patterning of various MoS2 homostructures. The invention is easy to operate, has very little pollution and damage to the sample, and the surface of the sample after treatment is complete and clean.

Description

technical field [0001] The invention belongs to the technical field of preparation of two-dimensional nanomaterials, and in particular relates to a preparation method for the controllable preparation and patterning of two-dimensional transition metal dichalcogenide layers based on surface plasma waves. Background technique [0002] Two-dimensional transition metal dichalcogenide materials have become a hotspot in basic scientific research due to their wonderful layer-dependent properties, especially in the fields of optoelectronics, spintronics, and recently, valleytronics. The reduction of the number of layers of 2D transition metal dichalcogenides to the atomic layer induces significant changes in the electronic structure and crystal symmetry, which in turn affects their optical, electrical, and magnetic properties. For example, due to the bandgap change and interband optical selection from bulk to monolayer, in monolayer MX 2 Strong photoluminescence and valley polarizat...

AI Technical Summary

Problems solved by technology

Overall, the products obtained by mechanical exfoliation and solution exfoliation showed random layer distributions, which prevented the controllable preparation of transition metal dichalcogenide nanosheets with the desired number of layers from bulk materials.

The subsequent complex screening procedures and characterization methods are not only time-consuming, but also destroy and degrade the nanosheets, making it impossible to ensure the exact number of layers

In addition, the small lateral size of transition metal dichalcogenide nanosheets prepared by the exfoliation method does not always guarantee the needs of large-scale devices.

Although the chemical vapor deposition method is a common method for preparing two-dimensional transition metal dichalcogenide materials, it is still difficult to control the number of layers of the transition metal dichalcogenide material and the polycrystalline layer caused by the grain boundary.

[0004] Therefore, the controllable preparation of 2D transition metal dichalcogenide materials with tunable layers and large area remains a great challenge.

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