Method for preparing black phosphorus nanosheets

Abstract

The invention discloses a method for preparing black phosphorus nanosheets. The method comprises the following steps: (1) assembling black phosphorus used as an electrode and an organic solvent containing an intercalating agent, used as an electrolyte, in order to form an H-shaped electrolytic cell; (2) applying a current or voltage between the electrodes to intercalate and expand the black phosphorus; (3) filtering and washing the treated black phosphorus obtained in step (2), and carrying out ultrasonic vibration treatment on the treated black phosphorus in an organic solvent; and (4) centrifuging the obtained solution, and collecting the obtained supernatant to obtain a uniform-size black phosphorus nanosheet dispersion. The black phosphorus nanosheets stripped by the method have a thickness of 2-100 nm and a lateral dimension of 10 nm to 50 [mu]m. The method solves the problem of difficult control of the thickness and the lateral dimension of the black phosphorus nanosheets duringthe preparation of the black phosphorus nanosheets in the prior art, also solves the problem of too long time in traditional black phosphorus nanosheet preparation methods, and has the advantages of simple preparation process, low energy consumption, low cost, and realization of large-scale production.

Description

technical field [0001] The invention belongs to the preparation technology of inorganic nanometer materials, in particular to a method for preparing black phosphorus nanosheets. Background technique [0002] Black phosphorus is a crystal with metallic luster, which is black and has a flaky structure, especially black phosphorus with a wrinkled layered structure is the most attractive one among the allotropes of elemental phosphorus. Due to its excellent semiconductor properties, black phosphorus has become one of the most potential two-dimensional semiconductors after graphene and transition metal chalcogenides. Black phosphorus has a tunable direct band gap, and when the number and size of layers are appropriate, it has a high carrier mobility (up to 6.5×10 4 cm 2 / V.s), extremely large switching ratio characteristics (10 4 ~10 5 ) and obvious anisotropy; in addition, it also has good thermal conductivity, thermoelectric properties, photovoltaic effect, polarized light ...

AI Technical Summary

Problems solved by technology

The process is difficult to control, the yield is low, and the size and size of the phosphorene obtained are not uniform. If phosphorene of a certain size needs to be used, further screening is required.

Although CN104779380A shows that its method can be customized in size and thickness, it can be seen from the numerical values ​​of its examples that the size and thickness of phosphorene prepared are a range value, so this expression is controversial, because the method adopts a simple The one-step constant current and constant voltage method is used for stripping, so it is difficult to achieve the effect of controlling the thickness and size, and the device does not isolate the two electrodes, and the other level of product is likely to affect or pollute the stripped black phosphorus electrode, affecting the black phosphorus obtained. Purity of slices

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