Morphological evolution of self-deposition Bi2Se3 nanosheets by oxygen plasma treatment

Abstract

Bi2Se3 nanosheets were successfully synthesized by a microwave-assisted approach in the presence of polyvinylpyrroli done at a temperature of 180 °C for 2 h. The thin film was prepared on a silicon wafer via a self-deposition process in a Bi2Se3 nanosheet ink solution using the evaporation-induced self-assembly method. The structure and morphology of the obtained products were characterized by X-ray diffraction, scanning electron microscopy (SEM), x-ray photoelectron spectroscopy, and Raman spectroscopy. The highly uniform Bi2Se3 particles could be formed by controlling the oxygen plasma treatment time. After the plasma pretreatment from 10 to 20 s, the surface of Bi2Se3 film evolved from the worm-like structure to particles. The highly uniform thin film was formed on further increasing the plasma treatment time, which is consistent with the observed SEM results. Several important processes can result in the morphological evolution of Bi2Se3 nanosheets: (1) formation of Bi2Se3 oxide layer; (2) self-assembly of oxide nanoparticles under the action of high-energy oxygen plasma; and (3) electrostatic interaction and etching mechanism.

Copper migration and surface oxidation of CuxBi2Se3 in ambient pressure environments

“…There are other factors that are not present in this model which can also affect the evolution of Cu x Bi 2 Se 3 surface chemistry. These include imperfect cleaves that can form step edge sites for oxidation [34], lingering Cu remaining at the surface after the cleave, different Bi, Se surface terminations [42], as well as nanosheet morphology [44,54]. Other Cu, Se compositional distributions are possible and consistent with our experimental observations, such as ones with discontinuous step edges or sigmoidal distributions.…”

Materials analysis and focused ion beam nanofabrication of topological insulator Bi2Se3

“…Directly growing nanotstructures bottom-up into the necessary geometries and defect densities would be ideal, but controlled growth and scaling of such devices is complicated. An alternative is to use top-down methods, such as ion milling, to modify the Bi 2 Se 3 [16][17][18][19][20][21][22][23][24][25] .…”

In-situ synthesized and pattern Ag/Bi2Se3 composite structure by LDW and photothermal conversion

“…As-prepared Bi 2 Se 3 powder is dispersed in 50 ml alcohol. A uniform Bi 2 Se 3 thin film can be prepared on the glass substrate by evaporating self-assembling process 45 . The intrinsic glass substrate has been carefully cleaned in a sonicating bath warm acetone (50 °C) for an hour to remove the organic pollutant.…”