Surface Defines the Properties: Colloidal Bi2Se3 Nanosheets with High Electrical Conductivity
Year: 2021
Type: article
Abstract: We investigated the colloidal synthesis of Bi 2 Se 3 nanosheets in ethylene glycol with the goal of increasing their lateral dimensions while keeping their thickness within a few nanometers. The influence of proton-donating sulfuric acid was found to be a triggering factor that promoted the lateral growth of up to 10 μm, whereas the thickness remained in the range 10–12 nm. The lateral size distribution was further optimized by size-selective precipitation enabling individual contacting of the nanosheets by electron-beam lithography. Electrical characterization of individually contacted nanosheets revealed a metal-like temperature dependence of the resistivity and values of the specific conductivity in the range of 470 S/cm at room temperature and 880 S/cm at 5.5 K, which is attributed to the surface-induced off-stoichiometry. The presented colloidal nanosheets can potentially serve as a platform for further studies on topologically nontrivial surface states and arising quantum phenomena in two-dimensional systems.
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W3138913835