title: Exfoliation of Layered Topological Insulators Bi2Se3and Bi2Te3via Electrochemistry.
abstract: Among layered materials, topological insulators such as Bi2Se3and Bi2Te3are lately attracting much attention due to particular electronic properties and, especially with Bi2Te3, excellent thermoelectric properties. Methods of preparation of few-layered nanosheets of Bi2Se3and Bi2Te3range from the bottom-up chemical vapor deposition or hydrothermal synthesis from oxide precursors to the top-down mechanical exfoliation and liquid-based exfoliation supported by sonication from the natural bulk crystals. Here, we propose a simple and rapid electrochemical approach to exfoliate natural Bi2Se3and Bi2Te3crystals in aqueous media to single/few-layer sheets. The exfoliated materials have been characterized by scanning transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray powder diffraction, high-resolution transmission electron microscopy, and Raman spectroscopy in addition to evaluation of their electrochemical properties. This electrochemical procedure represents a simple, reagent-free, and scalable method for the fabrication of single/few-layer sheets of these materials.
authors.affiliation: Division of Chemistry & Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371.
authors.forename: Adriano
authors.initials: A
authors.lastname: Ambrosi
authors.affiliation: Department of Inorganic Chemistry, University of Chemistry and Technology Prague , Technická 5, 166 28 Prague 6, Czech Republic.
authors.forename: Zdeněk
authors.initials: Z
authors.lastname: Sofer
authors.affiliation: Department of Inorganic Chemistry, University of Chemistry and Technology Prague , Technická 5, 166 28 Prague 6, Czech Republic.
authors.forename: Jan
authors.initials: J
authors.lastname: Luxa
authors.affiliation: Division of Chemistry & Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371.
authors.forename: Martin
authors.identifier: 0000-0001-5846-2951
authors.initials: M
authors.lastname: Pumera
keywords: electrochemistry; exfoliation; hydrogen evolution reaction; layered compound; topological insulator