Ambipolar Field Effect in Sb-Doped Bi2Se3 Nanoplates by Solvothermal Synthesis

A topological insulator is a new phase of quantum matter with a bulk band gap and spin-polarized surface states, which might find use in applications ranging from electronics to energy conversion. Despite much exciting progress in the field, high-yield solution synthesis has not been widely used for the study of topological insulator behavior. Here, we demonstrate that solvothermally synthesized Bi2Se3 nanoplates are attractive for topological insulator studies. The carrier concentration of these Bi2Se3 nanoplates is controlled by compensational Sb doping during the synthesis. In low-carrier-density, Sb-doped Bi2Se3 nanoplates, we observe pronounced ambipolar field effect that demonstrates the flexible manipulation of carrier type and concentration for these nanostructures. Solvothermal synthesis offers an affordable, facile approach to produce high-quality nanomaterials to explore the properties of topological insulators.