COLLOIDAL PRODUCTION OF ULTRATHIN 2D-Bi₂Se₃ TOPOLOGICAL INSULATOR AND ITS DOPED ANOLOGUES

2D Bi₂Se₃ nanostructures with few quintuple layers (QLs) thickness have emerged new exciting material due its topological insulator properties. The surface conductivity of these exotic materials is highly influenced by their layer thickness. In contrast to traditional MBE, CVD techniques, these structures can be alternatively produced in solution phase with controlled and uniform thickness (~5 -10 QL) that is small compared to their lateral dimensions. Moreover, incorporating dopants like Mn²⁺,Cu^+/2+ and Sb³⁺ into these topological insulators can alter their chemical potential which also provides us additional degree of freedom which can be used to tune their properties by varying their composition. These doped-Bi₂Se₃ nanostructures have possibilities to open new door for device engineering in the field of spintronics and low-energy electronics.

Here, we will present the colloidal synthesis of the ultrathin 2D Bi₂Se₃ nanosheetsalong with their physiochemical properties. We will show the effect of magnetic and non-magnetic doping on the shape, size, optical and magnetic properties of these 2D nanostructures. Structural, compositional and optical characterizations are going to be presented using SEM, TEM, UV-visible absorption, powder X-diffraction (PXRD), XPS and SQUID measurements.