Comprehensive Characterisation of Hydrothermally Grown Two-Dimensional Tellurium Using Microscopy Techniques

Abstract

Tellurium, an elemental solid crystal, is a narrow band-gap semiconductor that has a band-gap of approximately 0.35 eV at room temperature. The structure belongs to the trigonal lattice class and exhibits inherent structural anisotropy. Structural stud ies of bulk tellurium are particularly interesting because it lacks inversion symmetry and exhibits chirality. Two-dimensional tellurium shows strong potential for a wide range of device ap plications, including photodetectors, field-effect transistors, piezoelectric devices, and others. The environmental stability of two-dimensional tellurium flakes is promising. This particular factor alone makes tellurium an excellent candidate for industry and academic-based applications. Additionally, the presence of spin–orbit coupling (SOC) allows for the possibility of devices that utilize not only the charge of electrons but also their spin, making this a promising direction for future technologies. The thesis investigates the surface and structural properties of two-dimensional Tellurium flakes synthesised via hydrothermal synthesis. A comprehensive character isation was performed using Field Emission Scanning Tunnelling Microscopy, high resolution Transmission Electron Microscopy, Atomic force Microscopy, Raman Spec troscopy and Scanning Tunnelling Microscopy. The result reveals surface morphology, layer thickness, and crystallinityTellurium, an elemental solid crystal, is a narrow band-gap semiconductor that has a band-gap of approximately 0.35 eV at room temperature. The structure belongs to the trigonal lattice class and exhibits inherent structural anisotropy. Structural stud ies of bulk tellurium are particularly interesting because it lacks inversion symmetry and exhibits chirality. Two-dimensional tellurium shows strong potential for a wide range of device ap plications, including photodetectors, field-effect transistors, piezoelectric devices, and others. The environmental stability of two-dimensional tellurium flakes is promising. This particular factor alone makes tellurium an excellent candidate for industry and academic-based applications. Additionally, the presence of spin–orbit coupling (SOC) allows for the possibility of devices that utilize not only the charge of electrons but also their spin, making this a promising direction for future technologies. The thesis investigates the surface and structural properties of two-dimensional Tellurium flakes synthesised via hydrothermal synthesis. A comprehensive character isation was performed using Field Emission Scanning Tunnelling Microscopy, high resolution Transmission Electron Microscopy, Atomic force Microscopy, Raman Spec troscopy and Scanning Tunnelling Microscopy. The result reveals surface morphology, layer thickness, and crystallinity