TY - THES

T1 - Mechanical and electronic properties of monolayer TMDCs

T2 - A DFT study

AU - Ziegler, Maximilian

N1 - no embargo

PY - 2024

Y1 - 2024

N2 - In recent years, materials research in electronics has been tied to the trend of downsizing, where the focus lies on creating smaller and smaller structures that can be integrated into electronic devices. With the advent of graphene, a two-dimensional carbon structure, new atomically thin materials have become a reality, some of which exhibit desired chemical and structural stability alongside sought-after electronic and optical properties. Among these, transition metal dichalcogenides (TMDCs), have attracted interest of the scientific community. These materials possess the chemical formula MX2, where “M” denotes any transition metal of the periodic table and “X2” represents two covalently bonded chalcogen atoms. These include Sulfur (S), Selenium (Se), Tellurium (Te), and also a combination of these.Simulation studies of the exotic properties of TMDCs have accumulated, sometimes surpass- ing experimental evidence. However, a comprehensive overview that presents the different types and fundamental properties of these materials in a clear and straightforward manner is missing. The first objective of this thesis is to close this gap, with the primary interest lying in providing an overview of the basic elastic and electronic properties of these emerg- ing materials as a function of their structure and composition. Its second objective is to investigate the effects of straining and shearing on TMDC structures, mainly to investigate the influence of chosen deformations on the bandgaps.In the frame of this thesis, simulations were performed using the Vienna Ab Initio Simulation Package (VASP), a density functional theory (DFT) code that allows an insight into the mechanical and electronic properties of these materials.

AB - In recent years, materials research in electronics has been tied to the trend of downsizing, where the focus lies on creating smaller and smaller structures that can be integrated into electronic devices. With the advent of graphene, a two-dimensional carbon structure, new atomically thin materials have become a reality, some of which exhibit desired chemical and structural stability alongside sought-after electronic and optical properties. Among these, transition metal dichalcogenides (TMDCs), have attracted interest of the scientific community. These materials possess the chemical formula MX2, where “M” denotes any transition metal of the periodic table and “X2” represents two covalently bonded chalcogen atoms. These include Sulfur (S), Selenium (Se), Tellurium (Te), and also a combination of these.Simulation studies of the exotic properties of TMDCs have accumulated, sometimes surpass- ing experimental evidence. However, a comprehensive overview that presents the different types and fundamental properties of these materials in a clear and straightforward manner is missing. The first objective of this thesis is to close this gap, with the primary interest lying in providing an overview of the basic elastic and electronic properties of these emerg- ing materials as a function of their structure and composition. Its second objective is to investigate the effects of straining and shearing on TMDC structures, mainly to investigate the influence of chosen deformations on the bandgaps.In the frame of this thesis, simulations were performed using the Vienna Ab Initio Simulation Package (VASP), a density functional theory (DFT) code that allows an insight into the mechanical and electronic properties of these materials.

KW - TMDCs

KW - 2D-materials

KW - DFT

KW - VASP

KW - TMDCs

KW - 2D-Materialien

KW - DFT

KW - VASP

M3 - Master's Thesis

ER -