Research Projects

Layered transition metal chalcogenides (TMDs) are promising 2D semiconductors with exotic properties and interesting applications. However, they suffer from degradation in ambient conditions due to exposure to air and moisture. This proposal aims to explore alternate air-stable layered semiconductor-layered transition metal oxides, like WO₃ and MoO₃, which combine the benefits of layered chalcogenides with the chemical and thermal stability of oxides. The synthesis of layered transition metal oxides, like WO₃ and MoO₃, will be explored to understand their properties. Wafer-scale single-crystal transition metal sulfide films will be oxidized to obtain layered oxides and oxy-sulfides. Large-area films will be synthesized using liquid and solid precursors, and direct synthesis on different substrates will be used to determine the impact of the substrate on the crystallinity, phase, and microstructure of these films. A system equipped to handle oxidizing and reducing atmospheres will be constructed, with automatic recipe control and safety interlocks for controlled growth. Thermodynamic calculations will be used to predict the synthesis window and stability of these materials systems. The structural, optical, and electrical properties of these layered materials will be determined and used to correlate with optoelectronic device performance.