New Materials under Extreme Environments
Extreme environments provide a much broader arena in which to search for materials with desirable properties. This is an emerging field which holds great promise for the discovery of unique materials. My group has been focusing on a number of different energy related systems including hybrid halide perovskites, transition metal chalcogenides, carbon-based nanomaterials and some disordered systems.
Glasses are thermodynamically metastable and thus prefer to devitrify when provided with enough energy to overcome the kinetic barrier to crystallization. In addition to stability concerns for material applications, research on devitrification can elucidate underlying correlations between disordered glasses and ordered crystals. Due to the absence of the well-defined dislocation defects in crystalline alloys, metallic glasses exhibit very high compressive strength, good corrosion resistance, and large elasticity.
Diamondoids are the newest members of carbon-based nanomaterials. They represent the ultimate limit for molecular fragments of bulk diamond and a unique molecular hierarchy.
Transition metal chalcogenides (TMCs)
TMCs are a class of 2D materials that have gained intense interest in recent years due to their potential application in nano-electromechanical and optoelectronic devices. Tuning their crystal and electronic structures away from the pristine states through compression allows us to access exotic physical states not available otherwise.
Hybrid halide perovskites
3D halide perovskites are crystalline materials where an extended anionic network composed of corner-sharing metal-halide octahedra is charge balanced by small organic or inorganic cations. The related 2D halide perovskites can be structurally derived from 3D perovskites by slicing along certain crystallographic directions. The compositional, structural, and electronic flexibility of the 2D and 3D halide perovskites has shown great promise and enabled diverse applications including energy and optoelectronics.