(7ge) Developing Energy Materials through New Material Synthesis and Advanced Optoelectronic Characterization

The design of functional materials is a rapidly growing research area, particularly with concern to identifying new materials for energy applications. Research in materials-by-design is led by computational modeling, where thousands of new materials have been identified and screened for potential applications in areas such as photovoltaics, thermoelectrics, and energy storage. However, high-throughput synthesis and experimental characterization of theoretically identified materials is needed to realize the development of these materials and accurately verify their optoelectronic properties. Here, research is proposed for the development of unique chalcogenide and perovskite semiconductors – with particular focus on photovoltaic materials – comprised of facile solution-based processing and advanced optoelectronic characterization techniques.

My doctoral and postdoctoral research at Purdue University and Helmholtz-Zentrum Berlin has focused on the development of chalcogenide and perovskite semiconductors through nanoparticle-, solution-, and vacuum-based processing techniques. Control of material defects and transport properties has been demonstrated through unique thermal processing techniques, nano-structured device architectures, and the development of new photovoltaic materials such as Ge- and Ag-based kesterite absorbers. My current research also involves the development of solution-based ABX₃-type chalcogenide perovskites, recently identified as a promising photovoltaic absorber through computational design of materials.

In addition to material synthesis, the successful development of materials-by-design requires characterization of their intended optoelectronic properties. Such characterization is often non-trivial for early-stage/non-ideal materials, in particular when bare materials are probed in lieu of completed electronic devices. My doctoral and postdoctoral research has also focused on the development of optoelectronic characterization techniques and methodologies for non-ideal semiconductors. These techniques include electronic device measurement and simulation, as well as non-destructive probing of absorber layers for defect properties, homogeneity, and the spatial mapping of optoelectronic properties. Past research has focused on advanced quantum-efficiency, current-voltage, and impedance spectroscopy techniques for materials with non-ideal defect properties; current research is focused on developing unique photoluminescence and time-resolved photoluminescence techniques utilizing supercontinuum and multiphoton excitation.

My experiences in semiconductor material synthesis and characterization offer a unique advantage in the proposed research area of developing unique chalcogenide and perovskite semiconductors, where feedback from material characterization will be used to direct material synthesis. This research area is supported by international research initiatives, including the Materials Genome Initiative (US) and European Materials Modeling Council. Additionally, this work benefits student learning and collaboration as a multi-disciplinary approach bridging chemical engineering, materials science, chemistry, physics, and electrical engineering is required. As a faculty member I plan to continue my research to establish a world-class semiconductor research program developing energy materials, while inspiring and educating students in this area.