Shim Lab Tour

The overarching goal of my research program is to understand charging and charge separation/recombination phenomena in materials, especially in low-dimensional systems at the nanometer length scale. Charging and charge separation/recombination are fundamental processes that govern how electronic, optoelectronic, and photovoltaic devices operate. Materials with nanometer dimensions can provide intricate control over charging and charge separation processes and allow new engineering paradigms and prospects for devices with unprecedented performance. However, ubiquitously large surface-to-volume ratio of materials in this size regime often leads to large deviations from expected properties. Understanding such unexpected behavior can in turn lead to new means of manipulating novel phenomena occurring at the nanoscale. The ability to control surface and interfacial effects is then critical in elucidating the underlying materials’ properties and in developing any future technologies. Hence, I study how charging and charge separation processes affect structure, electrical and optical properties, and chemical reactivity with special attention to the materials’ responses to variations at surfaces and interfaces. Insights gained from these studies are then exploited to develop new materials exhibiting superior properties useful for solar energy conversion and high performance nano- and macro-electronics and optoelectronics.