We are focusing on the development of nano-functional materials/thin films synthesis and energy conversion devices. Our research involves photovoltaics (PVs) which convert sunlight to electricity without carbon-based by-products and are a vital source of clean energy. Based on physics & chemistry, we design advanced materials/interfaces to achieve high efficiencies of the next-generation energy devices beyond the record for single-junction silicon PV. Our projects will solve environmental issues including climate change by the carbon dioxide emission due to human activity.