The Sharp Group at the Walter Schottky Institute is devoted to fabrication and characterization of functional semiconductors and catalysts, as well as their interfaces, for applications in renewable energy conversion. A current emphasis of the group is on the discovery and development of materials and combinations of materials for driving photochemical reactions. Deposition of a range of nitride, oxynitride, and oxide thin films and nanostructures is accomplished in our group using techniques including atomic layer deposition, molecular beam epitaxy, and physical vapor deposition. These approaches allow us to precisely control the composition, structure, and phase of materials in order to elucidate energy conversion mechanisms and direct functional properties. To explore material interactions, defect properties, and chemical transformations at semiconductor-based solid/solid and solid/liquid interfaces, we utilize a suite of spectroscopic and microscopic characterization tools. Ongoing work includes fundamental studies of electronic structure and charge carrier dynamics in semiconductor photoelectrodes, investigation of interfacial phenomena in heterostructured materials, and development of multi-functional thin films that balance optical, electronic, and chemical properties.