Using Surface Science to Probe Critical Interfaces in Organic and Hybrid Systems (PReSS Talk)

This talk will address several uses of surface science for understanding critical interfaces in energy-related devices and for materials characterization. Primary emphasis will be on photoelectron spectroscopy applied to understanding interfaces in organic photovoltaics (OPV). In organic photovoltaics, where solar-to-electric conversion efficiencies are typically low, interfacial phenomena dictate the performance of the solar cell. It is therefore important to understand the interfacial chemistry and energy level alignment at these interfaces to better optimize them for increased PV performance. UV-photoelectron spectroscopy and X-ray photoelectron spectroscopy (UPS/XPS) are ideally suited to examine these interfaces. Several examples of interfacial energy level alignments will be discussed. More general applications of surface science will also be discussed including work from a collaborative effort at the National Synchrotron Light Source where NEXAFS, imaging NEXAFS, and variable energy XPS have been used for a variety of applications.