Imagine a world in which long-lasting batteries charge in seconds and “solar painted” buildings produce clean chemical fuels from abundant sunlight. Our research focuses on developing in situ spectroscopic and electrochemical imaging methods to study nanomaterials for applications in solar energy conversion and catalysis. We are interested in determining surface structure/reactivity/energy conversion correlations at the sub-nanoparticle-level and using this knowledge to rationally design functional materials. Our ultimate goal is to understand and exploit nanoparticle-nanoparticle interactions for the design of high-efficiency energy conversion devices.