The intermittent nature of renewable energy sources requires a clean, scalable means of converting and storing energy. One Earth abundant storage option is water electrolysis, storing energy in the bonds of O₂ and H₂. Photoelectrochemical (PEC) cells based on semiconductor/liquid interfaces can convert sunlight to chemical fuels without external circuitry, such as “splitting” water into O₂ and H₂ upon illumination. The efficacy of conversion depends in part on the location of the semiconductor band edges, dictating absorption, and also the rectifying properties of semiconductor–electrolyte junctions, which drives the separation of electron–hole pairs. We will present studies of model oxide photoelectrodes grown by molecular beam epitaxy (MBE) and pulsed laser deposition (PLD) that display a known crystallographic orientation, surface area, path for charge transport, and strain. PEC measurements on these heterostructures establish the intrinsic activity of oxide catalysts in a way that cannot be realized with polydisperse nanoparticle systems. Measurement of X-ray photoelectron spectroscopy at ambient pressures (AP-XPS) elucidates the relationship between adsorbates and electronic structure in situ. This fundamental insight builds understanding necessary for the design of active, earth-abundant photocatalysts that can be integrated into PEC devices for efficient conversion of solar energy into chemical fuels.

Biography: https://cbee.oregonstate.edu/people/kelsey-stoerzinger

Dr. Kelsey A. Stoerzinger is an Assistant Professor in the School of Chemical, Biological and Environmental Engineering at Oregon State University. Her research interests center on the fascinating chemistry that occurs at (photo)electrochemical interfaces and plays a critical role in dictating performance of catalysts involved in energy conversion and storage. She holds a joint appointment at Pacific Northwest National Laboratory, where she was a Linus Pauling Distinguished Postdoctoral Fellow. Kelsey completed her doctoral studies in Materials Science and Engineering from the Massachusetts Institute of Technology, supported by a National Science Foundation Graduate Research Fellowship. She received an M.Phil. in Physics from the University of Cambridge as a Churchill Scholar and a B.S. from Northwestern University.

As of 2/26, dates 5/1 and 5/8 were also possible if needed.