Abstract

Nanostructures have become the backbone of energy harvesting and conversion due to their larger surface/bulk atomic ratio and inherently high number of surface reactive sites. Computational modeling of surface stability, reactive intermediates, and barriers has been critical for untangling spectroscopy and measured catalytic reactivity of many metal oxide catalysts. However, many models don’t include surface steps and defects present in experimental nanocatalysts. Our work focuses on accurately modelling facet edges and surface reconstruction seen in experimental systems. Computed mechanisms predict the selectivity and activity of low-index Miller facets of rutile TiO₂, reveal that surfaces other than the lowest energy surface might contribute to measured experimental reactivity. In addition, this work shows how predicted properties are dependent on the model structure. New large cluster and amorphous surface models capture the nuances of these complex experimental interfaces and their photoreactivity, which is needed to move beyond understanding experimental photocatalysis to predicting properties and rational design of new catalytic structures. 

Biography

Lisa Fredin is an assistant professor in the Department of Chemistry at Lehigh University. Prof. Fredin’s research portfolio, initiated in 2015 at NIST, draws on her background combining experiment and theory to develop computational and theoretical models of fundamental electronic properties to design materials with targeted properties. At Lehigh, the Fredin group develops models for a broad range of surface science applications, bridging physical chemistry, material science, nanoscience, and computation; as well as, probing the boundaries of the particle and wave approximations of electrons in materials.

Seminar sponsored by the Department of Chemistry and Biochemistry