itle : Understanding trends in reaction rates in heterogeneous and electro-catalysis
Date/Time : 09-01-2023 4:00PM
Venue : Chemical Engineering Auditorium MSB 241
Speaker: Dr Sudarshan Vijay
Affiliation of the Speaker :
Postdoctoral Fellow, Department of Materials Science, University of California Berkeley
Understanding and predicting reaction rates from first-principles calculations is critical to designing materials and micro-environments for energy storage applications such as electrolyzers and Li-ion batteries.
In this talk, I will discuss how descriptor-based approaches, such as linear scaling relations, have led to a systematic understanding of trends in activity in hetero- geneous and electro-catalysis. While this approach has been successful in un- derstanding catalytic reactions, there are instances where linear scaling does not hold. To rationalize these observations, I present a model for chemisorption of small molecule adsorbates by combining a modified form of the Newns–Anderson hybridization energy with an effective orthogonalization term.1 This model re- moves the need for linearity in scaling relations, allowing for a general and quick estimation of reaction rates based on a simplified description of the adsorbate- metal bond.2 I will present applications of this method specific to electrochem- ical CO2 reduction. By combining the framework of scaling relations with a handful of computed reaction rates, I will discuss reaction pathways for CO2 electro-reduction to CO,3 illustrating that our computations are in alignment with available pH-dependent experimental activity measurements. I will con- clude by discussing potential applications for this framework in electrolyzer and Li-ion battery technologies.