CAREER: Predictive design and control of the electrode/electrolyte interface for improved electrocatalysis

Clarkson University, Potsdam NY

Investigators

Abstract

Electrocatalytic processes can satisfy the growing demand for sustainable fuels and chemicals by enabling the use of renewably generated electricity in industrial chemical production. To that goal, the project explores fundamental aspects of electrocatalysis that can be deployed in electrochemical reactors (i.e., electrolyzers) to convert the waste product carbon dioxide (CO2), a greenhouse gas, into valuable ethylene, a precursor for plastics production. Beyond CO2 emissions reduction, the electrochemical approach opens the door to using electricity from wind or solar power – thus helping to close the carbon cycle. Specifically, the project focuses on improving electrolyzer performance through better understanding of the complex chemistry occurring at the interface between the electrocatalyst and a liquid or polymer electrolyte containing mobile solvent molecules and ions. The project will additionally enhance science and engineering education through demonstrations of solvent and ion effects in chemistry via the Horizons program and hands-on research experiences in both experiment and computational modeling through a yearly 2-day workshop for high-school students on sustainable chemical production at Clarkson University. The structure and composition of the electrode/electrolyte interface are known to dictate the activity, selectivity, and mechanism of electrocatalytic reactions. The overarching goals of this work are to i) understand quantitatively the chemical and physical interactions that drive near-surface spectator ion and solvent effects in electrocatalysis, ii) refine and benchmark a computationally tractable density functional theory (DFT) based approach to predict these effects, and iii) advance a novel electrochemical technique, developed by the investigator, to tune the electrode/electrolyte interface for enhanced electrocatalysis. To achieve these goals, the project combines DFT modeling with experiments on both well-defined, single-crystal electrodes, and on industrially relevant nanoparticle catalysts, to quantify the cation surface concentration and the effects of solvent-cation-adsorbate/surface interactions during CO2 electroreduction. With this understanding, the investigators will use a technique – recently developed in their laboratory - to selectively “decorate” the surface of industrially-relevant electrocatalysts with organic molecules allowing predictive tailoring of the behavior of solvent and ions at this interface. This approach will not only yield fundamental insight into cation, pH, and solvent effects in electrocatalysis, but also generate a computationally tractable approach to accurately predict these effects. Together, those efforts will identify electrocatalyst-electrolyte combinations and organic modifiers which yield improved CO2 electroreduction performance. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.