Talk: Electrified Solid-Liquid Interface Engineering for CO2 Reduction Electrocatalysis

Stefan Ringe

Stanford University, USA

Stefan Ringe’s research focuses on a fundamental understanding of electrocatalysis at solid-liquid interfaces and the development of generalized energy storage and conversion system design principles. His interest on atomic-scale energy conversion phenomena was triggered by his time at Göttingen in the group of Alex Wodtke, where he studied non-adiabatic energy transfer of molecules on metal surfaces. After his transition to the TU Munich, he worked with Karsten Reuter on the development of a generalized ab-initio implicit solvation scheme in order to describe the effect of electrolytes on arbitrary chemical reactions. In 2017 he moved to Stanford to start his Postdoc working with Jens Nørskov and Karen Chan. His research at SUNCAT focuses on the influence of solid-liquid interface properties on electrocatalysic conversion processes with a particular focus on transport, pH, double layer electric field and cation effects on electrochemical CO2 reduction.

Abstract:

Computational and experimental screening of catalysts has been for a long time a powerful tool to optimize the performance of energy conversion systems. Regarding electrochemical CO2 reduction, however, the limits of this approach have been clearly demonstrated: As an example, the most active catalyst for C2 product generation is to date still copper which was discovered already decades ago.

In order to go beyond the catalyst screening approach, the community started to transition to a solid-liquid interface engineering approach. First studies identified various interfacial parameters to be effective for tuning conversion efficiency and product selectivity as the choice of cations, the pH, the surface morphology or the electric field. Up to now, however, most of the observed effects have been not well understood and generalized design principles are lacking.In this work we present a joint theoretical and experimental study on this topic.

We derive a generalized joint ab-initio continuum approach to efficiently describe electrified solid liquid interfaces. The model is utilized to discuss and explain surface morphology effects on CO2R at Ag and cation effects in various electrochemical applications. We further extend this approach by a transport model based on the Poisson-Nernst-Planck equations providing a fully coupled micro kinetic-transport approach  based on ab-initio derived energetics. Using this approach, we discuss pH and electric field effects on CO2R at Au. Finally, we generalize our findings and present interesting applications utilizing the design of interface properties. 

 

Tidspunkt

tir 11 dec 18
10:00

Arrangør

DTU Fysik

Hvor

DTU Fysik
Bygning 311
Lounge/1. sal