EAGER: Project for Preliminary Studies of Electrochemical Reduction of Carbon Dioxide: Nano-Particle and Mechanistic Studies

Case Western Reserve University, Cleveland OH

Investigators

Abstract

1047563 Savinell The electrochemical reduction of carbon dioxide with renewable electrical energy sources, or by direct photoelectrocatalytic reduction, could provide a source of chemical feedstocks and high value chemicals of the future. Fundamental to photoelectrocatalytic reduction processes are electrochemical pathways. Past research on electrochemical reduction of CO2 showed low efficiency but demonstrated some success at forming hydrocarbons and C-C bonds. This research made clear that the electrochemical reduction mechanisms are complex and only sketchily understood. Although the mechanism of CO2 reduction to high value products and fuels is uncertain, it is apparent that it requires a balance between CO adsorption, H availability, and intermediates that facilitate C-C bond coupling. Thus, catalyst selection and properties are factors, and the PI Robert Savinell of Case Western Reserve University proposes preliminary experiments on model surfaces of selected metals and composite metals that would provide evidence that tailoring electrocatalysts for CO2 reduction is a feasible approach. The activity of an electrocatalyst towards electrochemical reduction of CO2 cannot be measured through comparative voltammetry alone. Consequently, the interpretation of electrochemical data by itself can be ambiguous and misleading. Therefore, electrochemical CO2 reduction must be combined with direct product analysis. PI Savinell proposes to use a new approach, Differential Electrochemical Mass Spectrometry, for the capture and analysis of the volatile products evolving from an electrode surface as a function of potential. The current is recorded simultaneously with m/e signals so product efficiencies and selectivity can be estimated, thus providing detailed information leading to mechanistic understanding of the reactions. These experiments and the preparation of the electrocatalysts are a challenge to develop and require a focused effort, which is the basis of this EAGER award. The proposed research is designed to show that the electrocatalytic approaches and methodologies proposed are feasible and can have a major impact in understanding of electrochemical reduction of carbon dioxide. The preliminary data obtained from this research will provide the foundation of the experimental research program for the PhD dissertation studies of a chemical engineering/materials science graduate student. In addition, undergraduate students participating in this project will address experimental cell design and DEMS calibration. This EAGER project is likely to be helpful to attracting these undergraduate students to pursue graduate study because of their direct involvement in exciting experiments and socially relevant science.