(381f) CO2 Conversion in Pressure-Tunable Organic CO2-Expanded Electrolytes | AIChE

(381f) CO2 Conversion in Pressure-Tunable Organic CO2-Expanded Electrolytes

Authors 

Blakemore, J. - Presenter, University of Kansas
Subramaniam, B., University of Kansas
Leonard, K. C., The University of Kansas
Electrochemical studies of carbon dioxide (CO2) conversion with both heterogeneous and molecular catalysts are typically carried out i) in aqueous solution and ii) in a narrow range of near-ambient CO2 pressures where low CO2 solubilities can limit the rate of catalysis. In this talk, the impacts and opportunities in use of higher liquid-phase concentrations of CO2 in the context of CO2 conversion chemistry & electrochemistry will be discussed. We have previously demonstrated that multi-molar CO2 concentrations can be achieved in polar organic solvents (e.g., acetonitrile, dimethylformamide) containing supporting electrode at relatively mild pressures and ambient temperatures. We have termed these CO2-rich, electrolyte-containing solutions as CO2-eXpanded Electrolytes (CXEs) because significant volumetric expansion of the liquid phase accompanies CO2 dissolution. Insights into the performance of two model catalytic systems, polycrystalline gold and the workhorse molecular catalyst [Re(CO)3(bpy)Cl] (where bpy is 2,2′-bipyridyl), will be discussed, including analysis of cyclic voltammetry data, quantitative data regarding enhancements in the space-time yield of products, and our latest directions for improving catalysis of CO2 conversion in CXEs. As pressure-tunable CXEs can significantly intensify CO2 reduction rates over known electrocatalysts by alleviating substrate starvation, CO2 pressure and the selection of appropriate solvent appear to be crucial variables for optimization in electrocatalytic CO2 conversion.