(701d) Co-Electrolysis to Achieve Energy Efficient and Economic Conversion of CO2 into Intermediates Such As CO and Ethylene (Invited)
After a brief summary of state-of-the-art electrocatalysts for the cathodic reduction of CO2 to CO and ethylene / ethanol, this talk will focus on exploring anode chemistries to help improve the economics of CO2 conversion at scale. An analysis of Gibbs free energies indicates that about 90% of the total energy required for CO2 electrolysis is consumed at the anode for the oxygen evolution reaction. In other words, 90% of the (precious renewable) energy used to drive the process is âstoredâ in oxygen for which no large market exists. In a quest to find abundantly available chemicals or waste streams that can be electro-oxidized at a much lower potential than water (thus drastically reducing the overall energy requirement of CO2 electrolysis), we identified glycerol, a large volume by-product of industrial biodiesel and soap production. Using a 2M glycerol solution as the anolyte lowers the overall cell potential by approximately 0.8 V, regardless of the CO2 electroreduction chemistry on the cathode (CO, formic acid, or ethylene/ethanol formation). The 0.8 V lower cell potential translates to a 45-53% reduction in overall energy requirement, which naturally improves the economics of CO2 electroreduction. This talk will further elaborate on glycerol oxidation as well as other chemistries that can potentially be used on the anode for economically feasible CO2 reduction through co-electrolysis approaches.
- Gold Nanoparticles on Polymer-Wrapped Carbon Nanotubes: An Efficient and Selective Catalyst for the Electroreduction of CO2, H.R.M. Jhong, C.E. Tornow, C. Kim, S. Verma, J. L. Oberst, P.S. Anderson, A.A. Gewirth, T. Fujigaya, N. Nakashima, P.J.A. Kenis, ChemPhysChem, 2017, 18 (22), 3274-3279.
- Nanoporous CopperâSilver Alloys by Additive-Controlled Electrodeposition for the Selective Electroreduction of CO2 to Ethylene and Ethanol, T.T.H. Hoang, S. Verma, S. Ma, T.T. Fister, J. Timoshenko, A.I. Frenkel, P.J.A. Kenis, and A.A. Gewirth, J. Am. Chem. Soc., 2018, accepted.