(442a) Challenges for the Design of Membrane Electrode Reactors for Use in Water Splitting and Electrochemical Reduction of CO2

The rapidly decreasing price of renewable electricity has stimulated the development of electrochemical processes for producing chemicals and fuels. Two of the most highly explored areas are the splitting of water to produce H₂ and the reduction of CO₂ to produce ethene. Recent studies have demonstrated that to achieve current densities of > 0.1 A/cm² it is best to use membrane electrode assemblies (MEAs). An MEA consists of a polymeric cation- or anion-conducting membrane coated on one side with a cathode catalyst (for the generation of H₂ or the reduction of CO₂) and on the other with an anode catalyst (for the oxidation of water to O₂). An important measure of MEA performance is the kilowatt hours required to produce a kilogram of product. This metric is a strong function of the materials comprising the MEA and the conditions under which it is operated. This talk will illustrate how the design and operation of MEAs can be understood based on continuum models developed to simulate MEA performance and how such models can be used to guide their design to minimize the energy required to produce a kilogram of product.