(Invited) Controlling the ORR with Proton Kinetics and Non-Precious Metal Catalysts

Abstract

This talk addresses the Oxygen Reduction Reaction (ORR) a reaction important in fuel cells. We use a kinetic isotope effect analysis to more fully elucidate both the ORR and OER mechanisms for both precious metal and non-precious metal systems. We develop a new platform based on a hybrid bilayer membrane (HBM) to more generally address proton-coupled electron transfer (PCET) reactions, of which the ORR is one, and show that ORR speciation can be controlled by tuning the kinetics of proton transfer. The HBM is shown to illuminate other electrochemical processes, such as anion transport, and quinone reduction speciation. We develop new non-precious metal catalysts for the ORR based on carbon encapsulated superparamagetic Fe nanoparticles. We use surface chemistry to develop new insight into the origin of activity on these constructs.