Electrocatalysis Of Oxygen Evolution Reaction On Sriro3 Grown Using Molecular Beam Epitaxy
Electrochemical generation of oxygen via the oxygen evolution reaction (OER) is a key enabling step for many air-breathing electrochemical energy storage devices. Among the known OER catalysts, IrO2 (Ir4+: 5d5) is among the most active. In this thesis we present our measurement of the OER kinetics on single-crystal, epitaxial SrIrO3(100) synthesized using molecular-beam epitaxy on DyScO3(110). We find that by switching the host structure of the Ir4+ octahedra from edge-sharing rutile (IrO2) to corner-sharing perovskite (SrIrO3), the OER activity can increase by more than an order of magnitude. The dependence of the OER activity on the structure of Ir4+ suggests on the importance of the neighboring structure beyond a simple Ir4+-O6 unit in OER electrocatalysis. This finding highlights the need to incorporate the near-neighbor interaction consideration to the design of the future transition metal oxide electrocatalysts.
5d perovskite oxides; iridates; oxygen evolution reaction
Materials Science and Engr
M.S. of Materials Science and Engr
Master of Science
dissertation or thesis