(418e) Electrocatalytic Water Oxidation Using Iron-Centered Organometallic Catalyst

Fe^III-TAML (tetra amido macrocyclic ligand) is a planar iron-centered molecular catalyst that has shown a robust ability to oxidize a broad range of organic molecules using hydrogen peroxide as an oxidant. More recently it has been shown to oxidize water to evolve oxygen using a chemical oxidant (Ce4+).   The oxygen evolution reaction is a potentially important reaction for the implementation of energy storage via water splitting.  We have shown that Fe^III-TAML can also electrochemically oxidize water at moderate overpotentials, demonstrating that Fe^III-TAML is a new class of molecular water oxidation electrocatalysts made from earth abundant materials.  Fe^III-TAML was immobilized onto activated carbon and subsequently deposited onto glassy carbon to form electrodes.  These electrodes were shown to electrochemically catalyze the oxygen evolution reaction in low pH aqueous solutions.  The production of O₂ was monitored in real-time using a fluorescent oxygen detector and by sampling the head space of the electrochemical cell with a gas chromatograph.