title: Role of proton-coupled electron transfer in O-O bond activation.
abstract: The selective reduction of oxygen to water requires four electrons and four protons. The design of catalysts that promote oxygen reduction therefore requires the management of both electron and proton inventories. Pacman and Hangman porphyrins provide a cleft for oxygen binding, a redox shuttle for oxygen reduction, and functionality for tuning the acid-base properties of bound oxygen and its intermediates. With proper control of the proton-coupled electron transfer events, O-O bond breaking of oxygen, and more generally oxygenated substrates, may be achieved with high efficiencies. The rule set developed for oxygen reduction may be applied to a variety of other small molecule activation reactions of consequence to energy conversion.
authors.affiliation: Department of Chemistry, 6-335, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139-4307, USA.
authors.forename: Joel
authors.initials: J
authors.lastname: Rosenthal
authors.forename: Daniel G
authors.initials: DG
authors.lastname: Nocera
mesh_terms: D002384:Catalysis; D018360:Crystallography, X-Ray; D004563:Electrochemistry; D004579:Electron Transport; D006860:Hydrogen Bonding; D008958:Models, Molecular; D015394:Molecular Structure; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry*; D011166:Porphyrins / Q000138:chemical synthesis / Q000737:chemistry*; D011522:Protons
chemical_list: D011166:Porphyrins; D011522:Protons; D010100:Oxygen