title: Domain structure for an amorphous iridium-oxide water-oxidation catalyst characterized by X-ray pair distribution function analysis.
abstract: The domain structure of an amorphous, "blue layer" iridium-oxide water-oxidation catalyst film (BL) electrodeposited from the soluble precursor complex, [Cp*Ir(H2O)3]SO4, was characterized by X-ray pair distribution function (PDF) analysis. The results show that the experimental PDF can be fit remarkably well using a single Ir5O22 cluster extracted from the rutile lattice. The model includes distortions that indicate the presence of Ir(μ-O)3Ir or distorted Ir(μ-O)2Ir substructures, and hence deviations from a rutile structure. The five Ir atom cluster is suggested to represent the population-averaged distribution of metal-oxo clusters in the film. BL is found to be distinguished from other amorphous film water-oxidation catalysts because of the remarkably small domain size and homogeneity. As such, the blue layer catalyst provides a model for investigating ligand-determined metal-oxide cluster assembly and catalyst mechanism.
authors: Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, USA. tiede@anl.gov.
authors: Jier
authors: J
authors: Huang
authors: James D
authors: JD
authors: Blakemore
authors: Diego
authors: D
authors: Fazi
authors: Oleksandr
authors: O
authors: Kokhan
authors: Nathan D
authors: ND
authors: Schley
authors: Robert H
authors: RH
authors: Crabtree
authors: Gary W
authors: GW
authors: Brudvig
authors: David M
authors: DM
authors: Tiede