title: Graphite-Conjugated Rhenium Catalysts for Carbon Dioxide Reduction.
abstract: Condensation of fac-Re(5,6-diamino-1,10-phenanthroline)(CO)3Cl to o-quinone edge defects on graphitic carbon surfaces generates graphite-conjugated rhenium (GCC-Re) catalysts that are highly active for CO2 reduction to CO in acetonitrile electrolyte. X-ray photoelectron and X-ray absorption spectroscopies establish the formation of surface-bound Re centers with well-defined coordination environments. GCC-Re species on glassy carbon surfaces display catalytic currents greater than 50 mA cm(-2) with 96 ± 3% Faradaic efficiency for CO production. Normalized for the number of Re active sites, GCC-Re catalysts exhibit higher turnover frequencies than that of a soluble molecular analogue, fac-Re(1,10-phenanthroline)(CO)3Cl, and turnover numbers greater than 12,000. In contrast to the molecular analogue, GCC-Re surfaces display a Tafel slope of 150 mV/decade, indicative of a catalytic mechanism involving rate-limiting one-electron transfer. This work establishes graphite-conjugation as a powerful strategy for generating well-defined, tunable, heterogeneous electrocatalysts on ubiquitous graphitic carbon surfaces.
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States.
authors.forename: Seokjoon
authors.initials: S
authors.lastname: Oh
authors.affiliation: Chemical Science and Engineering Division, Argonne National Laboratory , Argonne, Illinois 60439, United States.
authors.forename: James R
authors.initials: JR
authors.lastname: Gallagher
authors.affiliation: Chemical Science and Engineering Division, Argonne National Laboratory , Argonne, Illinois 60439, United States.|School of Chemical Engineering, Purdue University , West Lafayette, Indiana 47907, United States.
authors.forename: Jeffrey T
authors.initials: JT
authors.lastname: Miller
authors.affiliation: Department of Chemistry, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States.
authors.forename: Yogesh
authors.initials: Y
authors.lastname: Surendranath