title: Intrinsic Catalytic Activity of Graphene Defects for the Co(II/III)(bpy)3 Dye-Sensitized Solar Cell Redox Mediator.
abstract: We demonstrate that functionalized graphene, rich with lattice defects but lean with oxygen sites, catalyzes the reduction of Co(III)(bpy)3 as well as platinum does, exhibiting a rate of heterogeneous electron transfer, k0, of ∼6 × 10(-3) cm/s. We show this rate to be an order of magnitude higher than on oxygen-site-rich graphene oxide, and over 2 orders of magnitude higher than on the basal plane of graphite (as a surrogate for pristine graphene). Furthermore, dye-sensitized solar cells using defect-rich graphene monolayers perform similarly to those using platinum nanoparticles as the catalyst.
authors.affiliation: Department of Chemical and Biological Engineering, Princeton University , Princeton, New Jersey 08544, United States.
authors.forename: Joseph D
authors.initials: JD
authors.lastname: Roy-Mayhew
authors.affiliation: Department of Chemical and Biological Engineering, Princeton University , Princeton, New Jersey 08544, United States.|Vorbeck Princeton Research Center, Vorbeck Materials Corporation , 11 Deerpark Drive, Suite 203, Monmouth Junction, New Jersey 08852, United States.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Pope
authors.affiliation: Department of Chemical and Biological Engineering, Princeton University , Princeton, New Jersey 08544, United States.|Vorbeck Princeton Research Center, Vorbeck Materials Corporation , 11 Deerpark Drive, Suite 203, Monmouth Junction, New Jersey 08852, United States.
authors.forename: Christian
authors.initials: C
authors.lastname: Punckt
authors.affiliation: Department of Chemical and Biological Engineering, Princeton University , Princeton, New Jersey 08544, United States.
authors.forename: Ilhan A
authors.initials: IA
authors.lastname: Aksay
keywords: catalytic activity; cobalt redox mediator; dye-sensitized solar cell; electrocatalysis; graphene; heterogeneous electron transfer; rate constant