title: Photosystem I on graphene as a highly transparent, photoactive electrode.
abstract: We report the fabrication of a hybrid light-harvesting electrode consisting of photosystem I (PSI) proteins extracted from spinach and adsorbed as a monolayer onto electrically contacted, large-area graphene. The transparency of graphene supports the choice of an opaque mediator at elevated concentrations. For example, we report a photocurrent of 550 nA/cm(2) from a monolayer of PSI on graphene in the presence of 20 mM methylene blue, which yields an opaque blue solution. The PSI-modified graphene electrode has a total thickness of less than 10 nm and demonstrates photoactivity that is an order of magnitude larger than that for unmodified graphene, establishing the feasibility of conjoining these nanomaterials as potential constructs in next-generation photovoltaic devices.
authors.affiliation: Interdisciplinary Materials Science Graduate Program, Vanderbilt University, Nashville, Tennessee 37235, United States.
authors.forename: Darlene
authors.initials: D
authors.lastname: Gunther
authors.forename: Gabriel
authors.initials: G
authors.lastname: LeBlanc
authors.forename: Dhiraj
authors.initials: D
authors.lastname: Prasai
authors.forename: Jamie R
authors.initials: JR
authors.lastname: Zhang
authors.forename: David E
authors.initials: DE
authors.lastname: Cliffel
authors.forename: Kirill I
authors.initials: KI
authors.lastname: Bolotin
authors.forename: G Kane
authors.initials: GK
authors.lastname: Jennings
mesh_terms: D000327:Adsorption; D004566:Electrodes; D006108:Graphite / Q000737:chemistry*; D055668:Photochemical Processes; D045331:Photosystem I Protein Complex / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D018724:Spinacia oleracea / Q000201:enzymology; D013499:Surface Properties
chemical_list: D045331:Photosystem I Protein Complex; D006108:Graphite