title: Biological construction of single-walled carbon nanotube electron transfer pathways in dye-sensitized solar cells.
abstract: We designed and mass-produced a versatile protein supramolecule that can be used to manufacture a highly efficient dye-sensitized solar cell (DSSC). Twelve single-walled carbon-nanotube (SWNT)-binding and titanium-mineralizing peptides were genetically integrated on a cage-shaped dodecamer protein (CDT1). A process involving simple mixing of highly conductive SWNTs with CDT1 followed by TiO2 biomineralization produces a high surface-area/weight TiO2 -(anatase)-coated intact SWNT nanocomposite under environmentally friendly conditions. A DSSC with a TiO2 photoelectrode containing 0.2 wt % of the SWNT-TiO2 nanocomposite shows a current density improvement by 80% and a doubling of the photoelectric conversion efficiency. The SWNT-TiO2 nanocomposite transfers photon-generated electrons from dye molecules adsorbed on the TiO2 to the anode electrode swiftly.
authors.affiliation: Frontier Research Labs., Institute for Innovation, Ajinomoto Co., Inc. (Japan).
authors.forename: Ippei
authors.initials: I
authors.lastname: Inoue
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Watanabe
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Yamauchi
authors.forename: Yasuaki
authors.initials: Y
authors.lastname: Ishikawa
authors.forename: Hisashi
authors.initials: H
authors.lastname: Yasueda
authors.forename: Yukiharu
authors.initials: Y
authors.lastname: Uraoka
authors.forename: Ichiro
authors.initials: I
authors.lastname: Yamashita
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry*; D004396:Coloring Agents / Q000737:chemistry*; D004268:DNA-Binding Proteins / Q000737:chemistry*; D055664:Electrochemical Techniques; D046529:Microscopy, Electron, Transmission; D053761:Nanocomposites / Q000737:chemistry* / Q000648:ultrastructure; D010777:Photochemistry / Q000379:methods; D012993:Solar Energy; D013059:Spectrum Analysis, Raman; D014025:Titanium / Q000737:chemistry*
chemical_list: D001426:Bacterial Proteins; D004396:Coloring Agents; D004268:DNA-Binding Proteins; C083911:DPS protein, Bacteria; C009495:titanium dioxide; D014025:Titanium
keywords: dye-sensitized solar cells; nanotubes; protein engineering; supramolecular chemistry; titania