Photoinitiated [corrected] charge separation in a hybrid titanium dioxide metalloporphyrin peptide material

Nat Commun. 2014 Aug 18:5:4606. doi: 10.1038/ncomms5606.

Abstract

In natural systems, electron flow is mediated by proteins that spatially organize donor and acceptor molecules with great precision. Achieving this guided, directional flow of information is a desirable feature in photovoltaic media. Here, we design self-assembled peptide materials that organize multiple electronic components capable of performing photoinduced charge separation. Two peptides, c16-AHL3K3-CO2H and c16-AHL3K9-CO2H, self-assemble into fibres and provide a scaffold capable of binding a metalloporphyrin via histidine axial ligation and mineralize titanium dioxide (TiO2) on the lysine-rich surface of the resulting fibrous structures. Electron paramagnetic resonance studies of this self-assembled material under continuous light excitation demonstrate charge separation induced by excitation of the metalloporphyrin and mediated by the peptide assembly structure. This approach to dye-sensitized semiconducting materials offers a means to spatially control the dye molecule with respect to the semiconducting material through careful, strategic peptide design.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Coloring Agents
  • Electron Spin Resonance Spectroscopy / methods
  • Electrons*
  • Histidine
  • Lysine
  • Metalloporphyrins / chemistry*
  • Models, Molecular
  • Peptides / chemistry*
  • Photochemical Processes*
  • Titanium / chemistry*

Substances

  • Coloring Agents
  • Metalloporphyrins
  • Peptides
  • titanium dioxide
  • Histidine
  • Titanium
  • Lysine