Probing the efficiency of electron transfer through porphyrin-based molecular wires
Artikel i vetenskaplig tidskrift, 2007

Electron transfer over long distances is important for many future applications in molecular electronics and solar energy harvesting. In these contexts, it is of great interest to find molecular systems that are able to efficiently mediate electrons in a controlled manner over nanometer distances, that is, structures that function as molecular wires. Here we investigate a series of butadiyne-linked porphyrin oligomers with ferrocene and fullerene (C-60) terminals separated by one, two, or four porphyrin units (P-n, n = 1, 2, or 4). When the porphyrin oligomer bridges are photoexcited, long-range charge separated states are formed through a series of electron-transfer steps and the rates of photoinduced charge separation and charge recombination in these systems were elucidated using time-resolved absorption and emission measurements. The rates of long-range charge recombination, through these conjugated porphyrin oligomers, are remarkably fast (k(CR2) = 15 - 1.3 x 10(8) s(-1)) and exhibit very weak distance dependence, particularly comparing the systems with n = 2 and n = 4. The observation that the porphyrin tetramer mediates fast long-range charge transfer, over 65 angstrom, is significant for the application of these structures as molecular wires.

Författare

Mikael Winters

Chalmers, Kemi- och bioteknik, Fysikalisk kemi

E. Dahlstedt

University of Oxford

H. E. Blades

University of Oxford

C. J. Wilson

University of Oxford

M. J. Frampton

University of Oxford

Harry L. Anderson

University of Oxford

Bo Albinsson

Chalmers, Kemi- och bioteknik, Fysikalisk kemi

Journal of the American Chemical Society

0002-7863 (ISSN) 1520-5126 (eISSN)

Vol. 129 4291-4297

Ämneskategorier

Fysikalisk kemi

DOI

10.1021/ja067447d