Molecular chirality and charge transfer through self-assembled scaffold monolayers.
The effect of molecular chirality on electron transmission is explored by photoelectrochemistry. Thiol-terminated chiral scaffold molecules containing a porphyrin chromophore were self-assembled on gold surfaces to form a monolayer. Incorporation of the SAM-coated gold into an electrochemical cell and illumination with visible light generated a cathodic photocurrent. When using circularly polarized light, the photocurrent displayed an asymmetry (different magnitude of photocurrent for right versus left polarization) that changed with the molecular chirality (left- or right-handedness of the scaffold). A symmetry constraint on the electronic coupling between the porphyrin and the organic scaffold is proposed as a possible mechanism for the photocurrent asymmetry.
Wei
J J
JJ
Chemistry Department, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA.
Schafmeister
C
C
Bird
G
G
Paul
A
A
Naaman
R
R
Waldeck
D H
DH