ABSTRACT
Langmuir-Blodgett (LB) method can be used to fabricate molecu-
lar films with uniform orientation of molecules. This property can
be used to achieve vectorial photoinduced electron transfer (PET)
across organic film by employing specially designed donor-acceptor
(DA) molecules. A series of porphyrin-based DA compounds was
synthesized and studied in different LB film arrangements. The
porphyrin-fullerene dyads with a face-to-face orientation of the
donor and acceptor and a short inter-chromophore distance have
demonstrated a fast (<200 fs) and efficient PET, and a long lifetime
of the charge-separated state (>100 ns). The latter was achieved
due to tight packing of the dyads, which permits charge migration
between the donors and acceptors, thus resulting in formation of
intramolecular charge-separated states in the layer. The long-living
charges can be further utilized by adding secondary donor and
acceptor layers also deposited by LB method.
