Study of hybrid solar cells made of multilayer nanocrystalline titania and poly(3-octylthiophene) or poly-(3-(2-methylhex-2-yl)-oxy-carbonyldithiophene).
Hybrid solar cells have been constructed by using nanocrystalline titania and hole-transporting polymers. Titania was deposited on fluorine-doped tin-oxide transparent electrodes in three layers: a blocking layer and two nanostructured layers, giving densely packed or open structures. Open structures produced higher currents due to better polymer penetration and larger oxide-polymer interface. Cells based on the dithiophene-unit-containing polymer gave higher open-circuit voltage. Efficient cells could be made only in the presence of a dye sensitizer and a lithium salt. Cells were neither sealed nor encapsulated and their components were deposited under ambient conditions except for the metal back electrode, which was deposited under vacuum. Cells demonstrated a transient behavior in two stages: initially an increase of both current and voltage followed by an increase in voltage and a drop in current. Both quantities were stabilized at values approximately established within a few days. These values remained stable for several months when the cells were stored in the dark.
Antoniadou
Maria
M
Engineering Science Department, University of Patras, GR-26500 Patras, Greece.
Stathatos
Elias
E
Boukos
Nikolaos
N
Stefopoulos
Andreas
A
Kallitsis
Joannis
J
Krebs
Frederik C
FC
Lianos
Panagiotis
P