Dynamics of charge carriers photoinduced in poly(3-dodecylthiophene)/fullerene bulk heterojunction

Magnetic and dynamics properties of mobile polarons and fullerene anion-radicals photoinduced by laser beam in the poly(3-dodecylthiophene)/fullerene bulk heterojunction were studied. The number of these charge carriers was found to decrease with the growth in the photon energy. Monotonic temperature dependence for main electron relaxation parameters was obtained. The 1D polaron diffusion along the polymer chain and the fullerene rotation was shown to follow activation Elliot hopping model and to govern by the photon energy. The deviation in activation energies for polaron and anion-radical motion and the difference in their dependence on the laser irradiation photon energy prove a non-interacting character of these charge carriers photoinduced in the polymer/fullerene bulk heterojunction. (c) 2008 Elsevier B.V. All rights reserved.