Poster Electronic Properties of Organic Photovoltaic rr-P3HT/C60 Ordered Blend

The need for clean and renewable energy sources has recently promoted research on organic pho-tovoltaic cells (OPCs) to reduce the cost of solar energy by exploiting the large-scale and low-cost fabrication techniques associated with polymers. Photon absorption, occurring in an electron donor material, creates excitons which are dissociated into free charge carriers when encountering an in-terface with an electron acceptor material. Bulk heterojunctions of donor and acceptor are used to reduce exciton recombination in the donor and to achieve power conversion efficiencies up to 5% [1,2]. However, the efficiency of OPCs has to reach 10 % before they can be competitive in the solar cell market which is currently dominated by polycrystalline silicon [3]. One possible way to achieve such target is through the engineering of the donor-acceptor structure, which requires a better fundamental understanding of the physical processes taking place in these organic systems. A computational study on a promising donor-acceptor system is performed to investigate the in-fluence of structural order within the blend on the resulting electronic properties. The donor is regioregular head-to-tail poly(3-hexylthiophene-2,5-diyl) (rrP3HT), which self-assemble into mi-crocrystalline domains [4] of high charge carrier mobility [5], while the acceptor is buckminster-fullerene (C60), allowing an ultrafast charge transfer between the donor and the acceptor [1]. Firs