Photovoltaic cells from a soluble pentacene derivative

Multilayer heterojunction photovoltaic cells were fabricated using a solution processable pentacene derivative as the donor layer. Upon annealing of these devices, the open circuit voltage was found to gradually increase with temperature up to 265 degrees C. Further improvement in the photovoltaic performance was achieved with the incorporation of mobile ions into the donor material for concentrations of lithium triflate up to 1.4 mg/ml. Finally, after introducing an exciton blocking layer, an optimized white-light (100 mW/cm(2)) power conversion efficiency of 0.52% was achieved. (C) 2006 Elsevier B.V. All rights reserved.