| 초록 |
The conjugated polymers have gained much attention because of their unique semiconducting properties in fabricating large area, flexible, and low cost electronic devices, such as organic photovoltaics(OPVs). Increasingly, power conversion efficiencies of the organic solar cells have been improved from 1% to 9% until very recently through modifying the polymer structures, processing conditions and device structures. In designing materials for polymer solar cells it is well established that apart from the chemical structure, which determines the optical band gap and energy levels, the morphology of the photoactive donor−acceptor blend plays a crucial role. The blend morphology is determined by the chemical structure and by the processing conditions used to cast the layers. Important processing parameters are donor/acceptor ratio, solvent, co-solvent, temperature, drying time, and concentration. |
