Organic photovoltaics with thick active layers (∼800 nm) using a high mobility polymer donor

Rather consistent power conversion efficiencies have been achieved in organic solar cells throughout a wide range of active layer thicknesses (similar to 100 nm to similar to 800 nm) by using a p-type polymer semiconductor with high hole transport mobility (similar to 1 cm(2) V-1 s(-1)) as the donor, and PC61BM as the acceptor. A comparison between standard and inverted device configurations demonstrates that the inverted configuration is more suitable for achieving thicker active layers when a high hole mobility donor is used. We attribute this to the longer hole collection path in the inverted structure, which can benefit from using a high hole mobility material. Our results will be very useful for the development of new semiconductor materials and the design of device structures for more feasible manufacturing of large area OPV devices via high speed roll-to-roll printing processes. (C) 2013 Elsevier B.V. All rights reserved.