Quantification and Validation of the Efficiency Enhancement Reached by Application of a Retroreflective Light Trapping Texture on a Polymer Solar Cell

摘要

Organic solar cells attract considerable attention because they potentially combine favorable efficiencies with low costs via solution processing onto flexible substrates in fast roll-to-roll production. Especially during the last few years, the power conversion efficiency of organic solar cells continues to increase thanks to improved materials and device layouts and now reaches up to 9.2% for single junction polymer devices and 12.0% for multi-junction cells based on evaporated small molecules. Even for the recent highly efficient organic solar cells a sizeable fraction of light in the absorption range of the materials is not utilized. One part will be reflected at the air-substrate or substrate-indium tin oxide (ITO) interfaces and another part will not absorbed due to the relative thin absorber layers.