Solution-Processed Photovoltaics with a 3,6-Bis(diarylamino)fluoren-9-ylidene Malononitrile

摘要

3,6-Bis(N,]V-dianisylamino)-fluoren-9-ylidene malononitrile (FMBDAA36) was used as an electron donor material in solution-processed organic photovoltaic devices with configuration ITO/PEDOT:PSS/(1:3[w/w] FMBDAA36:PC_(71)BM)/LiF/Al to give power conversion efficiencies up to 4.1% with open circuit voltage V_(OC) = 0.89 V, short circuit current J_(SC) = 10.35 mA cm~(-2), and fill factor FF = 44.8%. Conductive atomic force microscopy of the active layer showed granular separation of regions exhibiting easy versus difficult hole transport, consistent with bulk heterojunction type phase separation of FMBDAA36 and PC_(71)BM, respectively. Single-crystal X-ray diffraction analysis showed pure FMBDAA36 to form columnar π -stacks with a 3.3 A intermolecular spacing;