Acetylene-bridged D-A-D type small molecule comprising pyrene and diketopyrrolopyrrole for high efficiency organic solar cells

Abstract

To explore effects of acetylene-incorporation, acetylene-bridged D-A-D type small molecules ((HD/OD)-DPP-A-PY) using pyrene as a donor and diketopyrrolopyrrole as an acceptor were successfully synthesized and characterized. (HD/OD)-DPP-A-PY exhibited planar back-bone, conjugation extension, enhanced light absorption, and low HOMO energy level. Combined with the advanced properties, solution-processed OSCs based on a blend of HDDPP-A-PY as a donor and [6,6]-phenyl-C-71-butyric-acid-methyl-ester (PC70BM) as an acceptor exhibited PCEs as high as 3.15%.