A 9,9′-spirobi[9-fluorene]-cored perylenediimide derivative and its application in organic solar cells as a non-fullerene acceptor

• Published in: Chemical communications (Cambridge, England) England), 2016-01, Vol.52 (8), p.1649-1652
• Main Authors: Yi, Jinduo, Wang, Yiling, Luo, Qun, Lin, Yi, Tan, Hongwei, Wang, Hongyu, Ma, Chang-Qi
• Format: Article
• Language: English
• Subjects: Derivatives; Energy conversion efficiency; Energy levels; Heterojunctions; Light absorption; Photovoltaic cells; Solar cells; Three dimensional
• ISSN: 1359-7345; 1364-548X
• DOI: 10.1039/c5cc08484a

A structurally non-planar molecule ( SBF-PDI 4 ) with a 9,9′-spirobi[9 H -fluorene] (SBF) core and four perylenediimides (PDIs) at the periphery was designed, synthesized and characterized. This compound shows a low-lying LUMO energy level of −4.11 eV, which is similar to that of PCBM, but with intensive light absorption ability in the range 450-550 nm. A high power conversion efficiency (PCE) of 5.34% was obtained for a solution processed bulk heterojunction solar cell (BHJSC) using SBF-PDI 4 as the electron acceptor and a low-band gap polymer poly[[4,8-bis[5-(2-ethylhexyl)thiophene-2-yl]benzo[1,2- b :4,5- b ′]dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl)carbonyl]thieno[3,4- b ]thiophenediyl]] (PTB7-Th) as the electron donor. These results demonstrate that PDI derivatives with a three dimensional molecular structure could serve as high performance electron acceptors in BHJSCs. A structurally orthogonal molecule ( SBF-PDI 4 ) with a 9,9′-spirobi[9 H -fluorene] (SBF) core and four perylenediimide (PDI) at periphery was developed for use in polymer solar cells. Proper LUMO energy level (−4.1 eV) and good light absorption ability over 450-550 nm make it an excellent non-fullerene acceptor.