Impact of Fluorine Atoms on Perylene Diimide Derivative for Fullerene‐Free Organic Photovoltaics. Issue 16 (21st July 2017)

• Record Type: Journal Article
• Authors: Zhao, Liang; Sun, Hua; Liu, Xiaoyuan; Liu, Changmei; Shan, Haiquan; Xia, Jiuxu; Xu, Zongxiang; Chen, Fei; Chen, Zhi‐Kuan; Huang, Wei
• Is Part Of: Chemistry, an Asian journal. Volume 12:Issue 16(2017)
• Page Start: 2052
• Page End: 2056
• Publication Date: 2017-07-21
• Subjects: bulk heterojunction morphology -- fluorination -- non-fullerene acceptor -- organic semiconductors -- perylenediimide; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/asia.201700661
• Languages: English
• ISSNs: 1861-4728

Abstract

Abstract: The incorporation of fluorine atoms in organic semiconducting materials has attracted much attention recently due to its unique function to manipulate the molecular packing, film morphology and molecular energy levels. In this work, two perylenediimide (PDI) derivatives FPDI‐CDTph and FPDI‐CDTph2F were designed and synthesized to investigate the impact of fluorination on non‐fullerene acceptors. Both FPDI‐CDTph and FPDI‐CDTph2F exhibited strong and broad absorption profiles, suitable lowest unoccupied molecular orbital (LUMO) and highest occupied molecular orbital (HOMO) energy levels, and good electron transport ability. Compared with FPDI‐CDTph, the fluorinated acceptor (FPDI‐CDTph2F) afforded an optimal bulk heterojunction morphology with an interconnected and nanoscale phase separated structure that allowed more efficient exciton dissociation and balanced charge transport. Consequently, organic solar cells based on FPDI‐CDTph2F showed a much higher power conversion efficiency (PCE) of 6.03 % than that of FPDI‐CDTph based devices (4.10 %) without any post‐fabrication treatment. Abstract : Powered by the sun : Bulk heterojunction (BHJ) organic photovoltaics that incorporated a donor polymer PTB7‐Th and fluorinated acceptor FPDI‐CDTph2F exhibited power conversion efficiency (PCE) up to 6.03 % without any post‐treatment.