Synthesis of selenophene substituted benzodithiophene and fluorinated benzothiadiazole based conjugated polymers for organic solar cell applications

Aslan S. T., Cevher D., Bolayir E., HIZALAN ÖZSOY G., UDUM Y., YILDIRIM E., ...Daha Fazla

ELECTROCHIMICA ACTA, cilt.398, 2021 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 398
  • Basım Tarihi: 2021
  • Doi Numarası: 10.1016/j.electacta.2021.139298
  • Dergi Adı: ELECTROCHIMICA ACTA
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aerospace Database, Chemical Abstracts Core, Communication Abstracts, INSPEC, Metadex, Civil Engineering Abstracts
  • Anahtar Kelimeler: Benzodithiophene, Benzothiadiazole, Fluorine substitution, Power conversion efficiency, Organic solar cell, OPEN-CIRCUIT VOLTAGE, POWER CONVERSION EFFICIENCY, BAND-GAP COPOLYMERS, PHOTOVOLTAIC PERFORMANCE, ENERGY-LEVELS, MOLECULAR DESIGN, QUINOXALINE, MORPHOLOGY, ACCEPTOR, IMPACT
  • Gazi Üniversitesi Adresli: Evet

Özet

A series of alternating conjugated copolymers which contain selenophene modified benzodithiophene and fluorine bearing benzothiadiazole have been synthesized via Stille polycondensation reaction to investigate the effect of the number of fluorine atoms substituted to the benzothiadiazole. Three different polymers, PBDTSe-BT, PBDTSe-FBT and PBDTSe-FFBT, were reported and their electrochemical, spectroelectrochemical, and photovoltaic behaviors were examined. Density functional theory calculations were performed on model tetramer structures to shed light on how substituting the fluorine atom to the acceptor building block affects the structural, electronic and optical properties of the polymers. The results of computational studies were compared with experimental studies. The structure adjustment accomplished by fluorine substitution on the benzothiadiazole moiety reveals an influence on the electronic structure of polymers with a more negative HOMO energy level. A high V-OC for the resulting photovoltaic device was examined for PBDTSe-FFBT. Difluorinated polymer PBDTSe-FFBT:PC71 BM organic solar cell exhibited the highest photovoltaic performance of 2.63% with J(SC) of 7.24 mA cm(-2), V-OC of 0.72 V and FF of 50.6%. PBDTSe-BT:PC71BM revealed the best PCE as 2.39%, and the device reached the highest efficiency up to 1.68% for PBDTSe-FBT:PC71BM. (C) 2021 Elsevier Ltd. All rights reserved.