Improved performance of non-fullerene polymer solar cells by simple structural change of asymmetric acceptor based on indenothiophene

Cheol Hun Jeong, Young Un Kim, Chang Geun Park, Suna Choi, Min Ju Cho, Dong Hoon Choi

Research output: Contribution to journalArticle

1 Citation (Scopus)


In this study, we have synthesized a new asymmetric n-type semiconducting molecule (Me-ITBD) by combining 4,4-bis(4-hexylphenyl)-7-methyl-6-(thiophen-2-yl)-4H-indeno[1,2-b]thiophene with 2-(benzo[c][1,2,5]-thiadiazol-4-yl methylene)-malononitrile and applied it to polymer solar cells. Compared to the PhITBD acceptor without methyl substituent in the 7-position of the core, Me-ITBD showed a larger torsional angle between thiophene and indenothiophene. Non-fullerene polymer solar cells (PSCs) with the methyl-substituted asymmetric acceptor Me-ITBD displayed an enhanced power conversion efficiency (PCE) of 5.75%, compared to the PSC (PCE = 1.79%) based on a PhITBD acceptor. The higher PCE value of the Me-ITBD-based PSC was ascribed to its improved device parameters, i.e. the Jsc and FF, induced by a favorable fine morphology in the active layer. By simply introducing a methyl substituent in the indenothiophene unit of the PhITBD acceptor, the PSC performance was enhanced.

Original languageEnglish
Pages (from-to)164-171
Number of pages8
JournalSynthetic Metals
Publication statusPublished - 2018 Dec 1



  • Acceptor
  • Asymmetric structure
  • Indenothiophene
  • Methyl substituent
  • Polymer solar cell
  • Power conversion efficiency

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering
  • Metals and Alloys
  • Materials Chemistry

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