Donor Derivative Incorporation: An Effective Strategy toward High Performance All-Small-Molecule Ternary Organic Solar Cells

Hua Tang, Tongle Xu, Cenqi Yan, Jie Gao, Hang Yin, Jie Lv, Ranbir Singh, Manish Kumar, Tainan Duan, Zhipeng Kan, Shirong Lu, Gang Li

Research output: Journal article publicationJournal articleAcademic researchpeer-review

36 Citations (Scopus)

Abstract

Thick-film all-small-molecule (ASM) organic solar cells (OSCs) are preferred for large-scale fabrication with printing techniques due to the distinct advantages of monodispersion, easy purification, and negligible batch-to-batch variation. However, ASM OSCs are typically constrained by the morphology aspect to achieve high efficiency and maintain thick film simultaneously. Specifically, synchronously manipulating crystallinity, domain size, and phase segregation to a suitable level are extremely challenging. Herein, a derivative of benzodithiophene terthiophene rhodanine (BTR) (a successful small molecule donor for thick-film OSCs), namely, BTR-OH, is synthesized with similar chemical structure and absorption but less crystallinity relative to BTR, and is employed as a third component to construct BTR:BTR-OH:PC71BM ternary devices. The power conversion efficiency (PCE) of 10.14% and fill factor (FF) of 74.2% are successfully obtained in ≈300 nm OSC, which outperforms BTR:PC71BM (9.05% and 69.6%) and BTR-OH:PC71BM (8.00% and 65.3%) counterparts, and stands among the top values for thick-film ASM OSCs. The performance enhancement results from the enhanced absorption, suppressed bimolecular/trap–assisted recombination, improved charge extraction, optimized domain size, and suitable crystallinity. These findings demonstrate that the donor derivative featuring similar chemical structure but different crystallinity provides a promising third component guideline for high-performance ternary ASM OSCs.

Original languageEnglish
Article number1901613
JournalAdvanced Science
Volume6
Issue number21
DOIs
Publication statusPublished - 1 Nov 2019

Keywords

  • morphology
  • organic solar cells
  • small molecules
  • structural similarity
  • thick films

ASJC Scopus subject areas

  • Medicine (miscellaneous)
  • Chemical Engineering(all)
  • Biochemistry, Genetics and Molecular Biology (miscellaneous)
  • Materials Science(all)
  • Engineering(all)
  • Physics and Astronomy(all)

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