Eutectic phase behavior induced by a simple additive contributes to efficient organic solar cells

Jiehao Fu, Haiyan Chen, Peihao Huang, Qingqing Yu, Hua Tang, Shanshan Chen, Sungwoo Jung, Kuan Sun, Changduk Yang, Shirong Lu, Zhipeng Kan, Zeyun Xiao, Gang Li

Research output: Journal article publicationJournal articleAcademic researchpeer-review

5 Citations (Scopus)


Introducing a small amount of high boiling point solvent additive has been widely regarded as a feasible method to optimize the active layer morphology of organic solar cells (OSCs). However, current additives are initially developed for fullerene based OSCs and the development of additive engineering is lagging behind the development of non-fullerene acceptor based OSCs. Here, a simple and versatile solid additive, 1,4-diiodobenzene (DIB), is introduced to the non-fullerene OSCs. Due to the formation of a eutectic phase between the additive and the non-fullerene acceptor, a desired microstructure with tighter molecular stacking and more ordered molecular arrangement is achieved. As a result, DIB treated OSCs display significantly enhanced performance with a power conversion efficiency (PCE) of 17.72% for ternary device, 17.36% for binary device and 15.03% for thick-film (300 nm) device. Additional advantages of the DIB treatment include excellent device stability, toleration of a wide additive concentration range, and versatility in both polymer and small molecule OSCs. The results highlight the importance of additive engineering in high-performance OSCs and demonstrate the significance of supramolecular interactions.

Original languageEnglish
Article number105862
JournalNano Energy
Publication statusPublished - Jun 2021


  • Additive
  • Eutectic phase
  • Non-fullerene acceptor
  • Organic solar cells

ASJC Scopus subject areas

  • Renewable Energy, Sustainability and the Environment
  • Materials Science(all)
  • Electrical and Electronic Engineering

Cite this