Solution-processed small molecule:fullerene bulk-heterojunction solar cells: Impedance spectroscopy deduced bulk and interfacial limits to fill-factors

Antonio Guerrero, Stephen Loser, Germà Garcia-Belmonte, Carson J. Bruns, Jeremy Smith, Hiroyuki Miyauchi, Samuel I. Stupp, Juan Bisquert, Tobin J. Marks

Research output: Contribution to journalArticle

70 Citations (Scopus)


Using impedance spectroscopy, we demonstrate that the low fill factor (FF) typically observed in small molecule solar cells is due to hindered carrier transport through the active layer and hindered charge transfer through the anode interfacial layer (IFL). By carefully tuning the active layer thickness and anode IFL in BDT(TDPP)2 solar cells, the FF is increased from 33 to 55% and the PCE from 1.9 to 3.8%. These results underscore the importance of simultaneously optimizing active layer thickness and IFL in small molecule solar cells.

Original languageEnglish
Pages (from-to)16456-16462
Number of pages7
JournalPhysical Chemistry Chemical Physics
Issue number39
Publication statusPublished - Oct 21 2013


ASJC Scopus subject areas

  • Physics and Astronomy(all)
  • Physical and Theoretical Chemistry

Cite this