p-Type semiconducting nickel oxide as an efficiency-enhancing anode interfacial layer in polymer bulk-heterojunction solar cells

Michael D. Irwin, D. Bruce Buchholz, Alexander W. Hains, Robert P.H. Chang, Tobin J. Marks

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1079 Citations (Scopus)


To minimize interfacial power losses, thin (5-80 nm) layers of NiO, a p-type oxide semiconductor, are inserted between the active organic layer, poly(3-hexylthiophene) (P3HT) + [6,6]-phenyl-C61 butyric acid methyl ester (PCBM), and the ITO (tin-doped indium oxide) anode of bulk-heterojunction ITO/P3HT:PCBM/LiF/Al solar cells. The interfacial NiO layer is deposited by pulsed laser deposition directly onto cleaned ITO, and the active layer is subsequently deposited by spin-coating. Insertion of the NiO layer affords cell power conversion efficiencies as high as 5.2% and enhances the fill factor to 69% and the open-circuit voltage (Voc) to 638 mV versus an ITO/P3HT:PCBM/LiF/Al control device. The value of such hole-transporting/electron-blocking interfacial layers is clearly demonstrated and should be applicable to other organic photovoltaics.

Original languageEnglish
Pages (from-to)2783-2787
Number of pages5
JournalProceedings of the National Academy of Sciences of the United States of America
Issue number8
Publication statusPublished - Feb 26 2008



  • Interface
  • Photovoltaic
  • Solar energy

ASJC Scopus subject areas

  • General

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