Chemical and Electronic Properties of PTB7-Th and ITIC on ZnO Interfaces in Organic Solar Cells

Research output: Contribution to journalArticlepeer-review


ZnO is commonly used as a cathode interface layer in organic photovoltaics due to its capability to extract electrons from the active layer. In this work, we focused on the electronic structure of the interface between ZnO and an active layer containing poly[[2,60-4,8-di(5-ethylhexylthienyl)benzo[1,2-b:3,3-b]dithiophene][3-fluoro-2[(2-ethylhexyl)carbonyl]thieno[3,4-b]thiophenediyl]] (PTB7-Th) and 3,9-bis(2-methylene-(3-(1,1-dicyanomethylene)-indanone))-5,5,11,11-tetrakis(4-hexylphenyl)-dithieno[2,3-d:20,30-d0]-s-indaceno[1,2-b:5,6-b0]-dithiophene (ITIC). Several electron spectroscopy techniques were used to determine the energy levels of these materials at their interface. The investigations show that the energy levels of PTB7-Th and ITIC were well aligned with ZnO. It is also found that there are two dipoles that form at the PTB7-Th/ZnO interface; the first is formed directly at the PTB7-Th/ZnO interface, whereas a dipole with an opposite polarity is formed within the PTB7-Th positioned further away from the interface. The findings of this work play an important role in the factors influencing the device performance of photovoltaic devices including ZnO as an interface layer.

Original languageEnglish
Article number11811–11818
Pages (from-to)11811-11818
Number of pages8
JournalACS Sustainable Chemistry and Engineering
Issue number32
Early online date1 Aug 2023
Publication statusPublished - 14 Aug 2023


  • organic solar cells
  • PTB7-Th
  • ZnO


Dive into the research topics of 'Chemical and Electronic Properties of PTB7-Th and ITIC on ZnO Interfaces in Organic Solar Cells'. Together they form a unique fingerprint.

Cite this