Contact doping with sub-monolayers of strong polyelectrolytes for organic photovoltaics

Gopal K. Mor, David Jones, Thinh P. Le, Zhengrong Shang, Patrick J. Weathers, Megumi K.B. Woltermann, Kiarash Vakhshouri, Bryan P. Williams, Sarah A. Tohran, Tomonori Saito, Rafael Verduzco, Alberto Salleo, Michael A. Hickner, Enrique D. Gomez

Research output: Contribution to journalArticlepeer-review

25 Scopus citations


Barriers to charge transfer at electrode-semiconductor contacts are ubiquitous and limit the applicability of organic semiconductors in electronic devices. Molecular or ionic doping near contacts can alleviate charge injection or extraction problems by enabling charge tunneling through contact barriers, but the soft nature of organic materials allows for small molecule dopants to diffuse and migrate, degrading the performance of the device and limiting effective interfacial doping. Here, it is demonstrated that contact doping in organic electronics is possible through ionic polymer dopants, which resist diffusion or migration due to their large size. Sub-monolayer deposition of non-conjugated strong polyelectrolytes, e.g., sulfonated poly(sulfone)s, at the anode-semiconductor interface of organic photovoltaics enables effi cient hole extraction at the anode. The performance of contact-doped organic photovoltaics nearly matches the performance of devices composed of traditional hole transport layers such as poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS). The degree of sulfonation of the dopant polymer and the thickness of the ionic dopant layer is shown to be critical for optimizing doping and the effi ciency of the device.

Original languageEnglish (US)
Article number1400439
JournalAdvanced Energy Materials
Issue number13
StatePublished - Sep 1 2014

All Science Journal Classification (ASJC) codes

  • Renewable Energy, Sustainability and the Environment
  • General Materials Science


Dive into the research topics of 'Contact doping with sub-monolayers of strong polyelectrolytes for organic photovoltaics'. Together they form a unique fingerprint.

Cite this