Role of the Anion on the Transport and Structure of Organic Mixed Conductors

Camila Cendra, Alexander Giovannitti, Achilleas Savva, Vishak Venkatraman, Iain McCulloch, Alberto Salleo, Sahika Inal, Jonathan Rivnay

Research output: Contribution to journalArticlepeer-review

121 Scopus citations


Organic mixed conductors are increasingly employed in electrochemical devices operating in aqueous solutions that leverage simultaneous transport of ions and electrons. Indeed, their mode of operation relies on changing their doping (oxidation) state by the migration of ions to compensate for electronic charges. Nevertheless, the structural and morphological changes that organic mixed conductors experience when ions and water penetrate the material are not fully understood. Through a combination of electrochemical, gravimetric, and structural characterization, the effects of water and anions with a hydrophilic conjugated polymer are elucidated. Using a series of sodium-ion aqueous salts of varying anion size, hydration shells, and acidity, the links between the nature of the anion and the transport and structural properties of the polymer are systematically studied. Upon doping, ions intercalate in the crystallites, permanently modifying the lattice spacings, and residual water swells the film. The polymer, however, maintains electrochemical reversibility. The performance of electrochemical transistors reveals that doping with larger, less hydrated, anions increases their transconductance but decreases switching speed. This study highlights the complexity of electrolyte-mixed conductor interactions and advances materials design, emphasizing the coupled role of polymer and electrolyte (solvent and ion) in device performance.

Original languageEnglish (US)
Article number1807034
JournalAdvanced Functional Materials
Issue number5
StatePublished - Feb 1 2019
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • General Chemistry
  • Biomaterials
  • General Materials Science
  • Condensed Matter Physics
  • Electrochemistry


  • bioelectronics
  • doping
  • organic mixed conductors
  • structure–property relationships


Dive into the research topics of 'Role of the Anion on the Transport and Structure of Organic Mixed Conductors'. Together they form a unique fingerprint.

Cite this