Are low-coordinating anions of interest as doping agents in organic conducting polymers?

The retention of [Co(C₂B₉H₁₁)₂]^- anions in polypyrroles may be due to its large size and hydrophobicity. The electrochemical cycling of the compounds involves the insertion and de-insertion of cations during reduction and oxidation, respectively. The incorporation of [Co(C₂B₉H₁₁)₂]^- in the polypyrrole dramatically improved its overoxidation threshold, as compared with commonly used doping anions. The thermal properties of the material improved, or at least not deteriorated, as a result of the incorporation of [Co(C₂B₉H₁₁)₂]^-. An in-depth analysis carried out with Ar-ion sputtering, showed the uniform distribution of the doping agent through the whole thickness of the material.