Redox-active charge carriers of conducting polymers as a tuner of conductivity and its potential window.
Electric conductivity of conducting polymers has been steadily enhanced towards a level worthy of being called its alias, "synthetic metal". PEDOT:PSS (poly(3,4-ethylenedioxythiophene) doped with poly(styrene sulfonate)), as a representative conducting polymer, recently reached around 3,000 S cm(-1), the value to open the possibility to replace transparent conductive oxides. The leading strategy to drive the conductivity increase is solvent annealing in which aqueous solution of PEDOT:PSS is treated with an assistant solvent such as DMSO (dimethyl sulfoxide). In addition to the conductivity enhancement, we found that the potential range in which PEDOT:PSS is conductive is tuned wider into a negative potential direction by the DMSO-annealing. Also, the increase in a redox-active fraction of charge carriers is proposed to be responsible for the enhancement of conductivity in the solvent annealing process.
i-School of Green Energy, UNIST, Ulsan 689-798, Korea.
Han-Saem
HS
Park
Seo-Jin
SJ
Ko
Jeong-Seok
JS
Park
Jin Young
JY
Kim
Hyun-Kon
HK
Song
D004121:Dimethyl Sulfoxide / Q000737:chemistry*; D004553:Electric Conductivity; D004579:Electron Transport; D006244:Hardness; D008422:Materials Testing; D010084:Oxidation-Reduction; D011137:Polystyrenes / Q000737:chemistry*; D013876:Thiophenes / Q000737:chemistry*
D011137:Polystyrenes; D013876:Thiophenes; C533756:poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate); D004121:Dimethyl Sulfoxide