Electrochemistry of conductive polymers. 45. Nanoscale conductivity of PEDOT and PEDOT:PSS composite films studied by current-sensing AFM.
[Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)] (PEDOT:PSS, Baytron P) composite films were prepared under various conditions and their conductivities were studied by the current-sensing atomic force microscopy (CS-AFM) technique. Topographic and current images of pristine and additive-treated PEDOT:PSS as well as electrochemically synthesized PEDOT films were obtained in nanoscale using the CS-AFM. The as-prepared pristine PEDOT:PSS films showed a low population of conductive spots isolated by large insulating regions; both their population and the conductivities increased upon addition of a few additives to the PEDOT:PSS solution before spin-coating. From the current-voltage (I-V) traces recorded at a few representative spots of different electronic states, much improved pathways for charge percolation appeared to have been established in the additive-treated films. Electrochemically prepared PEDOT films showed much better electrical properties compared with spin-casted films of chemically prepared polymers. The conductivity of all these films was shown to be significantly enhanced by the electrochemical doping process.
Department of Chemistry, Pohang University of Science and Technology (POSTECH), Pohang, 790-784, Korea, ROK.
Hyo Joong
HJ
Lee
Joowook
J
Lee
Su-Moon
SM
Park
D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000737:chemistry*; D004553:Electric Conductivity; D004563:Electrochemistry; D008567:Membranes, Artificial; D018625:Microscopy, Atomic Force; D036103:Nanotechnology; D010316:Particle Size; D011108:Polymers / Q000737:chemistry*; D011137:Polystyrenes / Q000737:chemistry*; D013499:Surface Properties; D013876:Thiophenes / Q000737:chemistry*
D019086:Bridged Bicyclo Compounds, Heterocyclic; D008567:Membranes, Artificial; D011108:Polymers; D011137:Polystyrenes; D013876:Thiophenes; C121383:poly(3,4-ethylene dioxythiophene); C533756:poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate)