PEDOTPSS as an Active Layer

Others observed a pronounced dependence of the field effect on the humidity level. In dry atmosphere almost no change of on the gate voltage was found. i 2 An electrochemical mechanism was proposed to explain the electric field dependence including the dedoping of PEDOT in the presence of water. 

A different explanation was proposed by Hsu et al. Dedoping of PEDOT was ruled out as the total number of injected ions from out of the gate into the PEDOTPSS channel was too low to explain the observed current decrease. Instead a model was favored assuming a change of percolation paths caused by rendered ion positions. A small fraction removal of mediated hopping states near the Fermi level on charge transport paths causes carriers to hop over longer distance to conduct current and therefore fp is reduced. 

Nilsson et al. created an organic transistor based on a PEDOT PSS film as the active layer that was covered by an electrolyte comprising metal ions (M+) 364 conductivity of the p-type channel was modulated by reducing or oxidizing PEDOT according to  

By applying a negative potential of only Ug= 0.1 to 1 V to the electrolyte it was possible to transfer the conductive PEDOTPSS film in its almost noncon-ductive state. The redox process was fully reversible and switching speeds in the order of seconds were achieved. 

Shirakawa, E. J. Louis, A. G. MacDiarmid, C. K. Chiang, and A. J. Heeger. 1977. Synthesis of electrically conducting organic polymers Halogen derivatives of polyacetylene, (CH). / Chem Soc, Chem Commun 578-580. 

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