Electric current rectification by an all-organic electrochemical device

Abstract

An all-organic printed electrochemical rectifier is reported. The device is based on a patterned layer of poly(3,4-ethylenedioxythiophene) poly(styrene sulfonate) (PEDOT:PSS) that interfaces a patterned electrolyte top layer. Overlap between the electrolyte layer and the conducting polymer pattern results in the formation of two electrochemically active areas within the conducting polymer pattern. When bias voltage is applied across the conducting polymer pattern, the PEDOT in the negatively biased areas is reduced electrochemically, while the PEDOT in the positively biased area is further oxidized. Reducing PEDOT from its p-doped, pristine state to the neutral state results in a marked loss of electrical conductivity. Due to the unsymmetrical device geometry, the current through the device may be shut off for one polarity of applied bias voltage with an electrical current rectification ratio of 100 compared to the opposite polarity. The output characteristics of a corresponding half wave rectifier as well as those from a full wave bridge rectifier show stable performance at frequencies below 15 Hz.

Effects of solvents on the morphology and conductivity of poly(3,4‐ethylenedioxythiophene):Poly(styrenesulfonate) nanofibers

“…PEDOT:PSS, a conducting polymer, attracts special attention because it has electrochemical, thermal, and oxidative stability. Owing to these excellent properties, PEDOT:PSS has broad applications in areas of flexible electrodes, nanocomposites, electrochromical displays, and transistors . Recently, there has been an increased interest in PEDOT for biomedical applications due to its good oxidative stability .…”

Hybrid electronic device based on polyaniline-polyethyleneoxide junction

“…It is now well known that conducting polymers can change their conductivity drastically by switching from a doped to an undoped state. 8 The electrochemical approach has another important characteristic, namely, that the conductivity of the working channel can depend on the history of the current-potential distribution over its length, resulting in changing of their redox state and, therefore, conductivity, before the actual measurement time. 6 This can enable large ͑and reversible͒ conductivity variations under the action of the applied potential.…”

Faradaic effects in all-organic transistors

“…We believe that the experimental results are qualitatively similar to what is observed in conventional electrochemical FETs, which, typically, are also characterized by long response times driven by a slow ionic movement. 2,[26][27][28][29][30] For example, the gate bias was kept constant at V G = + 40 V for an extended period of time ͑not shown͒ until the I SD fell to very low values ͑nanoamperes or picoamperes͒. At this point, when the channel and gate sections were physically separated and visually examined, the channel appeared to be light yellow green in color rather than the expected bright-green color of emeraldine-HCl.…”