Electrolyte-gated organic field-effect transistors (EGOFETs) used as transducers and amplifiers in potentiometric sensors
have recently attracted a significant amount of scientific interest. For that reason, the fundamental prerequisites to achieve
a proper potentiometric signal amplification and transduction are examined. First, polarizable as well as non-polarizable
semiconductor- and gate-electrolyte- interface combinations are investigated by normal pulse voltammetry. The results of
these measurements are correlated with the corresponding transistor characteristics, clarifying the functional principle of
EGOFETs and the requirements for high signal amplification. In addition to a good electrical performance, the EGOFET-transducers
should also be compatible with the targeted sensing application. Accordingly, the influence of different gate
materials and electrolytes on the sensing abilities, are discussed. Even though all physical requirements are met, EGOFETs
typically exhibit irreversible degradation, if the gate potential exceeds a certain level. For that reason, EGOFETs have to
be operated using a constant source-drain operation mode which is presented by means of an H+ (pH) sensitive ion-sensor.
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