Emeraldine Base Thin Film Carbon Dioxide Sensor


A thin film of emeraldine base polyaniline in NMP was cast on an interdigitated electrode and its conductivity investigated by impedance spectroscopy. The thin film responded to carbonic acid solutions of various pHs lower than 5. In general, an emeraldine base (EB) to emeraldine salt (ES) transformation occurs by protonation when the pH is less than 4. In the present case, the stages that occur prior to the onset of changes in total conductivity are detected by impedance spectroscopy. The sensor output was stable and reversible over a period of 3 months of testing.

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Correspondence to Mihai Irimia-Vladu.

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Irimia-Vladu, M., Jeffrey, W.F. Emeraldine Base Thin Film Carbon Dioxide Sensor. MRS Online Proceedings Library 889, 110 (2005). https://doi.org/10.1557/PROC-0889-W01-10

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