Abstract

A novel screen-printing fabrication method was used to prepare organic electrochemical transistors (OECTs) based on poly(3,4-ethylenedioxythiophene) doped with polysterene sulfonate (PEDOT:PSS). Initially, three types of these screen-printed OECTs with a different channel and gate areas ratio were compared in terms of output characteristics, transfer characteristics, and current modulation in a phosphate buffered saline (PBS) solution. Results confirm that transistors with a gate electrode larger than the channel exhibit higher modulation. OECTs with this geometry were therefore chosen to investigate their ion-sensitive properties in aqueous solutions of cations of different sizes (sodium and rhodamine B). The effect of the gate electrode was additionally studied by comparing these all-PEDOT:PSS transistors with OECTs with the same geometry but with a non-polarizable metal gate (Ag). The operation of the all-PEDOT:PSS OECTs yields a response that is not dependent on a Na+ or rhodamine concentration. The weak modulation of these transistors can be explained assuming that PEDOT:PSS behaves like a supercapacitor. In contrast, the operation of Ag-Gate OECTs yields a response that is dependent on ion concentration due to the redox reaction taking place at the gate electrode with Cl- counter-ions. This indicates that, for cation detection, the response is maximized in OECTs with non-polarizable gate electrodes.

Details

Title
Characterization of Screen-Printed Organic Electrochemical Transistors to Detect Cations of Different Sizes
Author
Contat-Rodrigo, Laura; Perez-Fuster, Clara; Lidón-Roger, Jose Vicente; Bonfiglio, Annalisa; García-Breijo, Eduardo
First page
1599
Publication year
2016
Publication date
2016
Publisher
MDPI AG
e-ISSN
14248220
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
1831878642
Copyright
Copyright MDPI AG 2016