Development and Characterization of a Novel Low-Cost Water-Level and Water Quality Monitoring Sensor by Using Enhanced Screen Printing Technology with PEDOT:PSS

Bei Wang; Manuel Baeuscher; Xiaodong Hu; Markus Woehrmann; Katharina Becker; Nils Juergensen; Moritz Hubl; Piotr Mackowiak; Martin Schneider-Ramelow; Klaus-Dieter Lang; Ha-Duong Ngo

doi:10.3390/mi11050474

Development and Characterization of a Novel Low-Cost Water-Level and Water Quality Monitoring Sensor by Using Enhanced Screen Printing Technology with PEDOT:PSS

Micromachines (Basel). 2020 Apr 30;11(5):474. doi: 10.3390/mi11050474.

Authors

Bei Wang^{1

2}, Manuel Baeuscher^{2

3}, Xiaodong Hu^{1

2

3}, Markus Woehrmann², Katharina Becker¹, Nils Juergensen², Moritz Hubl¹, Piotr Mackowiak^{2

3}, Martin Schneider-Ramelow^{2

3}, Klaus-Dieter Lang^{2

3}, Ha-Duong Ngo^{1

2}

Affiliations

¹ University of Applied Sciences Berlin, Wilhelminenhofstr. 75A, 12459 Berlin, Germany.
² Fraunhofer Institute for Reliability and Microintegration IZM, Gustav-Meyer-Allee 25, 13355 Berlin, Germany.
³ Center of Microperipheric Technologies, Technical University Berlin, Gustav-Meyer-Allee 25, 13355 Berlin, Germany.

Abstract

A novel capacitive sensor for measuring the water-level and monitoring the water quality has been developed in this work by using an enhanced screen printing technology. A commonly used environment-friendly conductive polymer poly(3,4-ethylenedioxythiophene):poly (styrenesulfonate) (PEDOT:PSS) for conductive sensors has a limited conductivity due to its high sheet resistance. A physical treatment performed during the printing process has reduced the sheet resistance of printed PEDOT:PSS on polyethylenterephthalat (PET) substrate from 264.39 Ω/sq to 23.44 Ω/sq. The adhesion bonding force between printed PEDOT:PSS and the substrate PET is increased by using chemical treatment and tested using a newly designed adhesive peeling force test. Using the economical conductive ink PEDOT:PSS with this new physical treatment, our capacitive sensors are cost-efficient and have a sensitivity of up to 1.25 pF/mm.

Keywords: adhesive peeling force test; capacitive sensor; conductive polymer; poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS); screen printing; water quality monitoring; water-level sensor.