title: An Electrochemical NO₂ Sensor Based on Ionic Liquid: Influence of the Morphology of the Polymer Electrolyte on Sensor Sensitivity.
abstract: A systematic study was carried out to investigate the effect of ionic liquid in solid polymer electrolyte (SPE) and its layer morphology on the characteristics of an electrochemical amperometric nitrogen dioxide sensor. Five different ionic liquids were immobilized into a solid polymer electrolyte and key sensor parameters (sensitivity, response/recovery times, hysteresis and limit of detection) were characterized. The study revealed that the sensor based on 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM][N(Tf)2]) showed the best sensitivity, fast response/recovery times, and low sensor response hysteresis. The working electrode, deposited from water-based carbon nanotube ink, was prepared by aerosol-jet printing technology. It was observed that the thermal treatment and crystallinity of poly(vinylidene fluoride) (PVDF) in the solid polymer electrolyte influenced the sensitivity. Picture analysis of the morphology of the SPE layer based on [EMIM][N(Tf)2] ionic liquid treated under different conditions suggests that the sensor sensitivity strongly depends on the fractal dimension of PVDF spherical objects in SPE. Their deformation, e.g., due to crowding, leads to a decrease in sensor sensitivity.
authors.affiliation: Department of Technologies and Measurement, Faculty of Electrical Engineering/RICE, University of West Bohemia, Plzeň 306 14, Czech Republic. kubersky@ket.zcu.cz.
authors.forename: Petr
authors.initials: P
authors.lastname: Kuberský
authors.affiliation: Department of Technologies and Measurement, Faculty of Electrical Engineering/RICE, University of West Bohemia, Plzeň 306 14, Czech Republic. zmeskal@fch.vutbr.cz.|Faculty of Chemistry, Brno University of Technology, Purkyňova 464/118, 612 00 Brno, Czech Republic. zmeskal@fch.vutbr.cz.
authors.forename: Jakub
authors.initials: J
authors.lastname: Altšmíd
authors.affiliation: Department of Technologies and Measurement, Faculty of Electrical Engineering/RICE, University of West Bohemia, Plzeň 306 14, Czech Republic. hamacek@ket.zcu.cz.
authors.forename: Aleš
authors.initials: A
authors.lastname: Hamáček
authors.affiliation: Department of Technologies and Measurement, Faculty of Electrical Engineering/RICE, University of West Bohemia, Plzeň 306 14, Czech Republic. nespurek@post.cz.
authors.forename: Stanislav
authors.initials: S
authors.lastname: Nešpůrek
authors.affiliation: Faculty of Chemistry, Brno University of Technology, Purkyňova 464/118, 612 00 Brno, Czech Republic. zmeskal@fch.vutbr.cz.
authors.forename: Oldřich
authors.initials: O
authors.lastname: Zmeškal
keywords: aerosol-jet printing; amperometric NO2 sensor; carbon nanotube; ionic liquid