Inkjet-Printed Sulfide-Selective Electrode

Abstract

Inkjet printing technology has emerged as an alternative manufacturing method for low-cost production of electrodes. Despite significant progress, there is still a lack in the production of ion-selective electrodes. Herein, the two-step fabrication of the first inkjet-printed sulfide-selective electrode (IPSSE) is described. The two-step fabrication consists of printing a silver electrode followed by an electrochemical deposition of sulfide to produce a second kind electrode (Ag/Ag₂S). The performance of this novel device was tested using potentiometric measurements. Nernstian response (-29.4 ± 0.3 mV·decade^-1) was obtained within concentrations of 0.03-50 mM with a response time of ∼3 s. Furthermore, river/sea-spiked environmental samples and samples from a bioreactor for sulfate reduction to sulfide were measured and compared against a commercial sensor giving no significant differences. The IPSSE described in this work showed good reproducibility and durability during daily measurements over 15 days without any special storage conditions. Considering all the current challenges in inkjet-printed ion-selective electrodes, this different fabrication approach opens a new perspective for mass production of all-solid state ion-selective electrodes.