University of Zagreb. Faculty of Chemical Engineering and Technology.
Abstract
Predmet ovog rada bila je priprema plošne Ag|AgCl referentne elektrode printanjem ink-jet printerom. Ag tinta (NovaCentrix / ZOAK) otisnuta je na fleksibilnu površinu pomoću modificiranog ink–jet printera. Površine Ag elektroda zatim su modificirane kemijski, otopinom FeCl3 te elementarnim klorom, i elektrokemijski, cikličkom voltametrijom te potenciostatski što je rezultiralo nastankom AgCl sloja na Ag površini. Tako priređene elektrode ispitivane su potenciometrijski u neprotočnim ćelijama u nizu standardnih otopina KCl-a sa i bez podešene ionske jakosti. Ionska jakost podešena je otopinama Na2SO4 i NaNO3. Na iste elektrode nanesene su membrane na bazi ionskih tekućina (IL) i na bazi epoksida te su dulje ili kraće vrijeme močene u 10^-3 M otopini KCl-a. Potom su ponovo podvrgnute potenciometrijskim mjerenjima unutar neprotočne ćelije u nizu istih standardnih otopina. Također, testirana je i stabilnost pojedine referentne elektrode u 10^-3 M otopini KCl-a s podešenom ionskom jakosti kako bi se pratio odziv elektrode (potencijal) u vremenu. Najbolje rezultate pokazala je referentna elektroda dobivena modifikacijom sa željezovim (III) kloridom i IL membranom nakon petodnevnog kondicioniranja.In this work an alternative strategy for manufacturing all-solid-state reference electrodes was carried out. Planar Ag electrodes were printed using ink-jet printer which was followed by surface modification. The modification processes involved electrochemical potentiostatic and potentiodynamic methods such as cycliyc voltammetry, and also chemical methods where FeCl3 an Cl2 were used in order to obtain AgCl thin layer on the printed Ag electrode. For keeping a steady potential of quasi-reference electrodes, two kinds of membranes were prepared, first one based on ionic liquids (IL) and the second one based on epoxy resin. Potentiometric measurements were applied for calibration curves determination of printed Ag|AgCl electrodes with and without membrane. Measurements were performed in KCl standard solutions prepared in 50 mM solution of Na2SO4 and NaNO3. Electrode with IL-based membrane, the surface of which was previously modified with FeCl3 solution, exhibited the best potential stability among all other manufactured electrodes
