ITO Nanoparticle Chemiresistive Sensor for Detecting Liquid Chemicals Diluted in Brine

Abstract

Sensitivity and selectivity of eco-friendly (dissoluble in seawater) sensor has been investigated. ITO (Indium-Tin-Oxide) nanoparticle-based chemiresistive sensor was imprinted on PLA (Polylactic Acid) substrates. Sensor performances were investigated using representative analytes such as methanol (MeOH), ethanol (EtOH), and isopropyl alcohol (IPA) diluted in brine (NaCl 3.5 wt.%). The sensitivities of the fabricated sensors were found to be 57.8 × 10？3 ΔS/Δppm (MeOH), 24.3 × 10？3 ΔS/Δppm (EtOH), and 33.2 × 10？3 ΔS/Δppm (IPA), respectively. Also to investigate the selective detection performance, Cyclic Voltammetry is used. The electrochemical potentials (Eoredox) between the ITO and the analytes were determined to be 252.5？mV (MeOH), ？ 246.5？mV (EtOH), and ？ 235.8？mV (IPA), respectively. It implies that ITO nanoparticle film is able to be applied not only for the determination of analyte concentration but also for the determination of kinds of it. ？ 2022, The Korean Institute of Electrical and Electronic Material Engineers.