Moderate-temperature operable SO₂ gas sensor based on Zr⁴⁺ ion conducting solid electrolyte

Abstract

A solid electrolyte type sulfur dioxide (SO2) gas sensor that can operate at moderate temperatures was fabricated using Zr4+ ion conducting Zr39/40TaP2.9W0.1O12 solid electrolyte with 0.7La2O2SO4 − 0.3(0.8Li2SO4 + 0.2K2SO4) having a large surface area and Zr metal as the auxiliary sensing electrode and reference electrode, respectively. Since the present sensor showed a quantitative, reproducible and rapid response which obeys the theoretical Nernst relationship even at 400 °C, it is a potential on site SO2 gas sensing tool operable at moderate temperatures around 400 °C.