A CO2 sensor based on a Sc3+ conducting Sc1/3Zr2(PO4)3 solid electrolyte

A compact CO2 sensor based on the combination of newly developed trivalent Sc3+ conducting solid electrolyte, Sc1/3Zr2(PO4)3, and yttria stabilized zirconia (YSZ) was fabricated with Li2CO3 as an auxiliary electrode. The present sensor shows both a high sensitivity such as quick, theoretical and reproducible response and also a high selectivity for CO2. Furthermore, the sensor also has a long-term stability because the stable oxide (Sc2O3) is formed at the interface between Sc1/3Zr2(PO4)3 and YSZ. Since, the Sc1/3Zr2(PO4)3 is chemically stable and has a high mechanical strength, the present sensor is expected to be applied for a practical device.