Potentiometric CO2 sensor with Au,Li2CO3/Li+-electrolyte/LiMn2O4 structure

A new solid-state electrochemical cell for CO2 sensing has been set up using Li3PO4 and Li4SiO4 (LiSiPO) solid electrolyte and Li1-δMn2O4/MnO2 as reference electrode. The electromotive force (EMF), the reproducibility, and the long-term stability of the sensor signals have been examined at temperature between 400 and 500 °C exposure on dry atmosphere. The EMF is dependent on the partial pressure of CO2 and can be expressed by the Nernst equation. The cell is long-term stable at temperature as low as 450 °C and the sensor signals are reproducible with high accuracy.