CARBON DIOXIDE GAS SENSOR

摘要

PROBLEM TO BE SOLVED: To provide a CO2 gas sensor for accurately detecting a CO2 gas concen tration with a small size without ageing change of an electromotive force of the sensor. SOLUTION: In the CO2 gas sensor comprising a solid electrolyte 1 made of an alkali metal ion conductive oxide, a sensing electrode made of a metal carbonate having a dissociative balance with a CO2 gas, and a solid reference electrode 2; a non-stoichometric compound of a transition metal oxide containing an alkali metal of the same conductive species as the electrolyte 1 is used as the electrode 2.