CO₂ sensing properties of potentiometric CO₂ sensor using NASICON ((Na_1+XZr₂Si_XP_3-XO₁₂ : x = 1, 1.5, 2, 2.75)

Abstract

NASICON (Na1+XZr2SiXP3-XO12: x = 1, 1.5, 2, 2.75)-based potentiometric CO2 sensors attached with a metallic carbonate were fabricated and their CO2 sensing properties were investigated in the range of 250 to 2500 ppm CO2 under dry or 50 % relative humidity (RH) at 450 oC. In aging treatment the base EMF of the sensor using NASICON (X = 2.75) reached a stationary EMF value fastest of all sensors examined in dry atmosphere. It suggests for practical use that NASICON with X = 2.75 is superior to X = 2.0 used most frequently.