A Carbon Dioxide Gas Sensor Based on Solid Electrolyte for Air Quality Control

Abstract

A CO2 sensor was set up by using Na3Zr2Si2PO12 (NASICON) as a solid electrolyte, Li2CO3 as a carbonate phase. The EMF(Electromotive force) was linear to the logarithm of CO2 concentration and hardly depended on interfering gases by using a zeolite filter. The Δ EMF(EMFAir. EMFGas) was stable even after the test of unpowered exposure to a high humidity atmosphere. The CO2 monitor in which the CO2 concentration is calculated by the Δ EMF using a new renovating system of the standard EMF was developed as a monitor for air quality control. The output of the monitor indicated a good agreement with that of the usual NDIR analyzer at the field-test in the office. © 1998, The Institute of Electrical Engineers of Japan. All rights reserved.