Potentiometric Cl[sub 2] Gas Sensor Using a Na[sup +] Conducting Composite NASICON-40 wt % (Na[sub 2]O-Al[sub 2]O[sub 3]-4SiO[sub 2]) Solid Electrolyte

A composite conductor of polycrystalline NASICON mixed with glassy (40 wt %) was investigated and used for a gas sensor. The densification of the solid electrolyte was improved by the addition of the glassy material. The sensor probe using the composite electrolyte and (1:1) measuring electrode produced a rapid electromotive force (EMF) change for the gas concentration below 10 ppm at above 450°C. For the low temperature of 400°C, a slow EMF response was obtained due to the side reaction between the gas and on the solid electrolyte and/or slow reduction to ion on the electrode. This sensor EMF value in air was only slightly influenced by the changing of the or gas concentration.