PURPOSE: To achieve higher sensitivity of a CO2 in a CO2 sensor by adding an element of at least one member from a group of a precious metal element, a transition metal element and a typical metal element with a valence of at least 3 or 4 to a CuO-BaTiO3-based CO2 detection material.
CONSTITUTION: In a carbondioxide sensor using a CuO-BaTiO3-based CO2 detection material, a precious metal such as Ag, Pd Pt or Au, an oxide of transition metal such as NiO, Co3O4 or ZnO or an oxide of a typical metal element such as In2O3 or SnO2 is added to a CuO-BaTiO3 based CO2 detection material. Pd and Ax are the most remarkable in intensifying action and Ag is the highest. So, Ag serves as a better intensifier in a CuO-BaTiO3 sensor. It is presumed that Ag added acts on the adsorption or carbonization of CO2 in a catalytic manner, hence achieving higher sensitivity of the CuO-BaTiO3-based sensor. Baking at about 700°C enables the production of a better electrostatic capacitance type CO2 sensor stably for a long time with a higher concentration of CO2.
ISHIHARA TATSUKI
TAKITA YUSAKU
MIZUHARA YUKAKO
TAKITA YUSAKU