| 摘要 |
PURPOSE: To obtain a sensor which selectively detects carbon monoxide contained in a reducing gas mixture by constituting the sensor of a metal oxide element expressed by a specific formula and a pair of electrodes electrically connected to the element. CONSTITUTION: While a sensor composed of an element made of the metal oxide expressed by the formula and a pair of electrodes electrically connected to the element is exposed to an atmosphere containing carbon monoxide, the carbon monoxide is detected by measuring the electric current between the electrodes. In the formula, M and M' respectively represent a metallic ion selected out of a group composed of silicon, germanium, lead, bismuth, and their mixture and another metallic ion selected from among strontium, barium, and their mixture and a, b, c, d, e, f, and g respectively represent about 1.5 to 2, 0 to about 0.5, about 1 to 2, 0 to about 2, 0 to about 0.5, about 1 to 3, and about 6 to 12. The sensor electrodes are connected to an electric circuit which measures the conductivity of the sensor element and measure the change of the electric current caused by the conductivity change of the metal oxide element resulting from the change of the carbon monoxide concentration of the atmosphere. |
