Carbon monoxide detection method using the same and carbon monoxide detection sensor

摘要

PROBLEM TO BE SOLVED: To provide a carbon monoxide detecting sensor by which carbon monoxide in a gas to be detected can be detected with high accuracy, in which the cleaning of an electrode is not required, by which the carbon monoxide can be detected continuously and whose production efficiency is high. ;SOLUTION: An electrode 11 and an electrode 12 which face a first treatment space 15 between an oxygen pump element 3 and an oxygen concentration cell element 4 are constituted of a material (e.g. Pt) whose catalytic activity with reference to the oxidation reaction of carbon monoxide is high. An electrode 13 which faces a second treatment space 16 by the oxygen concentration cell element 4 is constituted of a material (e.g. a Pt-Au alloy) in which the catalytic activity is low. Then, when a gas, to be detected, which contains carbon monoxide and oxygen is introduced into the first treatment space 15 and the second treatment space 16, a difference in an oxygen concentration amount due to the oxidation of the carbon monoxide is generated on both sides of the oxygen concentration cell element 4, and a concentration-cell electromotive force is generated. The oxygen pump element 3 pumps the oxygen into the treatment space 16, and it controls the concentration-cell electromotive force so as to become a set desired value EC. On the basis of a current which flows to the oxygen pump element 3 at this time, the concentration of the carbon monoxide can be detected. In addition, since the electrodes 12, 13 are formed so as to be adjacent to one face of the oxygen concentration cell element 4, it is possible to obtain a carbon monoxide detecting sensor in which the number of processes is reduced and whose production efficiency can be increased.;COPYRIGHT: (C)2000,JPO