Patent ID: 8641878

Claim:
An electrochemical carbon monoxide sensor for use in a gas/fire detector, said electrochemical carbon monoxide sensor being exposed to a sample gas during normal sensing operation, comprising: a housing, wherein the housing comprises a first sidewall, a second sidewall, a top wall, and a bottom wall, and wherein the first sidewall, the second sidewall, the top wall and the bottom wall define a containment region for containing a micro electrode assembly therein, and further wherein the top wall of the housing comprises a gaseous diffusion aperture; and further wherein the housing is void of a solvent reservoir; said micro electrode assembly which comprises an anode, a cathode and an ion conducting membrane, and wherein the anode and the cathode are discrete elements located on the same side of the conducting membrane, and wherein the ion conducting membrane permits ion transport between the anode and the cathode, and wherein the ion conducting membrane prevents electron conduction between the anode and the cathode, and further wherein the ion conducting membrane comprises at least one of an acid doped polybenzimidazole, an acid doped polypyridylbenzimidazole, a protic ionic liquid doped polybenzimidazole, a protic ionic liquid doped sulfonated polyimide, a polyfluorinated sulfonic acid, or combinations thereof; wherein the cathode comprises an oxygen reduction catalyst that comprises a pyrolysis product of a carbonaceous material and an organometallic coordination complex of a transition metal with a nitrogen containing macrocycle that has been deposited on the carbonaceous material; wherein the cathodic material does not materially exhibit catalytic activity for the oxidation of carbon monoxide; and wherein the anode and the cathode are configured to be exposed to the same sample gas during normal sensing operation.