Detection of CO in a reducing, hydrous environment using CuBr as electrolyte

The resistance changes of CuBr upon exposure to carbon monoxide (CO) are explored as the sensing principle in this study. X-ray diffraction and thermal analysis were used to characterize the CuBr. Thick-films of CuBr deposited on an alumina substrate with gold interdigitated electrodes were used as the sensing element. Interaction with CO led to decrease in electrical resistance of the films. The presence of H2 in the background gas did not influence the resistance. Humidity, on the other hand did change the background resistance, but at constant humidity, the sensor exhibited resistance changes with CO. This sensor could be useful for CO detection in the hydrated environment of polymeric-based fuel cell systems that use hydrocarbons.