| The electrochemical carbon monoxide sensor based on polymer solid electrolyte, which could be operated not only on amperometric mode but also on potentiometric mode, was reported. The metal/ polymer composting membrane electrode, which was prepared either by chemical reduction method or by in situ impregnation-reduction method served as sensing electrode.We could conclude that there was a linear relationship between the stabilizing output voltage of the sensor and the logarithm of the volume fraction of the carbon monoxide from the research of the potentiometric carbon monoxide sensor. And the cathodic transferring coefficient calculated from the Nernst equation made it clear that the process of the electroxidation of carbon monoxide was a single electron process.The suitable manipulative voltage of the amperometric carbon monoxide sensor was studied according to the curve of current 梫oltage and the cause of the formation of stabilizing diffusion current was also discussed. What's more, we obtained the sensing capability such as response time, time constant and linearity response, etc.The investigation on the temperature characteristics of the amperometric carbon monoxide sensor indicated that there was a positiveexponential relationship between the velocity of the carbon monoxide's electrochemical oxidation reaction and the Kelvin thermometric scale. And the average temperature coefficient in the temperature range of 30-45 C was calculated, so was the apparent activation energy. While the research on the amperometric carbon monoxide sensor's humidity dependence told us that it also had a linearity relationship between sensor sensitivity and the volume fraction of carbon monoxide and by which we could gain the total progression of the electrochemical reaction of carbon monoxide and oxygen. In addition, we thought that the attenuation of the stabilizing diffusion current of the CO sensor laid in the shift of the real voltage of the Pd/air reference electrode.
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