CO Oxidation on Ceria Studied by Electrochemical Impedance Spectroscopy

Abstract Electrochemical impedance spectroscopy technique has been widely used to analyze the electrical properties of a large number of materials. In this study, the electrical properties of CeO 2 pellets under CO oxidation conditions have been analyzed by electrochemical impedance spectroscopy. CeO 2 pellets have been prepared by a conventional precipitation method and sintered at low temperature to satisfy a compromise between large surface area and a high relative density of the pellet. The electrical properties of CeO 2 have been investigated under different atmosphere conditions such as N 2 , O 2 , CO, CO 2 , or selected combinations. The electrical sensitivity of CeO 2 to the surrounding atmosphere allows to follow the catalytic reaction as a function of the CO : O 2 ratio and temperature. The appropriate analysis of the electrical response by electrochemical impedance spectroscopy could open a new insight to monitor the catalytic response and behavior of any catalyst.