Comparison of the Catalytic Performance and Carbon Monoxide Sensing Behavior of Pd‐SnO2 Core@Shell Nanocomposites

The catalytic activity of Pd‐SnO2 core@shell nanocomposites in the oxidation of CO and their CO‐sensing behavior were compared. For this purpose, Pd particles were placed on the inside and the outside of SnO2 hollow spheres, as demonstrated by electron tomography, X‐ray photoelectron spectroscopy, and X‐ray absorption spectroscopy. Both the sensing and catalytic effect were studied in a systematic manner on such nanocomposites, and striking differences in the catalytic performance of the nanocomposites in CO oxidation and CO and H2 sensing were found. At low temperatures, SnO2@Pd was found to be a good sensor, and the light‐off temperature was significantly lower than that of Pd@SnO2. Above the ignition temperature, CO was probably rapidly removed from the gas so that the sensing effect disappeared. This demonstrated that understanding of the sensing and catalytic behavior can help in unraveling the functional properties of core@shell and Pd‐SnO2 nanocomposites in more detail. Applause, please: The catalytic activity of Pd‐SnO2 core@shell nanocomposites in the oxidation of CO and their CO‐sensing behavior are compared. For this purpose, Pd particles are placed inside and outside SnO2 hollow spheres, as proven by various techniques. At low temperatures, SnO2@Pd is a good sensor and a good catalyst and its light‐off temperature is significantly lower than that of Pd@SnO2; at higher temperatures, the scenario changes.