(CuO-CeO2)/glass cloth catalysts for selective CO oxidation in the presence of H2: The effect of the nature of the fuel component used in their surface self-propagating high-temperature synthesis on their properties
Tóm tắt
The potential of surface self-propagating high-temperature synthesis (SSHS) for obtaining (CuO-CeO2)/glass cloth catalysts is demonstrated. The dependence of the structural and catalytic properties of the catalysts on their preparation conditions (nature of the fuel component) is considered. X-ray diffraction, electron microscopy, and EXAFS data suggest that the short-term action of high temperature in the SSHS leads to the complete decomposition of the precursors and has an effect on the distribution of the resulting phases. According to H2 TPR and XPS data, the degree of dispersion of CuO and the electronic state of the reacting CuO and CeO2 phases depend on the choice of fuel. This is likely due to fuels varying in the amount of heat released in their combustion. The degree of dispersion of CuO and the total contribution from Cu1+ and Ce4+ to the electronic state of the active component increase as the standard enthalpy of combustion increases in the urea < glycerol < citric acid order. This leads to an increase in the catalytic activity of the (CuO-CeO2)/glass cloth system in selective CO oxidation.