Synergistic effect as a function of preparation method in CeO2-ZrO2-SnO2 catalysts for CO oxidation and soot combustion

The development of catalysts based on environmentally desirable components is a topical challenge. In the present work, we consider the effects of the preparation method on phase composition , porous structure , nature and distribution of active sites as well as synergistic behavior of components in two series of CeO 2 -ZrO 2 -SnO 2 catalysts for soot combustion and CO oxidation . The catalysts prepared by the citrate method feature rather large SnO 2 aggregates distributed on CeO 2 and/or ZrO 2 oxides . On the contrary, the catalysts prepared by the CTAB-templated approach feature a uniform distribution of oxide species and usually show higher activity in both CO oxidation and soot combustion. In both series, the activity and characteristics of catalysts are enhanced due to the synergistic effects arising when two or more oxide components coexist in their composition, and the degree of synergy is a function of the preparation method. The features of the most active catalysts combine (1) high specific surface area and pore volume , (2) high microstrain values, (3) coexisting oxygen vacancies of different nature, (4) high H 2 consumption at low temperatures, and (5) high fraction of adsorbed active oxygen species. • Synergistic effect is a function of catalyst preparation method. • Catalysts of CeO 2 -ZrO 2 -SnO 2 series in CO oxidation and soot combustion. • CTAB-templated samples usually show higher catalytic performance compared to those of citrate series. • Most active catalysts combine high textural properties and developed defect structure.