Preparation and Comparison of M/Ce-K-O (M=Co, Ni, Cu) Nanocomposites on Catalytic Soot Combustion

Abstract

Porous nanocomposites of M/Ce-K-O (M=Co, Ni, Cu) were prepared by the citrate-gel thermal decomposition and selective reduction process, and the effect of transition metal nanoparticles on their microstructure, catalytic performance were studied by XRD, SEM, BET, XPS and TG analysis. The nanocomposites consist of the fluorite-type matrix of CeO2 nanoparticles about 13-20 nm and metallic nanoparticles ~26 nm. These nanocomposites have a nanoporous structure with high specific surface area and their pore sizes, pore structures, surface morphologies are largely affected by the dispersed nano metal species. For M/Ce-K-O (M=Co, Ni, Cu) nanocomposites, all the catalysts show a high catalytic activity for soot combustion, and among them, the Cu/Ce-K-O nanocomposite has a lowest T50 of 315 °C mainly due to a higher lattice oxygen content and a weaker Cu-O interaction intensity.

Catalytic Soot Combustion─General Concepts and Alkali Promotion

“…Detailed data used for the compilation of Figure are reported in the Table , Table , and Table S1 in the Supporting Information. Depending on their chemical composition and morphology, the catalysts were divided into six groups: platinum metal group, ,− ceria–zirconia-based, − ,,,,,,,,,,− alkali-nanostructured, ,,,,− ,,,,,,,,− ,− spinel structure, ,,,,− ,,,− perovskite structure, ,,,,,,,,,…”