Sacrificial carbon strategy for facile fabrication of highly-dispersed cobalt-silicon nanocomposites: Insight into its performance on the CO and CH4 oxidation

Abstract The preparation of highly loaded and dispersed nanoparticle-supported catalysts is challenging and practical in industry. Here we provide a simple yet efficient strategy for the preparation of supported metal (oxide) nanoparticles. Carbonaceous layers, derived from 2-methylimidazoles ligands, were utilized as sacrificial architecture. This strategy effectively reduced the mobility and sintering of nanoparticles during the post-oxidative calcination process. The resulting material has a high loading (30 wt % theoretical contents of cobalt oxides) and small nanoparticles (∼5 nm), even that was thermally annealed at high temperature (e.g. 500 and 700 °C). In contrast to the catalyst prepared by the traditional impregnation and calcination method, the synthesized catalyst exhibits superior performance at both low (carbon monoxide oxidation) and high (methane combustion) temperatures. The excellent catalytic performance should be attributed to the strong size-dependent effect and interaction between cobalt oxides and supports. This preparation strategy paves a new way for highly loaded and dispersed supported heterogeneous catalysts.