High catalytic activity for CO oxidation of Co3O4 nanoparticles in SiO2 nanocapsules

In this paper, rattle-type Co3O4@SiO2 nanoparticles were prepared via thermal decomposition of Co-3[Co(CN)(6)](2)@SiO2 core-shell nanocubes. The uniform Co-3[Co(CN)(6)](2) nanocubes were coated with porous silica and then calcined at 550 degrees C for 1 h to generate a large amount of Co3O4 nanocrystals in a cube-shaped silica nanocapsule via thermal decomposition of a Co-3[Co(CN)(6)](2) nanocube. The nanorattles exhibit excellent catalytic activity for CO oxidation, the CO conversion rate reaches 100% at 150 degrees C. It is suggested that Co3O4 nanocrystals with clean surfaces were produced via this approach; moreover, the porous silica shell could protect Co3O4 nanocrystals from external contamination, which makes these novel nanostructures exhibit a remarkable catalytic performance.