Comparison between unsupported mesoporous Co3O4 and supported Co3O4 on mesoporous silica as catalysts for N2O decomposition

Abstract

Mesoporous Co3O4 (meso-Co3O4) and Co3O4 nanoparticles supported on mesoporous silica SBA-15 (Co/SBA-15) were prepared by hydrothermal synthesis and an impregnation method, respectively. Although the as-prepared meso-Co3O4 had mesopores and a higher surface area comparable to that of Co/SBA-15, its catalytic activity for N2O decomposition was much lower than that of Co3O4/SBA-15. The low catalytic activity of meso-Co3O4 mainly stems from the drastic decrease of the meso-Co3O4 surface area under the reaction condition used. On the other hand, Co/SBA-15 maintained its high surface area and mesopores with the aid of a robust silica support. This finding indicates that Co3O4 supported by a support is much more stable and efficient than meso-Co3O4 under N2O decomposition reaction conditions.