Highly ordered crystalline mesoporous metal oxides for hydrogen peroxide decomposition

Highly ordered mesoporous metal oxides (meso-MO _x ) such as CeO₂, Co₃O₄, Cr₂O₃, Mn₂O₃, NiO, RuO₂, SnO₂ and TiO₂ were successfully synthesized using mesoporous silica KIT-6 as a hard template via the nano-replication method. The physicochemical properties of as-prepared meso-MO _x were characterized by scanning electron microscopy, X-ray diffraction, N₂ adsorption–desorption and temperature programmed techniques. Their catalytic behavior toward H₂O₂ decomposition was investigated and compared with the corresponding bulk metal oxides (bulk-MO _x ) synthesized by the conventional precipitation method. These meso-MO _x materials exhibited much higher catalytic activities than their bulk counterparts. In particular, meso-Mn₂O₃ and meso-RuO₂ showed high activities, while meso-SnO₂ resulted in no activity toward H₂O₂ decomposition. The overall conversion of H₂O₂ followed a general order: Mn₂O₃ > RuO₂ > Co₃O₄ > CeO₂ > NiO > Cr₂O₃ > TiO₂ > SnO₂.