Ordered mesoporous Cu–Mg–Al composite oxides were synthesized via the one-pot evaporation-induced self-assembly strategy. Using this method, copper was first homogeneously incorporated into the ordered mesoporous sp...Ordered mesoporous Cu–Mg–Al composite oxides were synthesized via the one-pot evaporation-induced self-assembly strategy. Using this method, copper was first homogeneously incorporated into the ordered mesoporous spinel matrix. After H2 reduction treatment,according to X-ray diffraction(XRD) and transmission electron microscopy(TEM) results, copper existed as metallic nanoparticles with the size of 6–10 nm that well decorated the parent mesoporous skeleton. The metallic nanoparticles were then re-oxidized to copper oxide when exposed to air or during CO oxidation reaction at low temperatures. Thus, copper migrated from bulk spinel phase to the surface after the reduction–oxidation treatment. Moreover, the copper on the surface was re-incorporated into the bulk spinel phase by further thermaltreatment at much higher temperature in the presence of air. The correlation between the state of copper in the mesoporous composite oxides and the catalytic performance toward CO oxidation was studied. It was found that copper existed as oxide nanoparticles on the surface of mesoporous Mg–Al skeleton is much more active than that existed as lattice Cu ions in spinel phase.展开更多
基金This work was supported by the Recruitment Program of Global Youth Experts of China, the National Natural Science Foundation of China （21403267, 21450110410）, and Shandong Postdoctoral Innovation Program （201303065）.
文摘Ordered mesoporous Cu–Mg–Al composite oxides were synthesized via the one-pot evaporation-induced self-assembly strategy. Using this method, copper was first homogeneously incorporated into the ordered mesoporous spinel matrix. After H2 reduction treatment,according to X-ray diffraction(XRD) and transmission electron microscopy(TEM) results, copper existed as metallic nanoparticles with the size of 6–10 nm that well decorated the parent mesoporous skeleton. The metallic nanoparticles were then re-oxidized to copper oxide when exposed to air or during CO oxidation reaction at low temperatures. Thus, copper migrated from bulk spinel phase to the surface after the reduction–oxidation treatment. Moreover, the copper on the surface was re-incorporated into the bulk spinel phase by further thermaltreatment at much higher temperature in the presence of air. The correlation between the state of copper in the mesoporous composite oxides and the catalytic performance toward CO oxidation was studied. It was found that copper existed as oxide nanoparticles on the surface of mesoporous Mg–Al skeleton is much more active than that existed as lattice Cu ions in spinel phase.
