Dispersion of MoO3 Supported on Mesoporous Sieves MCM-41
MoO3在介孔分子筛MCM-41上分散和存在状态的研究

MoO3 can disperse onto the surface of mesoporous sieves MCM-41 by calcining the physical mixtures of MoO3 and MCM-41 at 773K. The state of active component MoO3 on ordered mesoporous MCM-41 was studied by TEM and SAED along with XRD, N2 sorption isotherms and BJH pore size distribution. The change for MCM-41 structure was also studied after MoO3 dispersed onto MCM-41. The results show that the XRD peaks of bulk MoO3 disappear completely when the loading of MoO3 is less than the monolayer dispersion capacity. The dispersed MoO3 can not be observed by HRTEM, while EDS spectrum evidences that there is dispersed MoO3 in the mesopores of MCM-41. It is not possible that MoO3 disperses onto MCM-41 absolutely by calcining when the content of MoO3 is more than the critical dispersion capacity. XRD, HRTEM, N2 sorption isotherms and BJH pore size distribution results all reveal that the ordered structure of MCM-41 is destroyed for the larger amount of dispersed MoO3.