Structural Investigations of AMS-n Mesoporous Materials by Transmission Electron Microscopy

A novel synthesis route for mesoporous silicates using anionic surfactants has been recently reported. It was advanced that materials synthesized using anionic surfactants and aminosilane groups as co-structure directing agents led to the synthesis of highly ordered, novel mesoporous materials with unprecedented structural properties. Here we present an in-depth high-resolution transmission electron microscopy (HRTEM) investigation on the structural characteristics of these novel mesoporous solids denoted AMS-n (anionic mesoporous silicas). These materials show increased order in comparison with conventional mesoporous structures as a result of the long-range periodicity of structural modulations. Structural defects formed in these materials are investigated using electron diffraction (ED) and Fourier transform (FT) diffractograms. In addition we present a new cubic mesostructure AMS-8 (space group Fd 3̄ m) . These new materials show promising new pore connectivities and morphologies making them ideal for applications ranging from catalysts' supports to gas separation, and from nanodevices to drug delivery.