Electron microscopy and spectroscopy studies of modified titanate nanostructures

Abstract

Titanate nanotubes (TNTs), such as that of Na2Ti3O7, are investigated as alternatives to TiO2 for photocatalysis, as they combine the properties of TiO2 nanoparticles with the properties of layered titanates such as cation exchangeability and open mesoporous morphology with higher specific surface area. Recently spectroscopic investigations using XPS and Raman spectroscopy on cobalt modified TNT samples showed that the presence of the Co cations and its concentration influences the optical and photocatalytic properties. The structure, composition and morphology of the material play a significant role in their catalytic activity. In this work, aberration corrected electron microscopy (AC-TEM/STEM) along with the associated spectroscopic techniques, electron energy loss spectroscopy (EELS) and energy dispersive x-ray spectroscopy (EDS) are employed to study TNTs/cobalt modified TNTs to provide an accurate and in-depth understanding of their structure, composition and morphology of the specimen in a single experiment, from the same region, with high spatial resolution.