Structural variation and water adsorption of a SnO₂ coated carbon nanotube: A nanoscale chemical imaging study

The local chemistry and electronic structure variations of an individual carbon nanotube coated with tin oxide nanoparticles have been studied by nanoscale chemical imaging using Scanning Transmission X-ray Microscopy (STXM). Specifically, STXM images at the O and C K-edges with a spatial resolution of 30 nm have been obtained and in turn used to extract X-ray absorption near edge structures (XANES) at both edges from regions of different morphology, i.e. core/shell and side by side. A comparison of the spectra at these regions reveals their structural and bonding variation. In situ STXM with humidity control was then used to image water adsorption on the nanocomposite and its effect on the electronic structure of the nanocomposite, which is crucial for its applications.