X-Ray Spectromicroscopy Studies of Nanoparticles in Aqueous Media

Abstract

X-ray microscopy is capable of imaging particles in the colloidal size range directly in their aqueous environment with high spatial resolution. It is possible to combine this with high spectral resolution for spectromicroscopy studies. Two types of microscopes are common in X-ray microscopy, the transmission X-ray microscope and the scanning transmission X-ray microscope; their setups are shown in this chapter. While the former takes high resolution images from an object within seconds or faster, the latter as an analytical instrument is suited for spectromicroscopy. As examples for visualization of the morphology, zinc containing particles and samples of clay and soil have been imaged with a transmission X-ray microscope. Images are shown from a cryo-tomography experiment based on X-ray microscopy images to obtain information about the three-dimensional structure of clusters of humic substances. The analysis of a stack of images taken with a scanning transmission X-ray microscope to bring together morphology and chemistry within a soil sample is shown.