Nanoscale materials imaging

Although SEMs or ESEMs are very powerful in imaging nanoscale materials or particles, caution should be taken to avoid electron beam damage to specimen. This is particularly important when a nanomanipulation system with a force measurement device is to be used to characterise the mechanical properties of particles. Ren et al. (2007, 2008) identified that such damage depended on the electron dose and exposure time, as well as the type of materials under test, and it is extremely important to find a time window in which the damage is negligible to obtain reliable mechanical property data. 

TEM is highly suited to imaging nanoscale materials. For example, the TEM image opposite illustrates hollow spheres of boron nitride, formed from an autoclave reaction between BBrs and NaNs ... 

Nanosensois Sensors that use nanoscale materials to detect biological or chemical molecules. Scanning Probe Microscopy The use of a fine probe to scan a surface and create an image at the nanoscale. 

Bucher, J., S. Masten, B. Moudgil, et al., 2004. Developing Experimental Approaches for the Evaluation of Toxicological Interactions of Nanoscale Materials. Einal Workshop Report 3-4 November 2004, University of Florida, Gainesville, FL. Available at www.nanotoxicology.ufl.edu/workshop/images/ NanoToxWorkshop.pdf... 

There are a number of reasons for the enhanced cycle life in nanoscale materials. First, the relatively open structure of nanoscale materials seems capable of accommodating a large volume expansion during lithiation. Secondly, the conventional mechanisms for microstructural damage are often absent in nanoscale materials. Dislocations are usually unstable in crystals with nanoscale dimensions (<20 nm) due to image forces, which attract the dislocation to the surface. For brittle materials such as silicon and... 

Abstract Dye-doped polymeric micro- and nanobeads represent smart analytical tools that have become very popular recently. They enable noninvasive contactless sensing and imaging of various analytical parameters on a nanoscale and are also widely employed in composite sensing materials, in suspension arrays, and as labels. This contribution gives an overview of materials and techniques used for preparation of dye-doped polymeric beads. It also provides examples of bead materials and their applications for optical sensing and imaging. 

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