Nanosize Effect on Structural and Physical Properties of an Electrode

4 Nanosize Effect on Structural and Physical Properties of an Electrode 

When crystallite size is restricted to the range 1-100 nm, the material s structural and physical properties can be significantly different from those of bulk materials. However, it should be 

The structural properties of materials are usually evaluated by the X-ray diffraction analysis. However, the X-ray diffraction relies on coherent scattering from the spatial average of a large number of unit cells. It is, therefore, insensitive to subtle structural characteristics and symmetry changes. Therefore, X-ray diffraction analysis is just a measure of the global structure of nanocrystalline materials. To probe the local structure of nanocrystalline materials, other techniques that are sensitive to a local structure are indispensable. 

In an attempt to characterize the global and local structures of nanocrystalline LiCo02 synthesized by the hydrothermal method, we employed a combination of powder X-ray diffraction and Raman spectroscopy, as described in the following section. Raman spectroscopy is known to be sensitive to symmetry changes in LiCo02 as discussed below. Furthermore, the detailed Raman spectra have been obtained, even under hydrostatic pressure.  

Raman spectroscopy can be used to probe, at least partial, the local structure of LiCo02. 

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