3. Nanostructured materials and nanocomposites

3.1 Structure

We are now looking at complex materials that have an internal structure or surface structure on the nanometric scale, yet have macroscopic dimensions. We can distinguish between nanocomposites (where nanomaterials are incorporated into or onto a matrix so as to modify its properties), ultrathin film stacks, nanoporous materials (with nanometer-sized pores) and metamaterials resulting from optimized structuring in order, for example, to manipulate waves at sub-wavelength scales. Depending on the properties required, metamaterials are structured on various scales, from nanometric for optical properties to micrometric or even centimetric for microwave or radio-frequency properties.

Figure