1. Nanomaterials

There are three main families of nanomaterials.

• Nano-objects are materials with at least one external dimension between 1 and 100 nanometers. The number of nanometric dimensions is three for nanoparticles or aggregates, two for nanotubes or nanowires, and one for nanosheets or two-dimensional (2D) materials.

• Nanostructured materials which, while having macroscopic dimensions, have an internal or surface structure on the nanometric scale. Nanoporous materials (with pore diameters of 100 nm or less) belong to this family.

• Composite nanomaterials, which can be materials containing particles or materials at least 50% of which have one or more nanometric external dimensions.

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