What is the difference between nanomaterial and molecular nanotechnology?

Nanomaterials can be constructed by top down techniques, producing very small structures from larger pieces of material, for example by etching to create circuits on the surface of a silicon microchip. They may also be constructed by bottom up techniques, atom by atom or molecule by molecule. One way of doing this is self-assembly, in which the atoms or molecules arrange themselves into a structure due to their natural properties. Crystals grown for the semiconductor industry provide an example of self-assembly, as does chemical synthesis of large molecules.

Molecular nanotechnology is a term that usually describes a molecule-based Nano technological concept; that means it starts with molecules as building blocks (and therefore is a bottom-up technique).

Work in this area combines nanotechnology, chemical engineering, and materials chemistry to produce materials with novel functionality. These novel materials find use in a wide range of application such as energy production, energy storage, and catalysis

Until machinery capable of automated and industrial-scale nano-assembly can be built, the parallelism of chemical synthesis and self-assembly is necessary when controlling materials at the nanoscale.