What is nanotechnology?(1):> 1. The Significance of the Nanoscale(2):>2. New Materials: Nanomaterials(3):>2.1 Nanomaterials(4):>3. Nanomaterial Science(5):>3.1 Nanoscale in Two Dimensions(6):>3.2 Nanoscale in Two Dimensions(cont.)(7):>3.3 Nanoscale in Three Dimensions(cont.)(8):>3.4 Nanoscale in Three Dimensions(cont.)
3. Nanomaterial Science
Nanomaterials are not simply another step in the miniaturization of materials. They often require very different production approaches. There are several processes to create nanomaterials, classified as ‘top-down’ and ‘bottom-up’. Although many nanomaterials are currently at the laboratory stage of manufacture, a few of them are being commercialised.Below we outline some examples of nanomaterials and the range of nanoscience that is aimed at understanding their properties. As will be seen, the behaviour of some nanomaterials is well understood, whereas others present greater challenges.
3.1 Nanoscale in One DimensionThin films, layers and surfacesOne-dimensional nanomaterials, such as thin films and engineered surfaces, have been developed and used for decades in fields such as electronic device manufacture, chemistry and engineering. In the silicon integrated-circuit industry, for example, many devices rely on thin films for their operation, and control of film thicknesses approaching the atomic level is routine. Monolayers (layers that are one atom or molecule deep) are also routinely made and used in chemistry. The formation and properties of these layers are reasonably well understood from the atomic level upwards, even in quite complex layers (such as lubricants). Advances are being made in the control of the composition and smoothness of surfaces, and the growth of films.Engineered surfaces with tailored properties such as large surface area or specific reactivity are used routinely in a range of applications such as in fuel cells and catalysts. The large surface area provided by nanoparticles, together with their ability to self assemble on a support surface, could be of use in all of these applications.Although they represent incremental developments, surfaces with enhanced properties should find applications throughout the chemicals and energy sectors. The benefits could surpass the obvious economic and resource savings achieved by higher activity and greater selectivity in reactors and separation processes, to enabling small-scale distributed processing (making chemicals as close as possible to the point of use). There is already a move in the chemical industry towards this. Another use could be the small-scale, on-site production of high value chemicals such as pharmaceuticals.
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