Nanoscale building blocks

Functional Structures Assembled from Nanoscale Building Blocks... 

The fundamental physical properties of nanowire materials can be improved even more to surpass their bulk counterpart using precisely engineered NW heterostructures. It has been recently demonstrated that Si/Ge/Si core/shell nanowires exhibit electron mobility surpassing that of state-of-the-art technology.46 Group III-V nitride core/shell NWs of multiple layers of epitaxial structures with atomically sharp interfaces have also been demonstrated with well-controlled and tunable optical and electronic properties.47,48 Together, the studies demonstrate that semiconductor nanowires represent one of the best-defined nanoscale building block classes, with well-controlled chemical composition, physical size, and superior electronic/optical properties, and therefore, that they are ideally suited for assembly of more complex functional systems. 

FUNCTIONAL STRUCTURES ASSEMBLED FROM NANOSCALE BUILDING BLOCKS... 

Ajayan et al., 2003). Both single- and multi-walled carbon nanotubes have become ideal nanoscale-building blocks for nanoengineering. A lot of studies suggest that CNTs have extensive commercial application potential in medical chemistry and biomedical engineering. 

Hybrid Inorganic/Organic Polymers with Nanoscale Building Blocks Precursors, Processing, Properties and Applications , K.-H. Haas and K. Rose, Rev. Adv. Mater. Sci. 5, 47-52 (2003). 

Though Ceo has not (so far) found any major applications, the influence of C6o is now pervasive in chemistry and beyond.8 C6o is a kind of ideal nanoscale building block that can be picked up and manipulated with nanotechnological tools.9 Importantly, its curved, hollow structure has made us familiar with another view of carbon materials, different and complementary to that of flat sheets of carbon atoms in graphite. Ultimately, all the interest generated around such carbon allotropes has driven the research in the field and introduced the perhaps most notable representatives of the present nanoworld, carbon nanotubes (NTs). 

Fabrication is difficult, but the large-scale assembly of nanoscale building blocks into either devices (e.g. molecular electronic, or optoelectronic devices), nanostructured materials, or biomedical structures (artificial tissue, nerve-connectors, or drug delivery devices) is an even more daunting and complex problem. There are currently no satisfactory strategies... 

There are two primary types of nanoscale building blocks that may be used for further device fabrication and applications ... 

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