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There is increasing research interest in assemblies of chemically synthesized nanocrystal quantum dots since the self-assembly capabilities of this class of materials offer the promise of "artificial atom" solids with unique optical, electronic, and magnetic properties. [1][2][3][4][5][6][7][8][9][10][11][12][13] From a scientific viewpoint, these systems may serve as models for understanding fundamental solid-state physical phenomena at reduced energy scales (and increased length scales) compared to conventional solids. For example, effects that result from tuning of the inter-nanocrystal separation include demonstrations of insulator-to-metal transitions in compressed two-dimensional (2D) Langmuir-Blodgett monolayers of silver nanocrystals at room temperature. [14] Manipulation of inter-nanocrystal coupling from insulating to metallic states has also been

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Arrays of 28 kDa nanocrystal gold molecules behave as weakly-coupled molecular solids comprising discrete nanoscale metallic islands separated by insulating ligand barriers. The key parameters which are found to dominate charge transport are (a) the single-electron nanocrystal charging energy, governed by the core diameter, the dielectric properties of the passivating ligands and classical electrostatic coupling between neighbouring cores; (b) the inter-nanocrystal tunnel barrier resistance that arises from the insulating nature of the ligand bilayers that separate the cores; and (c) the dimensionality of the network of current-carrying paths.

Conjugated polymer based 1D nanostructures are attractive building blocks for future opto-electronic nanoscale devices and systems. However, a critical challenge remains the lack of manipulation methods that enable controlled and reliable positioning and orientation of organic nanostructures in a fast, reliable and scalable manner. To address this challenge, we explore dielectrophoretic assembly of discrete poly(9,9-dioctylfluorene) nanofibres and demonstrate site selective assembly and orientation of these fibres. Nanofibre arrays were assembled preferentially at receptor electrode edges, being aligned parallel to the applied electric field with a high order parameter fit (∼ 0.9) and exhibiting an emission dichroic ratio of ∼ 4.0. As such, the dielectrophoretic method represents a fast, reliable and scalable self-assembly approach for manipulation of 1D organic nanostructures. The ability to fabricate nanofibre arrays in this manner could be potentially important for exploration and development of future nanoscale opto-electronic devices and systems.