Two-dimensional nanostructures

Vaia, R.A., Ishii, H. and Giannelis, E.P. 1993. Synthesis and properties of two dimensional nanostructures by direct intercalation of polymer melts in layered silicates. Chemistry of Material 5 1694-1696. 

Fig. la. Atomic structure ofa two-dimensional nano-structured material. For the sake of clarity, the atoms in the centers of the crystals are indicated in black. The ones in the boundary core regions are represented by open circles. Both types of atoms are assumed to be chemically identical b Atomic arrangement in a two-dimensional glass (hard sphere model), c Atomic structure of a two-dimensional nanostructured material consisting Of elastically distorted crystallites. The distortion results from the incorporation of large solute atoms. In the vicinity of the large solute atoms, the lattice planes are curved as indicated in the crystallite on the lower left side. This is not so if all atoms have the same size as indicated in Fig. la [13]... 

In contrast to nanoscaled transition metal colloids in the zerovalent form, less is known regarding the analogous metal oxides, i.e., colloidal MO (M=metal n= 1, 2, 3, etc.). Of course, such species in solid bulk form or as immobilizates on surfaces or in solid carriers have been known for a long time in heterogeneous catalysis [4], in semiconductor technology and other areas [3, 5]. More recently special methods have been developed for their preparation in constrained environments [6], in microemulsions [7], or as one- or two-dimensional nanostructures [5d, 8]. 

The research on one-dimensional nanostructures is not as advanced as that on two-dimensional nanostructures, due to the difficulties in fabricating the device. Nevertheless, to exploit the unique possibilities of these structures, the focus has to be on peculiar properties that can lead to essential advances in functional devices. For example, the self-heating property that was recently reported can be used for the development of fully-autonomous chemical sensors. ... 

Two-dimensional nanostructures have two dimensions outside of the nanometric size range, such as nanoplates, nanosheets, and nanodisks. Graphene is a typical two-dimensional film, which is composed of a one-atom-thick planar sheet of sp -bonded carbon atoms that are densely packed into a honeycomb crystal lattice. This material exhibits a high electrical conductivity, a high surface area of over 2600 m g , an elevated chemical tolerance, and a broad electrochemical window. Therefore, they were used to form two-dimensional nanocomposites with polymers. The graphene not only increases the electrical conductivity of the polymer, but also enhance its mechanical stability. Conducting polymers with various hierarchical structures have been deposited on... 

Graphene is a two-dimensional nanostructure of carbon. It consists of a single-layer sheet of sp -bonded carbon atoms. There are various methods... 

S. Rusponi, T. Cren, N. Weiss, M. Epple, P. Buluschek, L. Claude, FI. Brune The remarkable difference between surface and step atoms in the magnetic anisotropy of two-dimensional nanostructures. Nature Mater. 2, 546-551 (2003)... 

Nonequilibrium Electron Transport in Two-Dimensional Nanostructures Modeled Using Green s Eunctions and the Einite-Element Method. 

Adapted from Lalwani G, Henslee AM, Farshid B, Lin L, Kasper FK, QinY-X, et al. Two-Dimensional Nanostructure-Reinforced Biodegradable Polymeric Nanocomposites for Bone Tissue Engineering. Biomacromolecules 2013 14 900-9, with permission. Copyright American Chemical Society, 2013. 

Adapted from Farshid B, Lalwani G, Sitharaman B. In vitro cytocompatibility of onedimensional and two-dimensional nanostructure-reinforced biodegradable polymeric nanocomposites. Journal of Biomedical Materials Research Part A 2015 103 2309-21, with permission. Copyright Wiley, 2015. 

Vaia R. A., Ishii H. and Giannehs E. P. (1993), Synthesis and Properties of Two-dimensional Nanostructures by Direct Intercalation of Polymer Melts in Layered Silicates. Chem Mater, 5,1694-6. 

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