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The nanomesh is a new inorganic nanostructured two-dimensional material, similar to graphene. It was discovered in 2003 at the University of Zurich, Switzerland . It consists of a single layer of boron (B) and nitrogen (N) atoms, which forms by self-assembly a highly regular mesh after high-temperature exposure of a clean rhodium〔 or ruthenium surface to borazine under ultra-high vacuum. The nanomesh looks like an assembly of hexagonal pores〔In the literature different words referring to similar concepts can be found. Below a summary of them: * ''Pores, apertures, holes:'' areas of the nanomesh laying the closest to the underlying substrate due to a strong attraction. They form depressions, which are 0.05 nm deep and have a hexagonal shape. * ''Wires:'' areas of the nanomesh referring to the border of the pores, which lay the farer away to the underlying substrate and therefore represent the upper part of the nanomesh.〕 (see right image) at the nanometer (nm) scale. The distance between 2 pore centers is only of 3.2 nm, whereas each pore has a diameter of about 2 nm and is 0.05 nm deep. The lowest regions bind strongly to the underlying metal, while the wires〔 (highest regions) are only bound to the surface through strong cohesive forces within the layer itself. The boron nitride nanomesh is not only stable under vacuum,〔 air and some liquids, but also up to temperatures of 796oC (1070 K).〔 In addition it shows the extraordinary ability to trap molecules〔 and metallic clusters,〔 which have similar sizes to the nanomesh pores, forming a well-ordered array. These characteristics promise interesting applications of the nanomesh in areas like (nanocatalysis ), surface functionalisation, spintronics, quantum computing and data storage media like hard drives. ==Structure== h-BN nanomesh is a single sheet of hexagonal boron nitride, which forms on substrates like rhodium Rh(111) or ruthenium Ru(0001) crystals by a self-assembly process. The unit cell of the h-BN nanomesh consists of 13x13 BN or 12x12 Rh atoms with a lattice constant of 3.2 nm. In a cross-section it means that 13 boron or nitrogen atoms are sitting on 12 rhodium atoms. This implies a modification of the relative positions of each BN towards the substrate atoms within a unit cell, where some bonds are more attractive or repulsive than other (site selective bonding), what induces the corrugation of the nanomesh (see right image with pores and wires). 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「nanomesh」の詳細全文を読む スポンサード リンク
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