Nickel nanostructures

The dissimilarities between the charge states of nickel nanostructures deposited onto substrates of well-conducting p- and n-type silicon (unoxidized) were manifested in different catalytic activities in the reaction of carbon tetrachloride addition to olefins. It was shown that negatively charged nanoparticles on an n-type Si substrate have a two times higher activity, compared with positively charged particles on a p-type Si substrate (see Figure 15.10). 

In its role as a catalyst, the surface condition of the as-leached nickel nanostructure is highly important. In particular, the sites occupied on the surface of the catalyst by any residual aluminium atoms are of interest. In order to investigate the surface configuration of as-leached surfaces a Metropolis Monte Carlo (MMC) model is subsequently applied. As a starting point the MMC model exploits the nano-porous structure already predicted by the kMC approach. The MMC model aims to simulate the appearance of Al-rich surface configurations that are routinely observed in experiment. 

G.J.C. Carpenter, Z.S. Wronski, NanocrystaUine NiO and NiO-Ni(OH) composite powders prepared by thermal and mechanical dehydroxylation of nickel hydroxide, Nanostructured Mater. 11(1) (1999) 67-80. 

Moreover, nanostructured materials are useful for the construction of NE. For example, a carbon NE has been reported by sealing of a carbon nanotube under an insulator layer [27]. NE ensembles have been obtained through self-assembling of gold nanoparticles [28] and carbon nanotubes [29] at derivatized substrates. Another interesting approach is the direct growth of carbon nanotubes on electrodes with dispersed catalytic nickel nanoparticles. In this case, highly dispersed carbon NE ensembles can be constructed [30]. 

G. J. C. Carpenter, Z. S. Wronski, Nanocrystalline NiO and NiO-Ni(OH)2 Composite Powders prepared by Thermal and Mechanical Dehydroxylation of Nickel Hydroxide, Nanostructured Mater., 1999,... 

Nanostructured Li and Ni containing nickel-metal hydride batteries are widely used in cell phones, video camcorders, quartz watches, and pacemakers to name a few uses. Electrically conducting nanostructured mesoporous materials are envisaged as new materials for fuel cell applications, batteries, and ultracapacitors. 

Reetz MT, Breinbauer R, Wedemann P, Binger P (1998) Nanostructured nickel-clusters as catalysts in [3+2] cycloaddition reactions. Tetrahedron 54 1233... 

Fig. 7 Nanostructured microporous nickel with accessible pores showing the hierarchy of the pore sizes (A) micropores created by fused metal grains (B) structure of the metal grains before heat treatment (C) surface pore structure of the grains and (D) inner structure of metal grains showing the existence of a porous inner core.

Nickel containing scales exhibit higher conductivity because of the presence of trivalent nickel ions, which introduce vacancies in the lattice of the scale. Therefore, nickel-based coating can lead to superior conductivity and good protection provided that it is alloyed properly with corrosion resistant elements. Cobalt has a lower solubility in molten carbonate and electroless Co has been successfully used for a variety of corrosion-resistant applications. Electroless plating of Ni-Co gives rise to deposition of uniform layers of nanostructured material, which would result in better protection of the substrate. 

Cao, M., He, X., Chen,). and Hu, C. (2007) Self assembled nickel hydroxide three dimensional nanostructures A nanomaterial for alkaline rechargeable batteries. Crystal Growth Design, 7, 170-174. 

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