Templates metal nanowires

Dudin, P V. Snowden, M. E. Macpherson, J. V Unwin, P. R. 2011. Electrochemistry at nanoscale electrodes Individual single-walled carbon nanotobes (SWNTs) and SWNT-templated metal nanowires. 

Pena DJ, Mbindyo JKN, Carado AJ, Mallouk TE, Keating CD, Razavi B, Mayer TS (2002) Template growth of photoconductive metal-CdSe-metal nanowires. J Phys Chem B 106 7458-7462... 

Mbindyo, J.K.N., Template synthesis of metal nanowires containing monolayer molecular junctions, J. Am. Chem. Soc., 124, 4020,2002. 

There has been extensive recent use of track-etched membranes as templates. As will be discussed in detail below, these membranes are ideal for producing parallel arrays of metal nanowires or nanotubules. This is usually done via electroless metal deposition [25], but many metals have also been deposited electrochemically [26]. For example, several groups have used track-etched templates for deposition of nanowires and segmented nanowires, which they then examined for giant magnetoresistance [27-29]. Other materials templated in the pores of track etch membranes include conducting polymers [30] and polymer-metal composites [31]. 

Et-HMM (HMM-1) and Ph-HMM (or HMM-p), respectively, have a highly ordered 2D-hexagonal structure that exhibits more hydrophobic properties than the sihca FSM-16. They may work as attractive templates for metal nanowires and nanopar-tides by the hydrophobic surface-mediated reaction. 

Alumina nanotubes have been prepared by the anodic oxidation of aluminum [41] the resulting tubes have one-dimensional channels with uniform diameters of 5nm and lengths of 50-100 nm. An alumina membrane with a highly ordered nanohole array in 50-100 nm diameter has also been synthesized by long-period anodization thus these local alumina nanotubes have been tried as a template for metal nanowire formation. 

The synthesis of conductive metallic nanowires that bridged two microelectrodes separated by a gap of 12-16 im was demonstrated by the growth of a silver nanowire on a DNA template that bridged the gap (Fig. 12.26).92 Short thiolated nucleic acids (12 bases long) were attached to the microelectrodes, and these acted as sticky ends for the hybridization of /.-DNA that bridged the gap. The association of Ag+ to the phosphate groups of the template, followed by their reduction with hydroquinone under basic conditions, resulted in the formation of Ag° nanoclusters on the DNA template. The subsequent enlargement of the Ag° seeds by the catalytic reduction of Ag+ by hydroquinone, under acidic conditions, yielded continuous Ag nanowires with a width of ca. lOOnm. The nanowires revealed nonlinear I—V... 

Mbindyo Jeremiah, K. N., Mallouk Thomas, E., Mattzela James, B., Kratochvilova, I., Razavi, B., Jackson Thomas, N. Mayer Theresa, S. Template synthesis of metal nanowires containing monolayer molecular junctions. J. Am. Chem. Soc. 124, 4020-6 (2002). 

Sordan, R., M. Burghard, and K. Kern. 2001. Removable template route to metallic nanowires and nanogaps. Appl. Phys. Lett. 79 2073-2075. 

Silver nanoparticles were also synthesized inside mesoporous silica by y-irradiationd These hard templates can also be used as nanoreactors to obtain nanomaterials of controlled shapes such as metal nanowires. Ichikawa and co-workers synthesized platinum and palladium nanowires in mesoporous silica However,... 

Mesoporous alumina membranes ( anodic aluminium oxide , or AAO) are prepared by anodic oxidation of aluminium metal [1,2]. The cylindrical pores, perpendicular to the membrane surface, form hexagonal arrays of straight non-intersecting channels with pore densities up to lO Vcm. Their diameters are controllable within the range 5 - 100 nm as a linear function of anodisation voltage. These membranes are used as molecular sieves, and have also found application as templates for metallic nanowires [3,4,5,6], metal elusters and colloids [7,8], and carbon nanotubes [9,10]. 

One of the earliest studies of Au nanowire (diameter 8 nm) fabricated by electrodeposition in a 5 pm thick etched track mica was reported in 1986 [26]. Effect of weak-localization and electron-electron interaction was studied down to 0.3 K. However, in the last decade especially in the last 5 years the field of electro-deposited nanowires in templates has been intensively investigated [27]. The application of such metallic nanowires in magnetism has been reviewed [28]. 

D and 3-D metal nanowire thin films[263] with tunable 3-10 nm wire diameters have been obtained by electrodeposition into mesoporous silica thin-film templates, resulting in nanowire arrays that reflect the pore structure of the template. Removal of silica is achieved via annealing followed by etching to leave mechanically strong freestanding metal nanowire films. 

Template synthesis of tremsition metal nanowires in mesoporous materials is presented. Pt, Rh, Pt-Rh, ind Pt-Pd neuiowires tu"e synthesized in HMM-1 and FSM-16 by the photoreduction method. The bimetallic nanowires in HMM-1 are alloy crystallite with a necklace-like structure. The Pt-Pd wire/HMM-1 shows higher magnetic susceptibility at low temperature than the Pt wire. In butane hydrogenolysis, Pt-Rh wire/FSM-16 shows high selectivity to isobutane. 

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