Gold anisotropic

In addition to tire standard model systems described above, more exotic particles have been prepared witli certain unusual properties, of which we will mention a few. For instance, using seeded growtli teclmiques, particles have been developed witli a silica shell which surrounds a core of a different composition, such as particles witli magnetic [12], fluorescent [13] or gold cores [14]. Anotlier example is tliat of spheres of polytetrafluoroetliylene (PTFE), which are optically anisotropic because tire core is crystalline [15]. 

Figure C2.17.5. Transmission electron micrograph of a field of anisotropic gold nanocrystals. In tliis example, a lower magnification image of gold nanocrystals reveals tlieir anisotropic shapes and faceted surfaces [36],...

Electric-field-directed growth of gold nanorods in aqueous surfactant solutions. Advanced Functional Materials, 14, 571-579 (d) Jana, N.R. (2005) Gram-scale synthesis of soluble, near-monodisperse gold nanorods and other anisotropic nanoparticles. Small,... 

Liu, (., Cankurtaran, B., Wieczorek, L., Ford, M.J. and Cortie, M.B. (2006) Anisotropic optical properties of semitransparent coatings of gold nano-caps. Advanced Functional Materials, 16, 1457-1461. 

Silver nitrate in ammoniacal solution may be completely reduced to silver by aqueous arsenious oxide. The reduction is hindered by the presence of ammonium sulphate, owing to the decrease in concentration of the hydroxyl ions 5 neutral salts such as sodium sulphate or sodium nitrate have no effect. Similarly, auric chloride may be reduced to gold.6 At 20° C. an aqueous solution of vitreous arsenious oxide reacts 4 to 5 times as rapidly as an aqueous solution of the octahedral form 7 the greater rate of dissolution in water of the former variety has been mentioned (p. 137), but from supersaturated solutions of the two forms there is no appreciable difference in the rates of deposition. The explanation of the inferior reducing power of the crystalline variety may be that there exist anisotropic molecules which only slowly lose their anisotropic properties. An ammoniacal solution of arsenious oxide heated with cupric sulphate in a sealed tube at 100° C. causes reduction... 

Aluminum, copper, diamond, gold, silicon Anisotropic etching, isotropic etching... 

The growth of Pc-based, 1-D nanostructures on gold nanoparticles has also been achieved via vapor-phase transport, in a process in which the gold nanoparticles act as nucleation sites for the perfluorinated CuPc molecules and promote their anisotropic growth leading to very uniform, 1-D structures with high aspect ratio (Fig.28) [212],... 

Anisotropic ionic conductivities were measured by an alternating current impedance method [66, 67] for the samples forming oriented monodomains in two types of cells shown in Figure 25.10. The comb-shaped gold electrodes with thickness of... 

PVP is rarely successful at producing anisotropic gold nanoparticle structures that can be explained by the selective binding growth model, unless Ag is also present. Indeed, for the gold nanooctahedra and nanodecahedra above, PVP was present but did... 

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