Nanometer-sized single particles

Recently, the efficacy of LDHs as catalyst precursors for the synthesis of carbon nanotubes via catalytic chemical vapor deposition of acetylene has been reported by Duan et al. [72]. Nanometer-sized cobalt particles were prepared by calcination and subsequent reduction of a single LDH precursor containing cobalt(II) and aluminum ions homogeneously dispersed at the atomic level. Multi-walled carbon nanotubes with uniform diameters were obtained. 

Glyceryl monooleate (22) bilayer lipid membrane Nanometer-sized, single-domain, Fe304 particles attached to BLMs Electrical measurements and reflection spectroscopy were used for characterization 795... 

Anodic Reactions in Electrocatalysis -Oxidation of Carbon Monoxide, Fig. 1 Plot of a-top C-O band wavenumber versus the CO fractional surface coverage for (a) nanometer-sized Pt particles supported on pyrolytic carbon of Sibunit family and (b) Pt(557) = Pt [6(lll)x(100)] single crystal (Reproduced from Refs. [4, 17] with permission of the American Chemical Society)... 

Since the number of atoms on the surface of a bulk metal or metal oxide is extremely small compared to the number of atoms in the interior, bulk materials are often too costly to use in a catalytic process. One way to increase the effective surface area of a valuable catalytic material like a transition metal is to disperse it on a support. Figure 5.1.5 illustrates how Rh metal appears when it is supported as nanometer size crystallites on a silica carrier. High-resolution transmission electron microscopy reveals that metal crystallites, even as small as 10 nm, often expose the common low-index faces commonly associated with single crystals. However, the surface to volume ratio of the supported particles is many orders of magnitude higher than an equivalent amount of bulk metal. In fact, it is not uncommon to use catalysts with 1 nm sized metal particles where nearly every atom can be exposed to the reaction environment. 

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