Surface faceting of gold nanoparticles and adsorption of organic macromolecules

Dispersions of nanosized gold particles are synthesized in methyl hydroxyethyl-, carboxymethyl-, and hydroxy propylmethyl cellulose solutions by chemical reduction. Sizes of nanoparticles are determined using dynamic light scattering method. Ultrathin particle layers are prepared on the surfaces of polycrystalline gold films by self-organization technique. Characteristics of these layers and constituting particles are determined by scanning tunnel microscopy. It is shown that steps with heights of 0.7–4 nm and terraces are formed on nanoparticles. It is revealed that the height of a step depends to a greater extent on the chemical nature of employed reducer (tannin or formaldehyde) than on the nature of stabilizer (cellulose derivatives). Components of dispersion medium are selectively adsorbed on these steps.