Preparation and tribological studies of nanocomposite films fabricated using spin-assisted layer-by-layer assembly

Abstract

Uniform and smooth composite multilayer films composed of gold nanoparticles and polyelectrolytes ([Au/(PAH-PSS) n PAH] m ) multilayers were fabricated on a silicon substrate using a time-and cost-efficient spin-assisted layer-by-layer (SA-LbL) self-assembly technique. The microstructure and morphology of the multilayer films were characterized by means of transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). The tribological behavior of the composite multilayer films was evaluated using a ball-on-plate tribometer. It was found that the density of the monolayer of gold nanoparticles on the silicon substrate was dependent on the deposition time, but the coverage of the Si substrate by the gold nanoparticle kept almost unchanged at a deposition duration above 30 min. The antiwear life and load-carrying capacity of the [Au/(PAH-PSS) n PAH] m composite film substantially increased with increasing number of the polymer bilayers and gold nanoparticles monolayer, which could be attributed to the robust organic–inorganic nanocomposite structure and PAH and PSS fragments transferred onto the counterpart surface.