Self-assembly and tribological properties of a novel organic–inorganic nanocomposite film on silicon using polydopamine as the adhesion layer

Abstract

Utilizing the strong coordination interactions between phenolic hydroxyls of polydopamine (Pdop) and silver oxide nanoparticles (Ag₂O NPs), Ag₂O NPs were successfully assembled on a dual-layer film composed of a polydopamine outer layer and 3-aminopropyltriethoxy silane (APS) sub-layer, on silicon (Si) substrate. The morphologies, structures and chemical compositions of Ag₂O NPs and the tri-layer film were confirmed by various instruments, including ultraviolet absorption spectrum (UV), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). Furthermore, the micro adhesion forces and macro tribological performances were evaluated using AFM and UMT-2M tribometer (CETR), respectively. The results indicated that the tri-layer film displays favourable friction reduction and wear resistance ability. Hence, this renders the self-assembly attractive for constructing the multilayer-structure films with favourable tribological performances for nano/microelectromechanical systems (NEMS/MEMS).