Mechanical property and corrosion resistance of zirconia/polydopamine nanocomposite multilayer films fabricated via a novel non-electrostatic layer-by-layer assembly technique

摘要

Zirconia/polydopamine (ZrO_2/PDA) nanocomposite multilayer films were constructed on Si substrate via a novel nonelectrostatic layer-by-layer (NELBL) assembly technique. The building block of this technique is the newly reported dopamine molecule, which can be attached to almost all material surfaces and undergo oxidation-polymerization to form PDA layers; more importantly, the outer hydroxyl groups of the PDA layer can chelated with certain inorganic oxide nanoparticles to generate oxide films. Thus, ZrO _2/PDA nanocomposite multilayer films were fabricated by sequential NELBL deposition of PDA and ZrO_2 nanoparticles. The formation of the ZrO_2/PDA nanocomposite multilayer films was monitored by the water contact angle (WCA) and ellipsometric thickness measurements, while the microstructure of the fabricated films was analyzed by means of atomic force microscope (AFM), field emission scanning electron microscope (FESEM), X-ray photoelectron spectrum (XPS), and X-ray diffraction (XRD) analysis. The mechanical and anticorrosion behaviors of the annealed ZrO_2/PDA nanocomposite multilayers were found to be greatly enhanced as compared with that of the annealed homogeneous ZrO_2 film. The better mechanical and anticorrosion behaviors of the annealed ZrO_2/PDA nanocomposite multilayers than the annealed homogeneous ZrO_2 film may be closely related to their special microstructure. Namely, the organic-inorganic hybrid microstructure of the annealed ZrO_2/PDA nanocomposite multilayers may largely account for the increased nanohardness and corrosion resistance.