Elaboration and characterization of a multifunctional silane/ZnO hybrid nanocomposite coating

The present study aims at investigating the elaboration of a ZnO/sol-gel nanocomposite coating, which can provide a number of properties such as UV-absorption, mechanical and barrier effects, etc. depending on targeted applications. The sol-gel coating formulation is an inorganic-organic hybrid based on tetraethoxysilane (TEOS) and glycidyloxypropyltrimethoxysilane (GPTMS). In order to ensure good dispersion in the sol-gel matrix, ZnO nanoparticles were surface-modified with a silane coupling agent. The functionalization was confirmed by Fourier transform infrared (FTIR) and thermogravimetric (TGA) analyses. Field emission gun-scanning electron microscopy (FEG-SEM) characterization of the nanocomposite film reveals a homogeneous distribution and dispersion of the ZnO nanoparticles throughout the film. Glow discharge optical emission spectrometry (GDOES) analysis allows evaluating the thickness of coatings and getting a depth composition profile. Some properties such as UV-absorption and barrier effect are highlighted using a UV-visible spectrometer and electrochemical impedance spectroscopy (EIS), respectively. The effect of ZnO concentration is also presented.