Effect of the various synthetic parameters on the silica film formation

In this research work, we used one-step sol-gel method to prepare the hydrophobic silica films onglass substrate. Silica alcosols were synthesized by tetraethoxyortosilicat (TEOS) as a precursor,phenyltriethoxysilane (PTES) as a co-precursor, ethanol (EtOH) as a solvent in the presence ofammonium hydroxide as a catalyst. We investigated the influence of the sol-gel reactionparameters, such as catalyst, solvent and water content and their effects on the morphology andhydrophobic properties of silica films. For preparing coating solution with differenthydrophobicity, the molar ratio of TEOS:PTES was kept constant at ۱:۱ and concentration ofammonium hydroxide, solvent and water content were varied. The silica films were characterizedby atomic force microscopy (AFM), field emission scanning electron microscopy (FE-SEM)images, contact angle measurement (CA). The results revealed that by controlling the sol-gelreaction parameters such as NH۴OH, H۲O and EtOH, it would be possible to achieve transparenthydrophobic silica coatings with different hydrophobicity from ۱۰۰º to ۱۲۰º. The FE-SEM imagesshowed that by changing the catalyst concentration, water and alcohol content in the silica alcosol,different size of silica nanoparticles ranging from ۲۴.۳۳ to ۳۴.۲۳ nm were obtained

کلیدواژه ها:

Sol-gel parameter ، PTES ، Hydrophobic surface ، Silica film.