Influence of cyclic organosilicon precursors on the corrosion of aluminium coated sheet by atmospheric pressure dielectric barrier discharge

Atmospheric pressure dielectric barrier discharge depositions on aluminium of octamethylcyclotetrasiloxane and decamethylcyclopentasiloxane were investigated. Scanning Electron Microscopy and Transmission Electron Microscopy revealed the formation of dense and defect free layers while Fourier Transform Infrared Spectroscopy and X-ray Photoelectron Spectroscopy analyses indicated the formation of highly cross-linked siloxane layers. The corrosion protection afforded by such films was investigated by electrochemical techniques and relationships between the deposition parameters, film chemistry and electrochemical properties of these films are reported. The corrosion performances of films grown from the two cyclic siloxane precursors were shown to be significantly higher than the ones achieved by the films grown from hexamethyldisiloxane in previous work.