This work investigated the adsorption properties of 3-aminopropyltrimethoxysilane on recycled aluminum alloy. The influence of deposition conditions, such as pH and temperature of the sol-gel solution and the deposit's crosslinking temperature, on the coating's protective properties was studied by potentiodynamic polarization and electrochemical impedance spectroscopy. With Fourier Fourier-transformed infra-red spectroscopy and scanning electron microscopy, the quality of the coating was analyzed. The polarization curves performed on the coating deposited at different pH and temperature values showed that a more compact coating was obtained at pH 4–6 with a depositing temperature of  25 °C. The best crosslinking temperatures are between 100 and 140°C. The analysis of the evolution of the protective barrier properties under long-time immersion conditions by electrochemical impedance spectroscopy showed that the coating exhibits good corrosion performance, compared to the bare alloy, at less than one week. DFT/MC simulation approaches were used to investigate the adsorption orientation of APTMS on the aluminum alloy surface in 3.5
% wt. NaCl solution.

sol-gel; organic/inorganic coating; FTI-IR; corrosion; polarization; impedance, DFT