Microstructure, synergistic mechanism and corrosion behavior of tin oxide conversion film modified by chitosan on aluminum alloy surface

In this paper, a chitosan‑tin oxide composite film (CTOF) composed of clusters of micro-flowers was prepared on aluminum alloy to improve corrosion protection in the 0.1 M H 2 SO 4 and 0.001 M NaF acidic solution by the hydrothermal method . The surface morphology of the film was analyzed by scanning electron microscopy (SEM). The structure and ingredient of the film were research by using X-Ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FT-IR). The method we used is very simple, convenient and pollution-free. The film shows good protective efficiency as high as 99.998% in solution of 0.1 M H 2 SO 4 and 0.001 M NaF which indicates that the films can improve corrosion resistance of aluminum alloy under acidic solution.