The invention discloses a
sol-
gel method for preparing micro / nano
titanium dioxide and lyophobic film thereof on
metal surfaces, which includes the following steps of (a) pretreating
metal substrates; (b) preparing micro / nano TiO2 films on surfaces of the
metal substrates which are pretreated; and (c) preparing (heptadecafluoro-1,1,2,2-tetradecyl) triisopropoxysilane-
silicon dioxide lyophobic films on the micro / nano TiO2 films on the surfaces of the metal substrates. The
sol-
gel method has the advantages of high
operability, simplicity in
processing and equipment and easiness in industrialization. Besides, the
titanium dioxide films are used as transitional
layers so that
corrosion of acid
sol to the metal substrates during the process of directly
coating the
silane lyophobic films is avoided, wettability to
silane sol is enhanced, and uniform and compact lyophobic films are prepared finally. Meanwhile, defects such as
cracking and the like can be reduced by means of multiple
coating processes,
corrosion resistance performance of the films is improved, surface free energy of the films is decreased by lyophobic treatment, and
dirt settled on the films is reduced.