In Situ crystallization to zinc aluminate films with controlled surface microstructure and anticorrosion performance

Spinel‐type zinc aluminate (ZnAl 2 O 4 ) thin films with controlled surface microstructure on aluminum substrates were fabricated via a facile and effective in situ crystallization method without using any templates or surfactants. The surface microstructure of ZnAl 2 O 4 films could be significantly controlled by varying the experimental conditions including concentration of reactants, crystallization temperature, and crystallization time. After surface modification, the specific topography of ZnAl 2 O 4 films was beneficial to obtain surface hydrophobic or superhydrophobic properties. More importantly, compared to nanoparticle‐ and nanosword‐assembled ZnAl 2 O 4 films, nanorod‐assembled ZnAl 2 O 4 film provided a more effective barrier to aggressive species for aluminum substrates in a wide range of pH values; very low corrosion current density of the order of ∼10 −19 A cm −12 could be achieved. A new contribution to the development of advanced coating system with ZnAl 2 O 4 film materials that can be used in practical application for corrosion protection of aluminum materials is provided. © 2011 American Institute of Chemical Engineers AIChE J, 2012