Electrolytic colouring method for preparing robust coloured superhydrophobic surfaces with good corrosion resistance

Achieving diverse colours in superhydrophobic surfaces is of interest in academic research and industrial applications. The current methods used to prepare coloured surfaces tend to be complicated, expensive or difficult to control the coloured areas and tune the colours. The study reports an efficient and low‐cost electrolytic colouring method for the preparation of robust coloured superhydrophobic Al surfaces. The surfaces are firstly electrochemically etched and anodised before electrolytic colouring is performed. Colours of the superhydrophobic surfaces can be easily tuned by adjusting the anodisation time, and the colouring areas can be well controlled with the combination of mask technology. The corrosion behaviour and abrasion resistance of the coloured superhydrophobic surfaces are characterised by polarisation curves and abrasion tests. The results demonstrate that the coloured superhydrophobic surfaces possess excellent corrosion and abrasion resistances, indicating their application potential in industrial fields.