A simple immersion approach for fabricating superhydrophobic Mg alloy surfaces

► A simple immersion approach was developed to fabricate superhydrophobic Mg alloy surfaces. ► The approach only needs 10 min to get the roughness required by superhydrophobicity. ► A layer of green film was obtained after immersion in the aqueous CuSO4 solution. ► Superhydrophobicity can be obtained on the surfaces only containing micrometer-scale structures.