Fabrication of sustainable hydrophobic and oleophilic pseudo-ordered macroporous Fe-Cu films with tunable composition and pore size via electrodeposition through colloidal templates

In this work, sustainable hydrophobic and oleophilic macroporous Fe-Cu films are fabricated using a straightforward, inexpensive and environmentally friendly two-step procedure which combines electrodeposition with the colloidal lithography technique. Elemental, morphological and structural characterization of the resulting pseudo-ordered meshes is carried out and wettability is assessed using contact angle measurements with respect to two distinct film compositions (3 at.% Fe vs 75-85 at.% Fe) and three different pore diameters (namely, 200 nm, 350 nm and 500 nm). Water contact angles are measured to be in the range of approximately 109.0-155.1 degrees (without any post-surface functionalization) and a low contact angle hysteresis is observed in the superhydrophobic samples. The increase in the hydrophobic character of the films correlates well with an increase in surface roughness, whereas differences in composition play a minor role. For the superhydrophobic Fe-rich macroporous film, water-oil separation capability and recyclability are also demonstrated while the pore size is favorable for effective water-oil mixture and emulsion separation. The results shown here demonstrate that sustainable and affordable materials processed in a simple and cheap manner can be an asset for the removal of water-immiscible organic compounds from aqueous environments. (C) 2018 Elsevier Ltd. All rights reserved.