CuO/Cu based superhydrophobic and self-cleaning surfaces

CuO/Cu based superhydrophobic surfaces with ordered micro/nanostructures have been prepared via a solution immersion process combining with photolithography and argon ion beam etching. CuO nanoneedles grow only inside microholes on copper substrate due to delaying effect of both residual photoresist and carbon layer produced during Ar etching. The hierarchical structures and surfaces show a water contact angle of 152 degrees, a contact angle hysteresis of 3 degrees, and a low water adhesion force of 15 mu N, indicating a good superhydrophobicity. The obtained surfaces also keep itself clean from carbon black, chalk dust and water, enabling a great potential in self-cleaning and anti-fouling applications. (C) 2016 Elsevier Ltd. All rights reserved.