Eur. Phys. J. E (2013) 36: 59
https://doi.org/10.1140/epje/i2013-13059-2

Regular Article

Tuning the wettability of an aluminum surface via a chemically deposited fractal dendrite structure

¹ Key Laboratory of Space Applied Physics and Chemistry of Ministry of Education, School of Science, Northwestern Polytechnical University, 710129, Xi’an, China
² School of Physics and Astronomy, University of Edinburgh, Mayfield Road, EH9 3JZ, Edinburgh, UK

^* e-mail: dyzang@nwpu.edu.cn

Received: 6 November 2012
Accepted: 23 May 2013
Published online: 20 June 2013

Abstract

We have developed a straightforward method to tune the wettability of an aluminum substrate within a contact angle (CA) range from 2^° to 170^° by chemical deposition in CuCl₂ solution and fluoroalkylsilane (FAS) modification. The CA of the as-deposited surface decreases with deposition time due to the growth of fractal copper dendrites, which enhance the surface roughness significantly. After subsequent modification with FAS, a superhydrophobic surface with CA 170^° and sliding angle less than 5^° has been obtained. With the increase of CA, the maximum spreading of water droplets is reduced. A bouncing behavior is observed for droplets impinging on the superhydrophobic substrate, suggesting its potential application as a self-cleaning surface.