A versatile cost-effective and one step process to engineer ZnO superhydrophobic surfaces on Al substrate

Abstract

Multifunctional superhydrophobic surfaces based on photocatalytic material, ZnO have generated significant research interest from both fundamental and potential applications. Superhydrophobic ZnO surfaces are usually made in multi steps by creating rough surface and subsequent hydrophobization by low-surface-energy materials. Herein, a simple and one step chemical bath deposition has been developed to prepare superhydrophobic ZnO surfaces on aluminum substrate. The aluminum surfaces covered with randomly distributed ZnO particles can not only present multiscale surface roughness, but also readily coordinate with fatty acid, leading to special wettability. The contact angle of the resulting superhydrophobic surface reaches up to 165 ± 2° and contact angle hysteresis of 4°. The contact angle and contact angle hysteresis variation as a function of particle size has been discussed systematically based on surface morphology.