Inherent superhydrophobicity of Sn/SnO_x films prepared by surface self-passivation of electrodeposited porous dendritic Sn

摘要

Superhydrophobic Sn/SnO_x (x= 1 and 2) films were facilely fabricated by surface self-passivation of three-dimensional (3D) hierarchical porous dendritic Sn while exposed to the air. The porous dendritic Sn was obtained rapidly by electrodeposition accompanying release of hydrogen bubbles. Influence of electrodeposition parameters on the surface morphology and wettabillity has been investigated in detail, including deposition potentials, deposition times and electrolyte concentrations. The maximum contact angle reached to 165 on the porous dendritic Sn/SnO_x film electrodeposited in a solution of 60 mM SnCl_2 and 1.5 M H_2SO_4 under -1.7 V for 20 s. Both the hierarchical micro-nanostructures and the spontaneously formed ultrathin surface passivation layer of Sn oxides endow the prepared Sn/SnO_x surface with excellent inherent superhydrophobicity without further surface modification.