Loading capacity of a self-assembled superhydrophobic boat array fabricated via electrochemical method

The fabrication of superhydrophobic surfaces depends on surface microstructures and surface chemistry. In this Letter, an electrochemical method was developed to fabricate superhydrophobic surfaces, micro/nanometre-scale rough structures were created via electrochemical etching and the surface energy was reduced by the modification of fluoroalkylsilane. Superhydrophobic hexagonal aluminium boats were fabricated via the proposed electrochemical method. These boats formed an array through self-assembly and showed a large loading capacity. In this array, the `Cheerios effect` was adopted to improve the buoyant force of the floaters. The accumulation of `Cheerios effect` can be reinforced with the increase of total face width per unit area or the contact angles. These results indicate that the micro/nanometre-scale rough structures can contribute to the buoyancy of the floaters, and the accumulation of dominant forces on very small scales can have a remarkable effect on a large scale. These findings can be used to improve the loading capacity of the large-scale floaters.