Substrate-free water film for liquid directional transportation

Abstract A novel method of dividing water into two-dimensional patterns has been put forward to fabricate a kind of substrate-free water film in this study. The as-prepared superhydrophilic filaments with forceful capillary force were utilized to form a framework that can support and spread water. The water film of different sizes has a stable load-bearing capacity. Only the excessive water is discharged without breaking the water film when reaching the upper limit. Moreover, puncture damage with a smaller diameter can also quickly self-heal. Therefore, the stability makes the water film have a possible application. For example, various of liquid can slip at a low slip angle along their own water film that can be constructed on demand. In addition, some small and certain shape solid membrane can be obtained via this facile method based on the water film. In summary, the fabrication of this water film provides a novel and convenient method for the directional transportation of micro-droplets and the preparation of small membranes.