Photoelectric cooperative patterning of liquid permeation on the micro/nano hierarchically structured mesh film with low adhesion

Stimuli-responsive surface wettability has been intensively studied, especially wettability controlled by photoelectric cooperation, which appears to be a trend for more effective surface wetting. In this field, the patterning of controllable surface wettability is still a challenge in the application of liquid-printing techniques because of the high adhesion and high responsive voltage, as well as low mechanical strength, of the substrate. Herein, we have demonstrated the patterning of liquid permeation controlled by photoelectric cooperative wetting on the micro/nano hierarchically structured ZnO mesh film. The special micro/nano hierarchically structured ZnO mesh is beneficial for lowering adhesion force on the mesh surface than those of the TiO₂/AAO nanopore array films previously reported for the discontinuous tri-phase contact line, in addition to precisely controlled microscale liquid movement with considerably lower threshold voltage for the hierarchical structure. Moreover, the stainless-steel mesh with different pore sizes as a substrate behaves with higher mechanical strength and lower cost, compared with the anodized Ti mesh. Thus, this work is promising for accelerating the development of patterned liquid permeation and extending the application of micro/nanofluidic system and micronanoelectronic technology.