Photoresponsive Superhydrophobic Membrane Crosslinked by Bipedal Pillararenes with Patterned Wettability

The facile fabrication of superhydrophobic membrane with patterned and controllable wettability is crucial to the exploitation of precise control of water flow path. Here, an azobenzene-bridged bipedal pillararenes-crosslinked polypseudorotaxane is used to fabricate a superhydrophobic membrane via the combination of electrospraying and breath figure approaches. Regulation of the relative humidity during electrospraying process and the trans - cis isomerization of azobenzene provide the capability to control the water adhesion force of membrane. These rules are applied to engineer the wettability of membrane into various patterns via re-electrospraying or light irradiation with patterned photomask. These efforts demonstrate the potential of polypseudorotaxanes for applications in smart membrane with patterned wettability.