Interpenetrating Janus Membrane for High Rectification Ratio Liquid Unidirectional Penetration.

Anisotropic interfaces with opposite properties provide numerous unusual physical chemical properties that have played irreplaceable roles in broad domains. Here, we rationally designed an anisotropic Janus membrane with opposite wettability and special interpenetrating interface microstructure, which shows a unidirectional liquid penetration "diode" performance. Liquid is allowed to penetrate from lyophobic to lyophilic direction but is blocked in the reverse direction. Although conventional works suggested the liquid unidirectional penetration is driven by anisotropic wettability in heterogeneous interfaces, here, we theoretically and experimentally reveal that special interpenetrating topology plays another important role in liquid unidirectional penetration. This insight gives a general guide to build a series of Janus membranes for liquid unidirectional penetration with high hydraulic pressure rectification ratio. The liquid diode Janus membrane indicates great promise for liquid manipulation, smart separation membranes, functional textiles, and other fields.