Recently, smart interfacial materials that can reversibly transit between the superhydrophobicity and superhydrophilicity have aroused much attention. However, all present performances happen in air, and to realize such a smart transition in complex environments, such as oil, is still a challenge. Herein, well-desighned sponge-like nanofibrous membrane with switchable transition between the superhydrophobicity and superhydrophilicity in oil are reported. The switching can be observed by alternation of pre-wetting, washing and heating process, and the smart controllability can be ascribed to the cooperative effect between the surface nanostructures and the chemical composition variation. This paper reports a surface with smart water wettability in oil, which could start some fresh ideas for wetting control on interfacial materials.
