Superlyophilic Shape Memory Porous Sponge for Smart Liquid Permeation

Recently, smart liquid permeation has aroused much attention. However, existing strategies to achieve such a goal are often based on reversibly controlling hydrophobicity/hydrophilicity on static porous structures, which are unsuitable for oils with low surface tension, and meanwhile they cannot realize tunable permeation flux since the pore sizes are constant. Herein, we report a superlyophilic shape memory porous sponge (SSMS) that can demonstrate tunable pore size from about 28 nm to 900 μm as the material's shape is changed. Based on the controllability in pore size, not only ON/OFF penetration but also precisely tunable permeation flux can be obtained for both water and oil. Furthermore, by using the SSMS, an application in accurate release of small-molecule rhodamine B was also demonstrated. This work reports a material with tunable pore size for controllable liquid permeation, which provides some ideas for designing smart superwetting permeation materials.