Recent Development of Advanced Materials with Special Wettability for Selective Oil/Water Separation

TLDR

Oil spills severely damage aquatic environments, prompting research into special wettable materials that use hydrophobic/oleophilic or hydrophilic/oleophobic properties to selectively separate oil and water. This review summarizes recent advances in special wettability materials for selective oil–water separation and outlines future challenges. The review classifies these materials by separation mechanisms—filtration and absorption—and highlights representative studies focusing on wetting properties and innovative design aspects.

Abstract

The increasing number of oil spill accidents have a catastrophic impact on our aquatic environment. Recently, special wettable materials used for the oil/water separation have received significant research attention. Due to their opposing affinities towards water and oil, i.e., hydrophobic and oleophilic, or hydrophilic and oleophobic, such materials can be used to remove only one phase from the oil/water mixture, and simultaneously repel the other phase, thus achieving selective oil/water separation. Moreover, the synergistic effect between the surface chemistry and surface architecture can further promote the superwetting behavior, resulting in the improved separation efficiency. Here, recently developed materials with special wettability for selective oil/water separation are summarized and discussed. These materials can be categorized based on their oil/water separating mechanisms, i.e., filtration and absorption. In each section, representative studies will be highlighted, with emphasis on the materials wetting properties and innovative aspects. Finally, challenges and future research directions in this emerging and promising research field will be briefly described.