Special wettable materials for oil/water separation

TLDR

Oil/water separation is crucial for both scientific research and practical applications such as treating industrial oily wastewater and oil spills, and recent studies have focused on the role of special wettability in this process. This review aims to summarize the design, fabrication, applications, and recent developments of special wettable materials for oil/water separation. The review is organized into three sections—oil‑removing, water‑removing, and smart controllable materials—each detailing representative work, design concepts, fabrication methods, and the influence of special wettability. The review concludes by outlining challenges and future outlook for special wettable materials in oil/water separation.

Abstract

Oil/water separation is an important field, not only for scientific research but also for practical applications aiming to resolve industrial oily wastewater and oil-spill pollution, as well as environmental protection. Recently, research into the role of special wettability for oil/water separation has attracted much attention. In this review we summarize the design, fabrication, applications and recent developments of special wettable materials for oil/water separation. Based on the different types of separation, we organize this review into three parts: "oil-removing" type materials with superhydrophobicity and superoleophilicity (that selectively filter or absorb oil from oil/water mixtures), "water-removing" type materials with superhydrophilicity and superoleophobicity (that selectively separate water from oil/water mixtures), and smart controllable separation materials. In each section, we present in detail the representative work, introduce the design idea, outline their fabrication methods, and discuss the role of special wettability on the separation. Finally, the challenges and outlook for the future of this subject are discussed.