Hydrogels: a review on their versatile applications for efficient and stable oil-water separation

Oil spills and the environmental pollution accidents caused by them have gradually become a serious problem that human industrial and commercial development must face. As a highly promising material for modification, hydrogels have attracted considerable attention in the field of oil-water separation applications. In this review, we first classify the synthesis principles, material structures and raw material differences of hydrogel materials. Then, the properties of hydrogels are discussed in depth, highlighting the special properties that can be brought about by different modification methods, as well as the properties required for different types of oil-water separation materials. Then, in relation to the problem of oil-water separation, the main applications of hydrogels in oil-water separation direction and the characteristics of composite hydrogels are taken as examples to show the research potential of hydrogels in oil-water separation. Finally, the advantages and disadvantages of hydrogels are analyzed, the challenges associated with their use in oil-water separation are addressed, and their future development in the direction of oil-water separation is predicted.