MOF-based nanofibrous membranes for oily wastewater treatment: Preparation, mechanism, applications, and prospects

Metal-organic frameworks (MOFs), as a category of porous materials with micro-nano size, controllable pore size, and designable special wettability, have exhibited a huge potential in the treatment of oily wastewater. However, some issues, such as poor water stability, fragile structure and difficult recycling, have greatly limited the further development and application of MOFs powders. In recent years, MOF-based nanofibrous membranes that combine MOFs with electrospinning have received special attention in oil/water separation due to their excellent separation efficiency, high permeate flux and favorable reusability. Hence, this review briefly introduces the structure and surface wettability of MOFs, and systematically summarizes the synthesis strategies of MOF-based nanofibrous membranes, especially the in-situ growth method. Moreover, the advances in the application of MOF-based nanofibrous membranes in oil/water separation are highlighted, and the separation mechanism is detailedly analyzed. Subsequently, the stability, anti-fouling, reusability and self-cleaning properties of MOFbased nanofibrous membranes are discussed. Finally, we present the problems and challenges of MOF-based nanofibrous membranes, and propose their future development directions.