2D Metal‐Organic Framework Materials for Membrane‐Based Separation

Metal‐organic framework (MOF) nanosheets are promising membrane building blocks for ultimate and efficient separation because of the diversified structures, ultrathin thickness, and tunable chemical functionalities. Targeting at membrane‐based separation, representative developments of top‐down and bottom‐up methods to produce high‐quality MOF nanosheets are introduced, and the merits and demerits of each method are carefully elucidated. A summary of fabrication approaches of MOF nanosheet‐based membranes is also put forward to establish a comprehension on the relationship between membrane structure and the eventual separation performance. Moreover, classical characterization techniques to get an insight into these 2D materials are addressed. Last but not least, concerns on the challenges and opportunities for these novel membranes are demonstrated in order to provide some guidelines for the development in the future.