MOFs with hierarchical nanostructures towards future functional polymers

Metal-organic frameworks (MOFs) are a novel class of multidimensional nanomaterials with high specific surface area, porosity, and ease of chemical functionalization that show tremendous potential for various applications. Furthermore, the structure, function, and composition of MOFs can all be changed to increase their effectiveness in certain applications. By choosing appropriate functional substances to modify it, the structure of MOFs can be readily changed. This allows for the synthesis of MOFs with hierarchical nanostructures containing a variety of functional components to fit specific requirements. At present, hierarchical MOFs as functional fillers of polymers have attracted great interest from researchers. This work will systematically discuss the synthesis of MOFs with various hierarchical nanostructure features (such as yolk@double-shelled nanostructure, yolk@shell nanostructure, core@shell nanostructure, and hollow nanostructure). The potential uses of MOF-derived materials in polymer, particularly in the areas of gas adsorption/separation, microwave absorption, sewage treatment, electricity, and flame retardant, will be discussed. At the same time, we highlight the connection between their distinct hierarchical nanostructures and particular characteristics to elucidate their potential mechanisms. Lastly, some recommendations are made about the future research and development of MOFs with different hierarchical nanostructures.