Advantages of using MOFs as single-atom catalysts

Metal–organic frameworks (MOFs) are extremely significant crystalline porous materials to develop heterogeneous catalytic systems with unique catalytic potential. Certain MOFs and their derivatives have been explored due to their tailored and hierarchal morphology, electronic properties, and controlled composition for different biological, biomedical, and environmental applications. Herein, we summarize different structural properties of MOFs to appreciate their role as single-atom catalysts (SACs). We categorize different MOFs as SACs: (1) MOFs with functionalized active sites on their framework, (2) encapsulated MOFs with active species, and (3) active sites on MOFs anchored by postsynthetic treatment. We summarize the use of MOFs as heterogeneous catalysts for different organic reactions by following a background introduction of their catalytic relevance. The advantages of MOFs as SACs endow them with various benefits in certain reactions, including tailored porosity, finely tuned active sites, and a microenvironment. Also, we perform a survey for the design of MOFs as heterogeneous catalysts, which was previously thought impossible. Finally the advantages of MOFs as SACs are summarized, and promising future prospects of MOFs are highlighted in conclusion.