Effect of organic linker substituents on properties of metal–organic frameworks: a review†

Abstract

Tuning the properties of solid materials through the directed change of their composition is the most desirable tool for researchers. Varying the electronic structure of metal–organic frameworks by introducing different functional groups into the organic linker is usually regarded as the “Holy Grail” of the synthesis of porous materials with given properties. However, despite having more obvious structure–property relationships in comparison with inorganic porous materials, the chemistry of metal–organic frameworks is more complex, and the presence of a substituent can affect not only the electronic properties but also the structure, stability, numbers of defect sites and coordinatively unsaturated atoms, formation of new adsorption sites, etc. All these changes can influence the field of application of the designed/prepared materials. In the present review, the effect of the substituent nature on a broad range of metal–organic framework characteristics is discussed. The benefits and drawbacks of functionalizing organic linkers in metal–organic frameworks for gas storage and separation as well as catalysis and photocatalysis are also considered.