Defect formation in metal-organic frameworks initiated by the crystal growth-rate and effect on catalytic performance

- Defects (nature & amount) are determined by the crystal growth rate of the procedure.
- Identification & quantification of defects via probe gas techniques was demonstrated.
- The defect structures related catalytic performance was demonstrated.
- A new strategy for defect creation in MOFs can be applied to design catalysts.

The defect formation in metal-organic frameworks (MOFs) initiated by the crystal growth-rate of different synthesis procedures affects the structure, morphology and other properties of MOFs such as particle shape, gas adsorption capacity and specifically catalytic performance etc. Although the design of defect structures and the defect structures itself are well known, comparatively little is known regarding defect creation introduced by the synthesis procedure (different from mixed-linker approach, the use of acid modulators, post-synthetic treatment, etc.) and characterization of the resulting naturally occurring abnormalities (defects) in the material. Moreover, high performance of MOFs in various catalytic reactions can be correlated to the higher amount of defect structures because defects can possibly exhibit acid and/or basic properties. While studies of MOF crystallinity confirmed that for a given type of MOF different synthesis methods generate samples of similar crystal structures, their morphologies are often different due to the differences in the crystallization rates associated with these methods.

97