Defects in Metal–Organic Frameworks: Challenge or Opportunity?

Metal-organic framework (MOF) materials are nanoporous materials whose crystalline character has made them attractive targets for synthesis of new materials and potential use in a diverse set of applications. The vast majority of studies of MOFs envision these materials as having ideal crystal structures. This Perspective gives an overview of the current understanding of defects in MOFs. Compared to related materials such as zeolites, the ability to detect and control defects in MOFs is nascent. Nevertheless, it is likely that defects will play a vital role in a number of contexts where MOFs are of widespread interest, so advancing our understanding of these structural features will be important in coming years. Potential origins of point defects, plane defects, and surface defects are discussed. The difficulty of defect detection in metal-organic frameworks is discussed and useful paths for future work are provided.