Metal–Organic Framework‐Based Hybrid Frameworks

Framework materials, such as metal–organic frameworks (MOFs) and covalent organic frameworks (COFs), offer huge potential for applications in many aspects due to their well‐defined topologies, high crystallinity, inherent porosity, and chemical tunability. One advanced concept of further functionalizing the single framework materials is to construct hybrid frameworks (e.g., MOF‐on‐MOF, MOF‐on‐COF, and COF‐on‐MOF). Herein, different MOF‐based hybrid frameworks with complex compositions and well‐designed structures show excellent properties that cannot be achieved by single framework materials. The synthetic approaches of MOF‐based hybrid frameworks and their related applications are summarized. The opportunities and challenges for MOF‐based hybrid frameworks are also discussed.