Compositional Complexity of Metal-Organic Frameworks with Programmable Spatial Arrangement of Multi-Metallic Components

The components and structures of metal-organic frameworks (MOFs) are critical two factors that influence their properties and prospective applications. Moreover, the construction of complex MOFs integrating multiple components holds promise to achieve MOFs with unique properties. However, constructing complex MOFs with an intended 3D spatial arrangement of the multiple components remains underdeveloped. Herein, a systematic approach is reported for designing and constructing complex MOFs featuring multi-metallic components with programmed 3D spatial distributions. Syringe pumps with programmed injection rates are employed to feed the intended amounts of multi-metallic components into a reactor at specific time points. By controlling the quantities of components present in the reactor, their incorporation within MOFs is carefully managed, eventually achieving the intended spatial arrangement of multi-metallic components within MOFs. This approach is successfully applied to constructing numerous bimetallic and trimetallic zeolitic imidazolate frameworks with programmed spatial distributions of Zn²⁺, Co²⁺, Cu²⁺, and/or Ni²⁺, with varied combinations, quantities, sequences, and numbers. This method is also suitable for fabricating the bimetallic MIL-88B, proving its applicability to many MOFs. Using this method, precise control over multiple components with intended and complex spatial distributions can be attained, enabling the construction of special MOFs with tailored properties and functions.