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Multivariate metal–organic frameworks (MTV‐MOFs) provide a handle over programming MOF's physicochemical properties for use in functional applications. In this review, the state‐of‐art design features of MTV‐MOFs are summarized, including multivariate functionalities, mixed metals, and post‐synthetic modification, and highlight their resulting fine‐tuned performance in practical applications, such as gas storage, gas separation, water harvesting, luminescence sensing, heterogeneous catalysis, and drug delivery. Furthermore, a vision is provided for future research avenues, in which MTV‐MOFs enable the incorporation of a variety of functionalities, metals, linkers, secondary building units (SBUs), and pore metrics along a specific crystallographic direction with respect to the ordered backbone. Future directions focus on mechanistic and kinetics investigations into the formation of MTV‐MOFs in addition to high‐throughput screening with the aim of automation and artificial intelligence. [ABSTRACT FROM AUTHOR]

Developing porous materials to overcome the trade‐off between adsorption capacity and selectivity for C2H2/CO2 separation remains a challenge. Herein, we report a stable HKUST‐1‐like MOF (ZJU‐50a), featuring large cages decorated with high density of supramolecular binding sites to achieve both high C2H2 storage and selectivity. ZJU‐50a exhibits one of the highest C2H2 storage capacity (192 cm3 g−1) and concurrently high C2H2/CO2 selectivity (12) at 298 K and 1 bar. Single‐crystal X‐ray diffraction studies on gas‐loaded ZJU‐50a crystal unveil that the incorporated supramolecular binding sites can selectively take up C2H2 molecule but not CO2 to result in both high C2H2 storage and selectivity. Breakthrough experiments validated its separation performance for C2H2/CO2 mixtures, providing a high C2H2 recovery capacity of 84.2 L kg−1 with 99.5 % purity. This study suggests a novel strategy of engineering supramolecular binding sites into MOFs to overcome the trade‐off for this separation. [ABSTRACT FROM AUTHOR]

Developing porous materials to overcome the trade-off between adsorption capacity and selectivity for C 2 H 2 /CO 2 separation remains a challenge. Herein, we report a stable HKUST-1-like MOF (ZJU-50a), featuring large cages decorated with high density of supramolecular binding sites to achieve both high C 2 H 2 storage and selectivity. ZJU-50a exhibits one of the highest C 2 H 2 storage capacity (192 cm 3  g -1 ) and concurrently high C 2 H 2 /CO 2 selectivity (12) at 298 K and 1 bar. Single-crystal X-ray diffraction studies on gas-loaded ZJU-50a crystal unveil that the incorporated supramolecular binding sites can selectively take up C 2 H 2 molecule but not CO 2 to result in both high C 2 H 2 storage and selectivity. Breakthrough experiments validated its separation performance for C 2 H 2 /CO 2 mixtures, providing a high C 2 H 2 recovery capacity of 84.2 L kg -1 with 99.5 % purity. This study suggests a novel strategy of engineering supramolecular binding sites into MOFs to overcome the trade-off for this separation., (© 2022 Wiley-VCH GmbH.)

Three-membered rings (3-rings) are an important structural motif in zeolite chemistry, but their formation remains serendipitous in reticular chemistry when designing zeolitic imidazolate frameworks (ZIFs). Herein, we report a design principle for constructing four new ZIFs, termed ZIF-1001 to -1004, from tetrahedral Zn II centers (T), benzotriazolate (bTZ), and different functionalized benzimidazolates (RbIM) that adopt a new zeolite NPO-type topology built from 3-rings. Two factors were critical for this discovery: i) incorporating the bTZ linker within the structures formed 3-rings due to a ∠(T-bTZ-T) angle of 120-130° reminiscent of the ∠(Ge-O-Ge) angle (130°) observed in germanate zeolite-type structures having 3-rings; and ii) RbIM guided the coordination chemistry of bTZ to bind preferentially in an imidazolate-type mode. This series' ability to selectively capture CO 2 from high-humidity flue gas and trap ethane from tail gas during shale gas extraction was demonstrated., (© 2022 Wiley-VCH GmbH.)