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Abstract Asymmetric hydrogenation, a seminal strategy for the synthesis of chiral molecules, remains largely unmet in terms of activation by non‐metal sites of heterogeneous catalysts. Herein, as demonstrated by combined computational and experimental studies, we present a general strategy for integrating rationally designed molecular chiral frustrated Lewis pair (CFLP) with porous metal–organic framework (MOF) to construct the catalyst CFLP@MOF that can efficiently promote the asymmetric hydrogenation in a heterogeneous manner, which for the first time extends the concept of chiral frustrated Lewis pair from homogeneous system to heterogeneous catalysis. Significantly, the developed CFLP@MOF, inherits the merits of both homogeneous and heterogeneous catalysts, with high activity/enantio‐selectivity and excellent recyclability/regenerability. Our work not only advances CFLP@MOF as a new platform for heterogeneous asymmetric hydrogenation, but also opens a new avenue for the design and preparation of advanced catalysts for asymmetric catalysis. 

Abstract The structural advantages of metal‐organic frameworks (MOFs) can facilitate wide applications in the field of catalysis, including oxidation, hydrogenation, acetalization, transesterification, catalytic cracking, and so on. The efficiency of catalysis is closely related to the synergy between active center, auxiliary center, and microenvironment. Researchers can customize MOFs according to the needs of catalytic reactions, and many strategies were established for boosting catalytic performance. In this review, we aim to summarize and illustrate recent progress in the nanospace engineering of MOFs. Generally, MOFs were engineered mainly from the following aspects: 1) Regulation of pore size, including micropores, mesopores, and macropores. 2) Engineering of encapsulated active species, such as metal nanoparticles, quantum dots, polyoxometalates, enzymes, etc. 3) Engineering of MOFs morphology from zero dimension to three‐dimension. 4) Controllable integration of MOFs with multi‐strategies. 5) Construction of multivariate MOFs via introducing multiple or mixed organic functional groups into the existing framework. Besides, for further low cost and practical applications, challenges for MOFs as green and sustainable catalysts are also discussed. 

Abstract The capture of the xenon and krypton from nuclear reprocessing off‐gas is essential to the treatment of radioactive waste. Although various porous materials have been employed to capture Xe and Kr, the development of high‐performance adsorbents capable of trapping Xe/Kr at very low partial pressure as in the nuclear reprocessing off‐gas conditions remains challenging. Herein, we report a self‐adjusting metal‐organic framework based on multiple weak binding interactions to capture trace Xe and Kr from the nuclear reprocessing off‐gas. The self‐adjusting behavior of ATC‐Cu and its mechanism have been visualized by the in‐situ single‐crystal X‐ray diffraction studies and theoretical calculations. The self‐adjusting behavior endows ATC‐Cu unprecedented uptake capacities of 2.65 and 0.52 mmol g⁻¹for Xe and Kr respectively at 0.1 bar and 298 K, as well as the record Xe capture capability from the nuclear reprocessing off‐gas. Our work not only provides a benchmark Xe adsorbent but proposes a new route to construct smart materials for efficient separations. 

Abstract Titanium metal–organic frameworks (Ti‐MOFs), as an appealing type of artificial photocatalyst, have shown great potential in the field of solar energy conversion due to their well‐studied photoredox activity (similar to TiO₂) and good optical responsiveness of linkers, which serve as the antenna to absorb visible‐light. Although much effort has been dedicated to developing Ti‐MOFs with high photocatalytic activity, their solar energy conversion performances are still poor. Herein, we have implemented a covalent‐integration strategy to construct a series of multivariate Ti‐MOF/COF hybrid materials PdTCPP⊂PCN‐415(NH₂)/TpPa (composites 1, 2, and 3), featuring excellent visible‐light utilization, a suitable band gap, and high surface area for photocatalytic H₂production. Notably, the resulting composites demonstrated remarkably enhanced visible‐light‐driven photocatalytic H₂evolution performance, especially for the composite 2 with a maximum H₂evolution rate of 13.98 mmol g⁻¹ h⁻¹(turnover frequency (TOF)=227 h⁻¹), which is much higher than that of PdTCPP⊂PCN‐415(NH₂) (0.21 mmol g⁻¹ h⁻¹) and TpPa (6.51 mmol g⁻¹ h⁻¹). Our work thereby suggests a new approach to highly efficient photocatalysts for H₂evolution and beyond. 

Hybrid organic–inorganic formate perovskites, AB(HCOO)3, are a large family of compounds that exhibit a variety of phase transitions and diverse properties, such as (anti)ferroelectricity, ferroelasticity, (anti)ferromagnetism, and multiferroism. While many properties of these materials have already been characterized, we are not aware of any study that focuses on the comprehensive property assessment of a large number of formate perovskites. A comparison of the properties of materials within the family is challenging due to systematic errors attributed to different techniques or the lack of data. For example, complete piezoelectric, dielectric, and elastic tensors are not available. In this work, we utilize first-principles density functional theory based simulations to overcome these challenges and to report structural, mechanical, dielectric, piezoelectric, and ferroelectric properties of 29 formate perovskites. We find that these materials exhibit elastic stiffness in the range 0.5–127.0 GPa; highly anisotropic linear compressibility, including zero and even negative values; dielectric constants in the range 0.1–102.1; highly anisotropic piezoelectric response with the longitudinal values in the range 1.18–21.12 pC/N; and spontaneous polarizations in the range 0.2–7.8 μC/cm2. Furthermore, we propose and computationally characterize a few formate perovskites that have not been reported yet.