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Metal trimers [M 3 (O/OH)](OOCR) 6 are among the most important structural building blocks. From these trimers, a great success has been achieved in the design of 6- or 9-connected framework materials with various topological features and outstanding gas-sorption properties. In comparison, 8-connected trimer-based metal-organic frameworks (MOFs) are rare. Given multiple competitive pathways for the formation of 6- or 9-connected frameworks, it remains challenging to identify synthetic or structural parameters that can be used to direct the self-assembly process toward trimer-based 8-connected materials. Here, a viable strategy called angle bending modulation is revealed for creating a prototypical MOF type based on 8-connected M 3 (OH)(OOCR) 5 (Py-R) 3 trimers (M = Zn, Co, Fe). As a proof of concept, six members in this family are synthesized using three types of ligands (CPM-80, -81, and -82). These materials do not possess open-metal sites and show excellent uptake capacity for various hydrocarbon gas molecules and inverse C 2 H 6 /C 2 H 4 selectivity. CPM-81-Co, made from 2,5-furandicarboxylate and isonicotinate, features selectivity of 1.80 with high uptake capacity for ethane (123 cm 3 g -1 ) and ethylene (113 cm 3 g -1 ) at 298 K and 1 bar., (© 2020 Wiley-VCH GmbH.)

Introduction of pore partition agents into hexagonal channels of MIL-88 type (acs topology) endows materials with high tunability in gas sorption. Here, we report a strategy to partition acs framework into pacs (partitioned acs) crystalline porous materials (CPM). This strategy is based on insertion of in situ synthesized 4,4'-dipyridylsulfide (dps) ligands. One third of open metal sites in the acs net are retained in pacs MOFs; two thirds are used for pore-space partition. The Co 2 V-pacs MOFs exhibit near or at record high uptake capacities for C 2 H 2 , C 2 H 4 , C 2 H 6 , and CO 2 among MOFs. The storage capacity of C 2 H 2 is 234 cm 3  g -1 (298 K) and 330 cm 3  g -1 (273 K) at 1 atm for CPM-733-dps (the Co 2 V-BDC form, BDC=1,4-benzenedicarboxylate). These high uptake capacities are accomplished with low heat of adsorption, a feature desirable for low-energy-cost adsorbent regeneration. CPM-733-dps is stable and shows no loss of C 2 H 2 adsorption capacity following multiple adsorption-desorption cycles., (© 2020 Wiley-VCH GmbH.)

The creation of new cluster building blocks, as well as new ligand coordination modes, are among the most effective ways to develop new framework materials. Yet, large and chiral clusters are both difficult to create and relatively few. Here, by studying the competing coordination of different azolates against carboxylate and combined carboxylate/phenolate, it is shown that the impact of azolates in the MOF-74 synthesis system differs dramatically, leading to the synthesis of MOF-74, UTSA-74, and CPM-72 for 2-methylimidazole, 1,2,4-triazole, and 1,2,3-triazole, respectively. The new CPM-72 contains a novel chiral Zn 12 triazolate cluster, which features a trigonal-prismatic Zn 6 core inside an octahedral Zn 6 shell. In contrast with MOF-74 with fully deprotonated and symmetrically bonded 2,5-dihydroxyterephthalic acid (H 4 DOBDC), H 4 DOBDC adopts an unusual nonsymmetric bonding mode in CPM-72 (carboxylate only at one end and carboxylate/phenolate at the other), resulting in a highly porous and intrinsically chiral 3D framework. The nonsymmetric bonding mode by H 4 DOBDC, apparently dictated by the chiral Zn 12 cluster, can be replicated with 2-hydroxyterephthalic acid (H 3 OBDC), leading to the synthesis of porous isoreticular CPM-73., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Zeolite-type chalcogenides are desirable due to their integration between porosity and semiconductivity. CPM-120, with super-sodalite topology (Zeolite Structure Code: RWY), is among the few zeolite-type chalcogenides with permanent porosity, and is the only chalcogenide with a zeolite code. Importantly, the RWY-type has evolved into a platform for studying properties of porous chalcogenides. Yet so far, few studies have been made to probe the effects of synthetic parameters and framework compositions on this platform. Here, we probe the effects of the third metal type (Ga 3+ , In 3+ , Cd 2+ , and Sn 4+ ) on the Zn 2+ /Ge 4+ /S 2- platform. We find that charge-complementary and size-compatible Ga 3+ leads to the synthesis of CPM-120-ZnGaGeS which is the first trimetallic zeolite-type chalcogenide, with improved crystal morphology and reproducibility. We also find that charge-compatible and size-complementary cations (Cd 2+ or Sn 4+ ) can induce an abrupt phase transition from super-sodalite to super-diamond, also with unprecedented trimetallic T2 clusters. For In 3+ , which is dual-complementary (charge and size), a gradual phase transition is observed with increasing In 3+ amount. Furthermore, by controlling the cluster composition, tunable band gaps can be realized. These materials show promising properties such as high CO 2 uptake (4.32 mmol cm -3 , 298 K, 1 bar) and high photocatalytic activity., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In porous materials, metal sites with coordinate solvents offer opportunities for many applications, especially those promoted by host-guest chemistry, but such sites are especially hard to create for Li-based materials, because unlike transition metals, lithium does not usually possess a high-enough coordination number for both framework construction and guest binding. This challenge is addressed by mimicking the functional group ratio and metal-to-ligand charge ratio in MOF-74. A family of rod-packing lithium-organic frameworks (CPM-47, CPM-48, and CPM-49) were obtained. These materials exhibit an extremely high density of guest-binding lithium sites. Also unusual is the homo-helical rod-packing in the CPM series, as compared to the hetero-helical rod packing by helices of opposite handedness in MOF-74. This work demonstrates new chemical and structural possibilities in developing a record-setting high density of guest-binding metal sites in inorganic-organic porous materials., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The development of novel photocatalysts usually centers on features such as band structures, various nano-, micro-, or macro-forms, and composites in efforts to tune their light absorption and charge separation efficiency. In comparison, the selectivity of photocatalysts with respect to features of reactants such as size and charge has received much less attention, in part due to the difficulty in designing semiconducting photocatalysts with uniform pore size. Here, we use crystalline porous chalcogenides as a platform to probe reactant selectivity in photocatalytic processes. The 3-in-1 integration of high surface area, uniform porosity, and favorable band structures in such chalcogenides makes them excellent candidates for efficient and selective photocatalytic processes. We show that their photocatalytic activity and selectivity are closely related to their differing affinity and selectivity for different guest species. In particular, unlike common solid-state photocatalysts with neutral framework, the anionic nature of the porous chalcogenide framework used here endows them with a high degree of selectivity for cationic species in both guest exchange and closely coupled photocatalytic transformation of such guests. Another interesting discovery is the observation of an unusual ion exchange process involving a transient state of over-saturation of exchanged ions, which can be explained by a transition from an initially kinetically controlled process to a subsequent thermodynamically controlled one. This work is part of ongoing efforts to contribute to the development of a new generation of crystalline porous photocatalysts with custom-designed selectivity for various reactants or products., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Metal-organic polyhedra (MOPs) or frameworks (MOFs) based on Cr(3+) are notoriously difficult to synthesize, especially as crystals large enough to be suitable for characterization of the structure or properties. It is now shown that the co-existence of In(3+) and Cr(3+) induces a rapid crystal growth of large single crystals of heterometallic In-Cr-MOPs with the [M8L12] (M=In/Cr, L=dinegative 4,5-imidazole-dicarboxylate) cubane-like structure. With a high concentration of protons from 12 carboxyl groups decorating every edge of the cube and an extensive H-bonded network between cubes and surrounding H2O molecules, the newly synthesized In-Cr-MOPs exhibit an exceptionally high proton conductivity (up to 5.8×10(-2) S cm(-1) at 22.5 °C and 98% relative humidity, single crystal)., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A robust porous metal-organic framework (MOF), [Co(3)(ndc)(HCOO)(3)(μ(3)-OH)(H(2)O)](n) (1) (H(2)ndc=5-(4-pyridyl)-isophthalic acid), was synthesized with pronounced porosity. MOF 1 contained two different types of nanotubular channels, which exhibited a new topology with the Schlafli symbol of {4(2).6(5).8(3)}{4(2).6}. MOF 1 showed high-efficiency for the selective sorption of small molecules, including the energy-correlated gases of H(2), CH(4), and CO(2), and environment-correlated steams of alcohols, acetone, and pyridine. Gas-sorption experiments indicated that MOF 1 exhibited not only a high CO(2)-uptake (25.1 wt % at 273 K/1 bar) but also the impressive selective sorption of CO(2) over N(2) and CH(4). High H(2)-uptake (2.04 wt % at 77 K/1 bar) was also observed. Moreover, systematic studies on the sorption of steams of organic molecules displayed excellent capacity for the sorption of the homologous series of alcohols (C(1)-C(5)), acetone, pyridine, as well as water., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)