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Multi‐module design of framework materials with multiple distinct building blocks has attracted much attention because such materials are more amenable to compositional and geometrical tuning and thus offer more opportunities for property optimization. Few examples are known that use environmentally friendly and cost‐effective solvent‐free method to synthesize such materials. Here, we report the use of solvent‐free method (also modulator‐free) to synthesize a series of multi‐module MOFs with high stability and separation property for C2H2/CO2. The synthesis only requires simple mixing of reactants and short reaction time (2 h). Highly porous and stable materials can be made without any post‐synthetic activation. The success of solvent‐free synthesis of multi‐module MOFs reflects the synergy between different modules, resulting in stable pore‐partitioned materials, despite the fact that other competitive crystallization pathways with simpler framework compositions also exist. [ABSTRACT FROM AUTHOR]

A multi‐stage core‐expansion method is proposed here as one component of the integrative binding‐site/extender/core‐expansion (BEC) strategy. The conceptual deconstruction of the partitioning ligand into three editable parts draws our focus onto progressive core expansion and allows the optimization of both acetylene uptake and selectivity. The effectiveness of this strategy is shown through a family of eight cationic pore‐partitioned materials containing three different partitioning ligands and various counter anions. The optimized structure, Co3‐cpt‐tph‐Cl (Hcpt=4‐(p‐carboxyphenyl)‐1,2,4‐triazole, H‐tph=(2,5,8‐tri‐(4‐pyridyl)‐1,3,4,6,7,9‐hexaazaphenalene) with the largest surface area and highest C2H2 uptake capacity (200 cm3/g at 298 K), also exhibits (desirably) the lowest CO2 uptake and hence the highest C2H2/CO2 selectivity. The successful boost in both C2H2 capacity and IAST selectivity allows Co3‐cpt‐tph‐Cl to rank among the best crystalline porous materials, ionic MOFs in particular, for C2H2 uptake and C2H2/CO2 experimental breakthrough separation. [ABSTRACT FROM AUTHOR]

We report here a strategy for making anionic pacs type porous materials by combining pore space partition with charge reallocation. The method uses the first negatively charged pore partition ligand (2,5,8‐tri‐(4‐pyridyl)‐1,3,4,6,7,9‐hexaazaphenalene, H‐tph) that simultaneously enables pore partition and charge reallocation. Over two dozen anionic pacs materials have been made to demonstrate their excellent chemical stability and a high degree of tunability. Notably, Ni3‐bdt‐tph (bdt=1,4‐benzeneditetrazolate) exhibits month‐long water stability, while CoV‐bdt‐tph sets a new benchmark for C2H2 storage capacity under ambient conditions for ionic MOFs. In addition to tunable in‐framework modules, we show feasibility to tune the type and concentration of extra‐framework counter cations and their influence on both stability and capability to separate industrial C3H8/C3H6 and C6H6/C6H12 mixtures. [ABSTRACT FROM AUTHOR]

Metal chalcogenide supertetrahedral clusters (MCSCs) are of significance for developing crystalline porous framework materials and atomically precise cluster chemistry. Early research interest focused on the synthetic and structural chemistry of MCSC-based porous semiconductor materials with different cluster sizes/compositions and their applications in adsorption-based separation and optoelectronics. More recently, focus has shifted to the cluster chemistry of MCSCs to establish atomically precise structure–composition–property relationships, which are critical for regulating the properties and expanding the applications of MCSCs. Importantly, MCSCs are similar to II–VI or I–III–VI semiconductor nanocrystals (also called quantum dots, QDs) but avoid their inherent size polydispersity and structural ambiguity. Thus, discrete MCSCs, especially those that are solution-processable, could provide models for understanding various issues that cannot be easily clarified using QDs. This review covers three decades of efforts on MCSCs, including advancements in MCSC-based open frameworks (reticular chemistry), the precise structure–property relationships of MCSCs (cluster chemistry), and the functionalization and applications of MCSC-based microcrystals. An outlook on remaining problems to be solved and future trends is also presented. [ABSTRACT FROM AUTHOR]

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 Co2V‐pacs MOFs exhibit near or at record high uptake capacities for C2H2, C2H4, C2H6, and CO2 among MOFs. The storage capacity of C2H2 is 234 cm3 g−1 (298 K) and 330 cm3 g−1 (273 K) at 1 atm for CPM‐733‐dps (the Co2V‐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 C2H2 adsorption capacity following multiple adsorption–desorption cycles. [ABSTRACT FROM AUTHOR]

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 Co2V‐pacs MOFs exhibit near or at record high uptake capacities for C2H2, C2H4, C2H6, and CO2 among MOFs. The storage capacity of C2H2 is 234 cm3 g−1 (298 K) and 330 cm3 g−1 (273 K) at 1 atm for CPM‐733‐dps (the Co2V‐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 C2H2 adsorption capacity following multiple adsorption–desorption cycles. [ABSTRACT FROM AUTHOR]

The introduction of a symmetry‐ and size‐matching pore‐partitioning agent in the form of either a molecular ligand, such as 2,4,6‐tri(4‐pyridinyl)‐1,3,5‐triazine (tpt), or a metal‐complex cluster, into the hexagonal channels of MIL‐88/MOF‐235‐type (the acs net) to create pacs‐type (partitioned acs) crystalline porous materials is an effective strategy to develop high‐performance gas adsorbents. We have developed an integrated COF–MOF coassembly strategy as a new method for pore‐space partitioning through the coassembly of [(M3(OH)1−x(O)x(COO)6] MOF‐type and [B3O3(py)3] COF‐type trimers. With this strategy, the coordination‐driven assembly of the acs framework occurred concurrently and synergistically with the COF‐1‐type condensation of pyridine‐4‐boronic acid into a C3‐symmetric trimeric boroxine molecule. The resulting boroxine‐based pacs materials exhibited dramatically enhanced gas‐sorption properties as compared to nonpartitioned acs‐type materials and are among the most efficient NH3‐sorption materials. [ABSTRACT FROM AUTHOR]

Abstract: Homochiral metal–organic frameworks (MOFs) are an important class of chiral solids with potential applications in chiral recognition; however, relatively few are available. Of great importance is the availability of low‐cost, racemization‐resistant, and versatile enantiopure building blocks. Among chiral building blocks, d‐camphoric acid is highly prolific, yet, its trans‐isomer, l‐isocamphoric acid, has remained unknown in the entire field of solid‐state materials. Its rich yet totally untapped synthetic and structural chemistry has now been investigated through the synthesis of a large family of homochiral metal isocamphorates. The first observation of diastereoisomerism in isostructural MOFs is presented. Isocamphorate has a powerful ability to create framework topologies unexpected from common inorganic building blocks, and isocamphoric acid should allow access to hundreds of new homochiral materials. [ABSTRACT FROM AUTHOR]

Abstract: 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. [ABSTRACT FROM AUTHOR]

Abstract: A new strategy for creating homochiral metal–organic frameworks through a fusion of pillaring and templating concepts is demonstrated. This strategy makes use of the synergy among various chemical interactions during self‐assembly processes, and leads to the synthesis of a series of homochiral frameworks. In the presence of only pillar‐to‐pillar π–π interactions, inter‐pillar forces compete against metal–pillar interactions, resulting in mismatch between pillar‐to‐pillar and metal‐to‐metal separations and consequently 2D materials without pillaring. To create 3D materials, a method was developed to use various aromatic molecules, polycyclic aromatic hydrocarbons in particular, as templates to modulate the inter‐pillar interaction and separation, leading to the formation of 3D homochiral frameworks. The use of aromatic molecules, especially hydrocarbons, as structure‐directing agents, represents a new approach in the development of crystalline porous materials. Aromatic templates can be post‐synthetically extracted to yield flexible porous homochiral materials with gate‐opening gas sorption behaviors for both N2 and CO2 at partial pressures tunable by temperature. [ABSTRACT FROM AUTHOR]

Reported here are two 4-connected 3D frameworks based on monomeric lithium nodes, which are synthesized through a mixed ligand route. By combining a negatively charged imidazole ligand and a neutral bis(imidazolyl)methane ligand (or one of its derivatives), neutral frameworks adopting chiral quartz-dual and diamond topologies have been obtained. These materials have low framework density and can reversibly adsorb hydrogen gas. [ABSTRACT FROM AUTHOR]

Special asymmetric crystallization of porous framework materials from achiral precursors under urothermal conditions is successfully achieved by using an enantiopure liquid as a co-solvent and chirality induction agent, which provides a new strategy for the synthesis of homochiral porous materials containing only achiral building blocks. [ABSTRACT FROM AUTHOR]

We report a family of carbon materials (denoted SFZ8C) prepared from templated carbonization of zeolitic imidazolate framework-8 (ZIF-8) in NaCl–ZnCl 2 eutectic salt. The hard-templating effect of the salt is utilized to sustain the framework and maximize the porosity during carbonization. In addition to rich surface nitrogen and oxygen species, SFZ8Cs have large specific surface area. These combined features give rise to excellent adsorption properties for light hydrocarbon gases. SFZ8Cs have both C 2 H 2 /CO 2 selective and C 3 /C 2 selective adsorption, as well as the ability to selectively remove impurities from methane. Particularly noteworthy is the excellent C 3 /C 2 selective adsorption performance by SFZ8C-900. Its propane/ethane selectivity (7.68) is on par with the best value (7.72) reported so far, yet SFZ8C-900 excels in propane uptake capacity. The multifunctional properties together with the ease for the mass production make SFZ8Cs promising for a number of important applications. Multifunctional Selective Adsorption: Using environmentally friendly solvent-free synthesized ZIF-8 as carbon precursors and NaCl–ZnCl 2 eutectic salt as hard template, porous carbon materials with rich nitrogen sites were obtained. They exhibit strong performance for multiple separation processes such as acetylene/carbon dioxide, three-carbon/two-carbon (C 3 /C 2), and impurity/methane. [Display omitted] [ABSTRACT FROM AUTHOR]

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 Co2V‐pacs MOFs exhibit near or at record high uptake capacities for C2H2, C2H4, C2H6, and CO2 among MOFs. The storage capacity of C2H2 is 234 cm3 g−1 (298 K) and 330 cm3 g−1 (273 K) at 1 atm for CPM‐733‐dps (the Co2V‐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 C2H2 adsorption capacity following multiple adsorption–desorption cycles. [ABSTRACT FROM AUTHOR]

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 Co2V‐pacs MOFs exhibit near or at record high uptake capacities for C2H2, C2H4, C2H6, and CO2 among MOFs. The storage capacity of C2H2 is 234 cm3 g−1 (298 K) and 330 cm3 g−1 (273 K) at 1 atm for CPM‐733‐dps (the Co2V‐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 C2H2 adsorption capacity following multiple adsorption–desorption cycles. [ABSTRACT FROM AUTHOR]

Two novel types of lithium clusters,Li4tetramer andLi2dimer, have been created as the building blocks ofMOFs. The assembly of such unprecedented clusters with two types oftricarboxylate ligands leads to two highly open frameworks, one ofwhich exhibits a very high CO2uptake capacity among Li-basedMOFs. The work reveals the interesting and unprecedented structuralchemistry of lithium ions. [ABSTRACT FROM AUTHOR]