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An ideal adsorbent for separation requires optimizing both storage capacity and selectivity, but maximizing both or achieving a desired balance remain challenging. Herein, a de‐linker strategy is proposed to address this issue for metal–organic frameworks (MOFs). Broadly speaking, the de‐linker idea targets a class of materials that may be viewed as being intermediate between zeolites and MOFs. Its feasibility is shown here by a series of ultra‐microporous MOFs (SNNU‐98‐M, M=Mn, Co, Ni, Zn). SNNU‐98 exhibit high volumetric C2H2 uptake capacity under low and ambient pressures (175.3 cm3 cm−3 @ 0.1 bar, 222.9 cm3 cm−3 @ 1 bar, 298 K), as well as extraordinary selectivity (2405.7 for C2H2/C2H4, 22.7 for C2H2/CO2). Remarkably, SNNU‐98‐Mn can efficiently separate C2H2 from C2H2/CO2 and C2H2/C2H4 mixtures with a benchmark C2H2/C2H4 (1/99) breakthrough time of 2325 min g−1, and produce 99.9999 % C2H4 with a productivity up to 64.6 mmol g−1, surpassing values of reported MOF adsorbents. [ABSTRACT FROM AUTHOR]

We report here a one‐step method for synthesizing multi‐component and in‐situ‐formed homochiral spiroborate‐ester‐based metal‐organic framework CPM‐B1. This unique material successfully integrates COF fragment spiroborate ester within the MOF and simultaneously incorporate homochirality and helicity. In addition, CPM‐B1 is a rare example of framework materials that results from the cooperative assembly of three charge‐complementary cations: +1 (lithium), +2 (cobalt), and +3 (boron). The sophistication of the co‐assembly is further highlighted by the three structural roles of lithium ions. This unique structure contributes to its multi‐functional properties such as ionic conductivity and catalytic activity for oxygen reduction reaction (by CPM‐B1 carbonized material) and provides a new path to develop MOF materials with complex secondary building units and multi‐functional applications. [ABSTRACT FROM AUTHOR]

Author(s): Nanfeng Zheng [1]; Xianhui Bu [2, 3]; Pingyun Feng (corresponding author) [1] Natural porous solids such as zeolites are invariably formed with inorganic cations such as Na[sup.+] and K[sup.+] [...]

Crystalline semiconducting sulfide and selenide zeolite analogs were synthesized that possess four-connected, three-dimensional tetrahedral networks built from tetravalent ([M.sup.4+] = [Ge.sup.4+] or [Sn.sup.4+], where M = meta) and trivalent ([M.sup.3+] = [Ga.sup.3+] or [In.sup.3+]) cations. Microporous materials were obtained in all four combinations of [M.sup.4+] and [M.sup.3+], and some of them were thermally stable up to at least 380°C. These materials exhibit framework topologies with pore size ranging from 12 to 24 tetrahedral atoms, high surface area, high framework charge density and ion exchange capacity, and tunable electronic and optical properties., Microporous materials exemplified by aluminosilicate zeolites have large-scale commercial applications ranging from gas separation to petroleum processing (1). For ~50 years, there has been interest in developing porous materials with [...]

Research has been conducted on the ruthenium salen nitrosyl and ruthenium salophen nitrosyl complexes. The synthesis, characterization and photochemical reactions of these complexes have been investigated and the photochemical applications of the nitric oxide delivery to biological targets are discussed.

Trimethylamine isocyanoborane and its coordination adduct with [Re(CO)4Br]2 were characterized by X-ray crystal and molecular structures. Findings indicated that there is no need to postulate the formation of a dynamic pi-sigma coordinated complex of C4H11BN2 with [Mn(CO)4Br]2 or dynamic exchange between free and metal-coordinated complexes in the rhenium or manganese carbonyl complexes of trimethylamineisocyanoborane.

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]

Research was conducted to examine the hydrothermal synthesis and structural characterization of zeolite-like structures based on gallium and aluminum germanates. A novel class of germanate zeolite structures were prepared with inorganic cations or organic amines as structure-directing agents. The successful synthesis of several gallo- and aluminogermanate zeolite-like structures represents an important breakthrough in the synthesis of Ge-based 4-connected 3D framework structures.

Helical pores in inorganic materials rarely occur, but the increasing demand for enantiomerically pure chemicals has led to research into the preparation of heterogeneous chiral catalysts that can combined shape selectivity with enantioselectivity. A group of zeolite-type materials (UCSB-7) that have two independent sets of three-dimensional crosslinked helical pores, is reported. The UCSB-7 framework was synthesized, and the helical-ribbon motif identified could be used more widely in the development of useful chiral solid-state structures.

Zeolite analogues that contain transition metals are useful in industrial processes such as catalysis and gas separation. Several new zeolite structural analogues have been synthesized based on cobalt phosphate. The approach used to make zeolite analogues, could be applied to systems with diverse structural types and chemical constructions, and also be used to make structural analogues of other silicate structures.