Predesign and Systematic Synthesis of 11 Highly Porous Coordination Polymers with Unprecedented Topology

Anion Regulates Topological Porous Coordination Polymers into the Acetylene Trap

The development of efficient porous absorbents with high uptake and selectivity remains a great challenge, especially for the recovery of acetylene (C₂H₂) from its carbon dioxide (CO₂)-containing mixtures. Here, we propose and report an anion-planting strategy for regulating the scu topological porous coordination polymers (PCPs) into the C₂H₂ trap. The three electronegative anions SiF₆^2-, TiF₆^2-, and ZrF₆^2-, in addition to the ligand of 3,5-di(1H-imidazol-1-yl)benzoic acid (HL) and Cu²⁺ ion, were employed to construct highly porous PCPs (NTU-60, NTU-61, and NTU-62) with varied window aperture. Especially, due to a matching distance (d_F-F) of 5.7 Å along the c-axis, the limited space that can be assigned as a single C₂H₂ trap enables NTU-61 to show optimal ability for C₂H₂ (van der Waals (vdW) parameters of the two H atoms: ∼5.72 Å) recognition, validated by Grand Canonical Monte Carlo (GCMC) calculations and Raman spectra. These characteristics allow the NTU-series to show higher C₂H₂ uptake, as well as excellent C₂H₂/CO₂ separation performance under dynamic conditions. The molecular insight and strategy here not only permit balanced adsorption and separation in a single domain but also exhibit an opportunity to develop advanced adsorbents in nearly all frameworks with lattice or coordinated ions, which may act as the platforms for various selective guest trappings with on-demand time and/or spatial resolution.

The synthesis of metal-organic frameworks with template strategies

The synthesis of metal-organic frameworks (MOFs) with a template strategy is still fascinating and has received considerable attention from structural chemists. In this review, developments in tuning MOF hosts or pore structures with a template strategy in the past decades are summarized. By adding templates into MOF precursors, novel template@MOF materials can always be obtained, which cannot be accessed by traditional synthesis procedures. Template@MOF materials can be structurally characterized to help understand the interactions between host frameworks and guest templates. On the other hand, changing the species or amount of template may lead to a pore structure change that can be used as a molecular container to load functional guest molecules with matching sizes for specific applications. It is hoped that this review will provide future researchers with new insight into the design and synthesis of MOF materials by applying suitable templates.

Mechanical Synthesis of COF Nanosheet Cluster and Its Mixed Matrix Membrane for Efficient CO2 Removal

Covalent organic framework (COF) membranes used for selective removal of CO₂ were believed as an efficient and low-cost solution to energy and environmental sustainability. In this study, the amide modified COF nanosheet cluster with a 2D structure was facilely prepared through solid reaction, exhibiting good adsorption-based CO₂ selectivity (223 at 273 K and 90 at 298 K) toward N₂. Remarkably, the mixed matrix membrane (MMM) that consists of a lesser amount of COF filler (1 wt %) shows promising CO₂/N₂ gas selectivity (∼64). In addition, the competitive adsorption prompts the selectivity to ∼72 under an equimolar CO₂/N₂ mixture, which surpasses the values of all reported COF membranes. It is worth to note that the binary gas separation is stable during 120 h.

Rational Design and Functionalization of a Zinc Metal-Organic Framework for Highly Selective Detection of 2,4,6-Trinitrophenol

To develop potential metal-organic frameworks (MOFs) for 2,4,6-trinitrophenol (TNP) detection, an amino-functionalized Zn-MOF, [NH₂(CH₃)₂][Zn₄O(bpt)₂(bdc-NH₂)_0.5]·5DMF (where H₃bpt = biphenyl-3,4',5-tricarboxylate, H₂bdc-NH₂ = 2-aminoterephthalic acid, and DMF = N,N-dimethylformamide), has been designed theoretically and synthesized experimentally. Its structure is composed of Zn₄O(CO₂)₇ secondary building units linked by mixed ligands, exhibiting a three-dimensional framework. Fluorescence exploration revealed that the amino-functionalized Zn-MOF shows high selectivity and sensitivity for TNP, which agrees well with the predictions of theoretical simulations. This work provides a suitable means to develop new potential MOFs for TNP detection performance with a combination of experimental and theoretical perspectives.

Design and synthesis of luminescent porous coordination polymers for chromaticity modulation, sensing of nitrobenzene and iodine encapsulation

A family of porous coordination polymers constructed from C_2v symmetry ligands with increased conjugation moieties was systematically designed and prepared, which is highly promising for chromaticity modulation, sensing of nitrobenzene, and I₂ encapsulation.

New luminescent porous coordination polymers with an acylamide-decorated linker for anion recognition and reversible I2 accommodation

A new series of porous coordination polymers with significant 1D channels and open and open acylamide groups demonstrate good potential for selectively probing Cu²⁺ ions. Meanwhile, they show rapid and reversible I₂ accommodation properties.

Two solvent-dependent porous coordination polymers with –OH decorated ligands: unusual non-crystallographic net and fsh topology

The variable architectures of two new porous coordination polymers, controlled by solvent system, exhibit a structural progression from an unusual non-crystallographic net to a (4,6)-connected framework with fsh topology.