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Reticular chemistry and pore engineering have garnered significant advancements in metal–organic frameworks and covalent organic frameworks, leveraging robust metal‐coordination and covalent bonds. However, these achievements remain elusive in hydrogen‐bonded organic frameworks, hindered by their inherent weakness in hydrogen bonding. Herein, we strategically manipulate the porosity of hydrogen‐bonded frameworks through a grafting approach, culminating in the synthesis of two isomorphic HOFs, HOF‐FJU‐99 and HOF‐FJU‐100, with distinct pore environments. Remarkably, HOF‐FJU‐100, with its microporous architecture, not only showcases exceptional stability but also achieves unparalleled separation efficiency and ultrahigh selectivity for C2H2/CO2 mixtures (50/50, v/v) under ambient conditions. Its IAST selectivity value of 201 stands as a benchmark, towering over all previously reported HOFs. The pore of HOF‐FJU‐100 boasts an electrostatic potential highly favourable for C2H2 adsorption, as evidenced by single crystal X‐ray diffraction analysis revealing multiple hydrogen bonding interactions between C2H2 molecules and the framework. In situ gas‐carrier powder X‐ray diffraction analysis underscores the adaptability of pore structure, dynamically adjusting its orientation in response to C2H2, thereby enabling a highly efficient and specific separation of C2H2/CO2 mixtures through specific adsorptive interactions. [ABSTRACT FROM AUTHOR]

Separation of acetylene (C2H2) from carbon dioxide (CO2) or ethylene (C2H4) is industrially important but still challenging so far. Herein, we developed two novel robust metal organic frameworks AlFSIX‐Cu‐TPBDA (ZNU‐8) with znv topology and SIFSIX‐Cu‐TPBDA (ZNU‐9) with wly topology for efficient capture of C2H2 from CO2 and C2H4. Both ZNU‐8 and ZNU‐9 feature multiple anion functionalities and hierarchical porosity. Notably, ZNU‐9 with more anionic binding sites and three distinct cages displays both an extremely large C2H2 capacity (7.94 mmol/g) and a high C2H2/CO2 (10.3) or C2H2/C2H4 (11.6) selectivity. The calculated capacity of C2H2 per anion (4.94 mol/mol at 1 bar) is the highest among all the anion pillared metal organic frameworks. Theoretical calculation indicated that the strong cooperative hydrogen bonds exist between acetylene and the pillared SiF62− anions in the confined cavity, which is further confirmed by in situ IR spectra. The practical separation performance was explicitly demonstrated by dynamic breakthrough experiments with equimolar C2H2/CO2 mixtures and 1/99 C2H2/C2H4 mixtures under various conditions with excellent recyclability and benchmark productivity of pure C2H2 (5.13 mmol/g) or C2H4 (48.57 mmol/g). [ABSTRACT FROM AUTHOR]

Effective C2H2/CO2 separation is regarded as a crucial procedure in the C2H2 industry yet extremely challenging because of their similar physical and chemical properties. Covalent organic frameworks (COFs) have become a promising platform for gas adsorption separation, but they still suffer from unsatisfactory C2H2 adsorption capacity and selectivity. Herein, we report a nanoporous fluorine-functioned COF (TpPa-F) for C2H2/CO2 separation, which was synthesized by a mechanochemical approach with a F-containing precursor (2-fluoro-1,4-benzenediamine). A superior C2H2 adsorption capacity of 117 cm3/g (4.78 mmol/g) and a C2H2/CO2 selectivity of 3.3 at 298 K and 1 bar were achieved, which surpass most of the reported COF adsorbents in the literature. Notably, TpPa-F exhibited an extraordinary thermal stability of up to around 673 K and showed chemical robustness in organic or acidic/basic solutions. Theoretical calculations reveal the hydrogen bond interaction of CC–H···F, which contributes to the high C2H2 uptake and separation selectivity. This work provides a promising strategy of fluorine functionalization for enhancing the ability to recognize and separate small gas molecules in a large channel. [ABSTRACT FROM AUTHOR]

The charged metal–organic framework (MOF) (anionic and cationic MOF) material plays an important role in gas adsorption and separation and ecological environment management. Herein, we reported a partially charged Mg-based MOF (FJU-129) with dimethylamine counterions, which can efficiently separate C2H2 from CO2 and rapidly adsorb the cationic dye methylene blue (MB). FJU-129a showed a high uptake capacity of up to 133.8 cm3/g for C2H2 at 273 K, 1 bar, and low isosteric heat of adsorption of C2H2 (24.78 kJ/mol). The C2H2/CO2 separation is validated by a dynamic breakthrough experiment at 296 K, 1.5 bar, and the Grand Canonical Monte Carlo simulation revealed that the partially remaining charge on the magnesium sites has an electrostatic force on the −CC– bond of C2H2 molecules, and C–H···π interactions play an important role in the separation of C2H2/CO2 selective mixtures. In addition, owing to the pore size and electrostatic effect, FJU-129 selectively absorbs MB and excludes other cationic dyes and anionic dyes (MB, CV, RB, R6G, MO, and SD-III). [ABSTRACT FROM AUTHOR]

Rational design of high nuclear copper cluster‐based metal–organic frameworks has not been established yet. Herein, we report a novel MOF (FJU‐112) with the ten‐connected tetranuclear copper cluster [Cu4(PO3)2(μ2‐H2O)2(CO2)4] as the node which was capped by the deprotonated organic ligand of H4L (3,5‐Dicarboxyphenylphosphonic acid). With BPE (1,2‐Bis(4‐pyridyl)ethane) as the pore partitioner, the pore spaces in the structure of FJU‐112 were divided into several smaller cages and smaller windows for efficient gas adsorption and separation. FJU‐112 exhibits a high separation performance for the C2H2/CO2 separation, which were established by the temperature‐dependent sorption isotherms and further confirmed by the lab‐scale dynamic breakthrough experiments. The grand canonical Monte Carlo simulations (GCMC) studies show that its high C2H2/CO2 separation performance is contributed to the strong π‐complexation interactions between the C2H2 molecules and framework pore surfaces, leading to its more C2H2 uptakes over CO2 molecules. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Acetylene purification from methane is challenging in the field of porous organic polymers (POPs). Herein, we have provided one‐pot Ullmann coupling reaction to synthesize a series of POPs with rich N‐sites, named FJU‐POP‐n, wherein the low‐cost and non‐toxic Cu(acac)2 and environmental‐friendly glycerol are employed as catalyst and solvent, respectively. These POPs constructed by aromatic amine and haloarene monomers exhibit different steric configurations and pore sizes. Among these, FJU‐POP‐4 with abundant N‐functional sites and suitable pore size exhibits ultra‐high selective separation for C2H2/CH4 (307.1, 50 : 50) at ambient conditions, the highest among the reported MOFs and POPs with nitrogen‐sites as only functional species. Dynamic fixed bed breakthrough and regeneration experiments confirm structural stability and reproducibility, indicating their promising application in selective separation. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Acetylene purification from methane is challenging in the field of porous organic polymers (POPs). Herein, we have provided one‐pot Ullmann coupling reaction to synthesize a series of POPs with rich N‐sites, named FJU‐POP‐n, wherein the low‐cost and non‐toxic Cu(acac)2 and environmental‐friendly glycerol are employed as catalyst and solvent, respectively. These POPs constructed by aromatic amine and haloarene monomers exhibit different steric configurations and pore sizes. Among these, FJU‐POP‐4 with abundant N‐functional sites and suitable pore size exhibits ultra‐high selective separation for C2H2/CH4 (307.1, 50 : 50) at ambient conditions, the highest among the reported MOFs and POPs with nitrogen‐sites as only functional species. Dynamic fixed bed breakthrough and regeneration experiments confirm structural stability and reproducibility, indicating their promising application in selective separation. [ABSTRACT FROM AUTHOR]

The efficient separation of acetylene (C2H2) from carbon dioxide (CO2) and CnH4 (n = 1 and 2) to manufacture high purity C2H2 and recover other light hydrocarbons is technologically important, while posing significant challenges. Herein, we reported a new TiF62− anion (TIFSIX) pillared metal-organic framework (MOF) ZNU-5 (ZNU = Zhejiang Normal University) with ultramicropores for highly selective C2H2 capture with low adsorption heat through gate opening based molecular sieving effect. ZNU-5 takes up a large amount of C2H2 (128.6 cm3/g) at 1.0 bar and 298 K but excludes CO2, CH4, and C2H4. Such high capacity has never been realized in MOFs with molecular sieving. The breakthrough experiments further confirmed the highly selective C2H2 separation performance from multi-component gas mixtures. 3.3, 2.8, and 2.2 mmol/g of C2H2 is captured at ZNU-5 from equimolar C2H2/CO2, C2H2/CO2/CH4, and C2H2/CO2/CH4/C2H4 mixtures, respectively. Furthermore, 2.6, 2.0, and 1.5 mmol/g of > 98% purity C2H2 can be recycled from the desorption process. Combining high working capacity, low adsorption heat, as well as good recyclability, ZNU-5 is promising for C2H2 purification. [ABSTRACT FROM AUTHOR]

Two 2-fold interpenetrating MOFs (CTGU-39/40-a) with 1D/3D microporous pore systems were constructed to achieve efficient separation for C 2 H 2 /CO 2 mixture. Attributed to the confinement of C 2 H 2 through multiple C 2 H 2 -MOF interactions, CTGU-39-a combines ultra-high C 2 H 2 packing density, excellent C 2 H 2 /CO 2 selectivity and relatively low Q st of C 2 H 2. [Display omitted] • Two 2-fold interpenetrating MOFs (CTGU-39/40-a) with novel pore systems and diverse adsorption sites have been constructed. • CTGU-39/40-a can effectively separate C 2 H 2 /CO 2 mixture confirmed by both static adsorption and breakthrough experiments. • CTGU-39-a combines ultra-high C 2 H 2 packing density, excellent adsorption selectivity, and a relatively low C 2 H 2 Q st. Adsorptive separation of C 2 H 2 /CO 2 is industrially important and feasible but the design of highly efficient adsorbents remains very challenging owing to the almost identical physicochemical properties of the two gases. Herein, we constructed two new microporous metal–organic frameworks (MOFs), termed CTGU-39/40 (CTGU = China Three Gorges University), with 2-fold interpenetrating frameworks and unique pore geometry/chemistry for C 2 H 2 /CO 2 separation. Both the activated MOFs (CTGU-39/40-a) can preferentially adsorb C 2 H 2 over CO 2 with excellent selectivity of 8.4 and 3.3 at 298 K and 100 kPa, respectively, as verified by static adsorption measurements. More importantly, attributed to the suitable pore aperture size (∼5 Å) and abundant adsorption sites, CTGU-39-a combines exceptionally high packing density of C 2 H 2 (0.41 g mL−1) and moderate isosteric heat of adsorption (Q st) for C 2 H 2 (26.8 kJ mol−1), outperforming most previously reported adsorbents. Theoretical calculations reveal that the preferential adsorption of C 2 H 2 within two MOFs is driven by cooperative adsorption behavior through multiple H-bonding and Coulomb interactions. Experimental breakthrough results further confirmed their practical separation ability and recyclability toward an equimolar C 2 H 2 /CO 2 mixture at different feeding rates. This work may offer new insights into the design of advanced porous materials for C 2 H 2 purification and potentially other gas separations. [ABSTRACT FROM AUTHOR]

The separation of C2H2/CO2 is not only industrially important for acetylene purification but also great scientific challenge due to their very similar molecular size and physical properties. To address this difficulty, herein, we present an ultramicroporous hydrogen‐bonded organic framework (HOF‐FJU‐1) from tetracyano bicarbazole to separate C2H2 from CO2 by taking advantage of differences in their electrostatic potential distribution. This material possesses a suitable pore environment and electrostatic potential distribution fitting well to C2H2, thus showing extra strong affinity to C2H2 (46.73 kJ mol−1) and the highest IAST selectivity of 6675 for C2H2/CO2 separation among the adsorbents reported. The single crystal X‐ray diffraction reveals that the suitable pore environment in HOF‐FJU‐1 provides multiple C−H⋅⋅⋅π and hydrogen‐bonded interactions N⋅⋅⋅H−C with C2H2 molecules. Dynamic breakthrough experiments demonstrate its outstanding separation performance to C2H2/CO2 mixtures. [ABSTRACT FROM AUTHOR]

Selective-adsorption separation is an energy-efficient technology for the capture of acetylene (C2H2) from carbon dioxide (CO2) and ethylene (C2H4). However, it remains a critical challenge to effectively recognize C2H2 among CO2 and C2H4, owing to their analogous molecule sizes and physical properties. Herein, we report a new microporous metal–organic framework (NUM-14) possessing a carefully tailored pore system containing moderate pore size and nitro-functionalized channel surface for efficient separation of C2H2 from CO2 and C2H4. The activated NUM-14 (namely NUM-14a) exhibits sufficient pore space to acquire excellent C2H2 loading capacity (4.44 mmol g−1) under ambient conditions. In addition, it possesses dense nitro groups, acting as hydrogen bond acceptors, to selectively identify C2H2 molecules rather than CO2 and C2H4. The breakthrough experiments demonstrate the good actual separation ability of NUM-14a for C2H2/CO2 and C2H2/C2H4 mixtures. Furthermore, Grand Canonical Monte Carlo simulations indicate that the pore surface of the NUM-14a has a stronger affinity to preferentially bind C2H2 over CO2 and C2H4 via stronger C-H···O hydrogen bond interactions. This article provides some insights into customizing pore systems with desirable pore sizes and modifying groups in terms of MOF materials toward the capture of C2H2 from CO2 and C2H4 to promote the development of more MOF materials with excellent properties for gas adsorption and separation. [ABSTRACT FROM AUTHOR]

Emerging covalent organic frameworks (COFs) have received great attention for their unique features, but the limited building blocks restrict their structural diversity and performance exploration. Reticular chemistry provides guidance for the structural expansion and performance regulation of COFs. Herein, we constructed two novel two-dimensional (2D) COFs functionalized with cyclopentadienyl cobalt, denoted as UPC-COF-1 and UPC-COF-2, via [4+2] imine condensation with diamine building blocks of different length. Theoretical simulations combined with experimental results reveal that UPC-COF-1 with shorter building blocks, narrower pore sizes, and stronger host-guest interactions has better C2H2/CO2 separation performance. In addition, UPC-COF-1 can maintain separation stability in the presence of water vapor and methane impurities. This work provides a new evidence for the performance regulation of isoreticular COFs with modular and tunable building blocks., (© 2024 Wiley‐VCH GmbH.)

A novel potassium‐based metal organic framework (TCBPA‐K) was prepared by using a C3‐symmetric organic building block tris(4′‐carboxybiphenyl)amine (TCBPA). The compound has a rectangular like channel along the b axis and exhibits good selective adsorption performance. The single component gas adsorption isotherms indicated that the adsorption capacity of C2H2 is much higher than that of CO2 at 298 K and 1 bar. The isosteric adsorption enthalpies of TCBPA‐K for C2H2 and CO2 are 30.6 kJ/mol and 9.1 kJ/mol respectively. Ideal adsorbed solution theory calculation recorded the separation selectivity of C2H2/CO2 (50/50, v/v) as 3.5. [ABSTRACT FROM AUTHOR]

By employing the N-H···N hydrogen-bonding tetramers to connect the pyrazole monomers, we realize the reticular syntheses of three isostructural HOFs (HOF-FJU-45, HOF-FJU-46 and HOF-FJU-47) with tunable pore environments and enhanced C 2 H 2 /CO 2 separation performance. [Display omitted] • Confirmed that reticular chemistry can also be realized in HOFs by employing the N-H···N hydrogen-bonding tetramers to connect the pyrazole monomers. • The pore sizes and electrostatic potential can be regulated by the alteration of tetrahedral building block core. • The complementary electrostatic potential towards C 2 H 2 enable HOF-FJU-47a exhibits better C 2 H 2 /CO 2 separation performance compare to HOF-FJU-45a and HOF-FJU-46a. • Breakthrough experiments demonstrate that HOF-FJU-47a can efficiently separate C 2 H 2 /CO 2 mixtures. Reticular chemistry has been widely used to predict and design structures of MOFs and COFs, but it still limited in HOFs due to the flexible and fragile nature of hydrogen bonding. Herein, by employing the N-H···N hydrogen-bonding tetramers to connect the pyrazole monomers, we realize the reticular syntheses of three isostructural HOFs (HOF-FJU-45, HOF-FJU-46 and HOF-FJU-47) with tunable pore environments and explore their separation performance toward C 2 H 2 /CO 2 mixtures. Among these three HOFs, the electrostatic potential of pore surface in HOF-FJU-47a with tetraphenyladamantane core is complementary to C 2 H 2 , enabling it to perform better C 2 H 2 /CO 2 separation performance than HOF-FJU-45a with tetraphenylmethane core and HOF-FJU-46a with tetraphenylsilane core. Dynamic breakthrough experiments also confirm that HOF-FJU-47a can achieve superior C 2 H 2 /CO 2 separation performance with a balanced C 2 H 2 working capacity (1.98 mmol g−1) and separation factor (5.5) in HOFs materials. The multiple host–guest interactions between C 2 H 2 and the framework of HOF-FJU-47a are further revealed by theoretical calculations. [ABSTRACT FROM AUTHOR]

[Display omitted] • The insertion of pillar ligands of UPC-190 series MOFs can lead to changes in the interpenetrating structure. The degree of interpenetration can be managed by introducing different pillars. • Theoretical calculations demonstrate that the fluorine atom on pillar ligands is an effective interaction site for C 2 H 2 molecules. This means that fluorine atoms can act as active sites that interact with C 2 H 2 molecules, thereby influencing their adsorption behavior. • The formation of interpenetrating structures and the stepwise fluorination strategy gradually improve the IAST selectivity and C 2 H 2 uptake of the sample. This strategy proves guidance for designing MOFs for challenging gas separations. The efficient separation of C 2 H 2 /CO 2 possesses great commercial and research value and remains challenging due to their similar molecular sizes and physical properties. Functionalization is a powerful strategy for precisely regulating the pore environment of porous adsorbents, notably metal–organic frameworks (MOFs), for recognizing target molecules. Here, we construct three interpenetrated MOFs using a stepwise fluorinated pillar-ligand strategy. Interestingly, the degree of interpenetration can be managed by introducing different pillars. The unique interpenetrating structure cooperates with fluorine-rich pore environment significantly improves the C 2 H 2 uptake and the C 2 H 2 /CO 2 separation selectivity. The optimized difluorine-functionalized UPC-193 exhibits the highest C 2 H 2 adsorption capacity (80.45 cm3/g) and separation efficiency (C 2 H 2 /CO 2 uptake ratio of 1.9) among UPC-190 systems at ambient conditions. Ideal adsorbed solution theory (IAST) calculations, molecular modeling studies, and breakthrough experiments comprehensively demonstrate that UPC-193 is an effective MOF adsorbent for equimolar C 2 H 2 /CO 2 separation. The stepwise pillar-ligand fluorination strategy proves to be an effective approach to extend the functionality of MOFs for challenging gas separations. [ABSTRACT FROM AUTHOR]

Pillar-layered metal-organic frameworks (PLMOFs) are promising gas adsorbents due to their high designability. In this work, high CO 2 storage capacity as well as controllable C 2 H 2 /CO 2 separation ability are acquired by rationally manipulating the interlayer stacking in pillar-layered MOF materials. The rational construction of pillar-layered MOFs started from the 2D Ni-BTC-pyridine layer, an isomorphic structure of pioneering MOF-1 reported in 1995. The replacement of terminal pyridine groups by bridging pyrazine linkers under optimized solvothermal conditions led to three 3D PLMOFs with different stacking types between adjacent Ni-BTC layers, named PLMOF 1 (ABAB stacking), PLMOF 2 (AABB stacking), and PLMOF 3 (AAAA stacking). Regulated by the layer arrangements, CO 2 and C 2 H 2 adsorption capacities (273 K and 1 bar) of PLMOFs 1-3 vary from 173.0/153.3, 185.0/162.4, to 203.5/159.5 cm 3 g -1 , respectively, which surpass the values of most MOF adsorbents. Dynamic breakthrough experiments further indicate that PLMOFs 1-3 have controllable C 2 H 2 /CO 2 separation performance, which can successfully overcome the C 2 H 2 /CO 2 separation challenge. Specially, PLMOFs 1-3 can remove trace CO 2 (3%) from the C 2 H 2 /CO 2 mixture and produce high-purity ethylene (99.9%) in one step with the C 2 H 2 productivities of 1.68, 2.45, and 3.30 mmol g -1 , respectively. GCMC simulations indicate that the superior CO 2 adsorption and unique C 2 H 2 /CO 2 separation performance are mainly ascribed to different degrees of CO 2 agglomeration in the ultramicropores of these PLMOFs.

The separation of C2H2/CO2 is an important process in industry but challenged by the trade‐off of capacity and selectivity owning to their similar physical properties and identical kinetic molecular size. We report the first example of symmetrically interpenetrated dodecaborate pillared MOF, ZNU‐1, for benchmark selective separation of C2H2 from CO2 with a high C2H2 capacity of 76.3 cm3 g−1 and record C2H2/CO2 selectivity of 56.6 (298 K, 1 bar) among all the robust porous materials without open metal sites. Single crystal structure analysis and modeling indicated that the interpenetration shifting from asymmetric to symmetric mode provided optimal pore chemistry with ideal synergistic "2+2" dihydrogen bonding sites for tight C2H2 trapping. The exceptional separation performance was further evidenced by simulated and experimental breakthroughs with excellent recyclability and high productivity (2.4 mol kg−1) of 99.5 % purity C2H2 during stepped desorption process. [ABSTRACT FROM AUTHOR]

Selective-adsorption separation is an energy-efficient technology for the capture of acetylene (C2H2) from carbon dioxide (CO2) and ethylene (C2H4). However, it remains a critical challenge to effectively recognize C2H2 among CO2 and C2H4, owing to their analogous molecule sizes and physical properties. Herein, we report a new microporous metal–organic framework (NUM-14) possessing a carefully tailored pore system containing moderate pore size and nitro-functionalized channel surface for efficient separation of C2H2 from CO2 and C2H4. The activated NUM-14 (namely NUM-14a) exhibits sufficient pore space to acquire excellent C2H2 loading capacity (4.44 mmol g−1) under ambient conditions. In addition, it possesses dense nitro groups, acting as hydrogen bond acceptors, to selectively identify C2H2 molecules rather than CO2 and C2H4. The breakthrough experiments demonstrate the good actual separation ability of NUM-14a for C2H2/CO2 and C2H2/C2H4 mixtures. Furthermore, Grand Canonical Monte Carlo simulations indicate that the pore surface of the NUM-14a has a stronger affinity to preferentially bind C2H2 over CO2 and C2H4 via stronger C-H···O hydrogen bond interactions. This article provides some insights into customizing pore systems with desirable pore sizes and modifying groups in terms of MOF materials toward the capture of C2H2 from CO2 and C2H4 to promote the development of more MOF materials with excellent properties for gas adsorption and separation.

[Display omitted] • A novel [NbOF 5 ]2- pillared MOF is prepared with abundant electronegative sites. • Cooperative Nb-F···HC≡CH···F-Nb hydrogen bonding for strong C 2 H 2 capture. • Good C 2 H 2 capacity and high selectivity over CO 2 and C 2 H 4. • Excellent practical C 2 H 2 /CO 2 and C 2 H 2 /C 2 H 4 separation performance. Separating acetylene (C 2 H 2) from carbon dioxide (CO 2) and ethylene (C 2 H 4) presents a significant challenge in the industry due to their closely similar physical properties. Herein, we synthesized a novel [NbOF 5 ]2- pillared microporous metal–organic framework ZNU-11 with abundant electronegative sites for efficient C 2 H 2 /CO 2 and C 2 H 2 /C 2 H 4 adsorption separation. The uncoordinating fluorine atoms in the confined pores selectively capture C 2 H 2 from CO 2 and C 2 H 4 by hydrogen bonding interactions. The C 2 H 2 capacity of ZNU-11 is 45.5 cm3/g at 298 K and 100 kPa, over three folds of the C 2 H 4 uptake and two folds of the CO 2 uptake. The relatively modest C 2 H 2 adsorption heat of 36.1 kJ/mol facilitates the straightforward desorption and regeneration of ZNU-11. Furthermore, density functional theory (DFT) calculations confirmed the stronger binding of C 2 H 2 compared to CO 2 and C 2 H 4. Experimental breakthroughs with C 2 H 2 /CO 2 and C 2 H 2 /C 2 H 4 gas mixtures, coupled with excellent recyclability, validated the practical separation performance of ZNU-11. Notably, the dynamic separation factor of 4.2 for equimolar C 2 H 2 /CO 2 mixture rivals those of many benchmark materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two MOFs have been successfully synthesized using Pillar-Layer Strategy. • Two MOFs demonstrate exceptional stability and cost-effectiveness. • JLU-MOF103 exhibits high C 2 H 2 uptake and significant C 2 H 2 /CO 2 selectivity. • Theoretical calculations explain adsorption mechanism at a molecular-level. Acetylene and carbon dioxide share similar physical properties, which poses a significant challenge for their industrial separation. Therefore, it is crucial to design and synthesize specific physical adsorbents for this purpose. In this study, two pcu topological MOFs materials named JLU-MOF102 {[Ni(HPyC) 2 (BPY)] (DMF) 2 (H 2 O) 2 } and JLU-MOF103 {[Ni(HPyC) 2 (PYZ)] (H 2 O) 2 } (4-pyrazolecarboxylic acid = H 2 PyC, 4,4′-bipyridine = BPY, pyrazine = PYZ, DMF = N, N- dimethylformamide), were successfully synthesized to facilitate the separation of C 2 H 2 and CO 2. These MOFs were synthesized by using the pillar-layered strategy, both having the same sql layer (combined Ni2+ and HPYC) but different pillar ligands (BPY for JLU-MOF102 and PYZ for JLU-MOF103 , respectively). The pore size of JLU-MOF103 is smaller than that of JLU-MOF102 and the interaction between JLU-MOF103 and C 2 H 2 molecules is stronger. JLU-MOF102 and JLU-MOF103 exhibit significant ability to capture C 2 H 2 (125.8 and 96.7 cm3/g, respectively) and the selectivity for C 2 H 2 /CO 2 (v/v = 50/50) mixture is 4.5 and 14.0 calculated by IAST, respectively, at 298 K and 1 bar. First-principles-based calculations reveal subtle differences in host–guest interactions between JLU-MOF102 and JLU-MOF103 originated from the porous structures, which account for their distinct separation selectivity. The dynamic column breakthrough experiments demonstrated that JLU-MOF103 had a higher C 2 H 2 adsorption capacity of 2.01 mmol/g compared to JLU-MOF102 (1.16 mmol/g). The low cost, excellent stability and good recycling ability suggest the potential of JLU-MOF103 for industrial applications. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) have emerged as a multi-functional platform for selective gas capture and luminescent detection of harmful pollutants, in which their pore functionality and structural stability are two key factors to be considered for the targeted applications. In this contribution, we present the synthesis and structural evaluation of a new channel-type MOF formulated as {[In 3 (OH) 3 (TATAB) 2 ](DMA) 8 (CH 3 CN) 6 (H 2 O) 2 } n (1 , DMA is short for N,N-dimethylacetamide and TATAB is the abbreviation of 4,4′,4″-s-triazine-1,3,5-triyl-p-aminobenzoate) constructed from rod-like [In-(OH)-(COO) 2 ] n chains and the N-rich fluorescent triazine ligand H 3 TATAB. The noninterpenetrated framework of 1 features 1D rhombic channels (13.1 × 14.2 Å2) along the c axis with abundant of free N sites on the pore walls. The solvent-removal framework of 1 (1a) could adsorb large amount of C 2 H 2 (154 cm3/g) at 298 K and 1 bar with a moderate C 2 H 2 /CO 2 selectivity (3.7), and its separation performance has been further validated via the break-through experiments. Aqueous-phase sensing experiments demonstrate this MOF exhibits excellent performance of fluorescent detection of 2,4,6-trinitrophenol (TNP) via remarkable fluorescence quenching and obvious blue-shift of maximum emission. In connection to the sensing experiments, we used DFT calculations to reveal the underlying mechanism of such sensing performances via analyzing the energy lever together with electron transfer route. A new channel-type MOF with 1D rhombic channels and abundant of free N sites on the pore walls was synthesized. The solvent-removal framework could adsorb large amount of C 2 H 2 (154 cm3/g) at 298 K and 1 bar with a moderate C 2 H 2 /CO 2 selectivity (3.7), and its separation performance has been further validated via the break-through experiments. Aqueous-phase sensing experiments demonstrate this MOF exhibits excellent performance of fluorescent detection of 2,4,6-trinitrophenol via remarkable fluorescence quenching and obvious blue-shift of maximum emission. The sensing mechanism has also been studied both experimentally and computationally. [Display omitted] • An In(III)-organic framework with microporosity and a high BET surface area was achieved. • It shows a high C 2 H 2 uptake capacity at 298 K with a moderate C 2 H 2 /CO 2 selectivity. • It could detect 2,4,6-trinitrophenol via remarkable fluorescence quenching and obvious blue-shift of maximum emission. • The detailed sensing mechanism was studied via DFT calculations. [ABSTRACT FROM AUTHOR]

Adsorption‐based separation is an important technology for C2H2 purification due to the environmentally friendly and energy‐efficient advantage. In addition to the high selectivity of C2H2/CO2, the high uptake of C2H2 also plays an important role in the separation progress. However, the trade‐off between adsorption capacity and separation performance is still in a dilemma. Herein, we report a series of cage‐like porous materials named FJI‐H8‐R (R=Me, Et, nPr and iPr) which all have high C2H2 uptakes at 1 bar and 298 K. Dynamic breakthrough studies show that they all exhibit excellent C2H2/CO2 separation performance. Particularly, FJI‐H8‐Me possesses a long breakthrough time up to 90 min g−1. Additionally, Grand Canonical Monte Carlo (GCMC) simulation reveals that the suitable pore space and geometry contribute much to the excellent separation performance. [ABSTRACT FROM AUTHOR]

Despite much intense investigation on the C2H2/CO2 separation, the trade‐off between the adsorption capacity and separation selectivity is still tricky. To overcome the dilemma, we have rationally synthesized an ultra‐stable fluorinated hybrid porous material SIFSIX‐Cu‐TPA with the ith‐d topology. Completely differing from the famous pillar‐layer fluorinated materials, SIFSIX‐Cu‐TPA possesses a unique pillar‐cage structure, in which the SiF62− anions cross‐link two adjacent metal nodes as pillars to stabilize the three‐dimensional framework constructed by icosahedral and tetrahedral cages. As anticipated, SIFSIX‐Cu‐TPA has high BET surface area (1330 m2 g−1) as well as high C2H2 uptake (185 cm3 g−1 at 298 K and 1 bar). At the same time, due to the obvious difference in the adsorption performance of CO2 and C2H2 especially in the low pressure area, SIFSIX‐Cu‐TPA also exhibits an excellent C2H2/CO2 separation performance (breakthrough time up to 68 min g−1 at 298 K and 1 bar). [ABSTRACT FROM AUTHOR]

Porous materials with open metal sites have been investigated to separate various gas mixtures. However, open metal sites show the limitation in the separation of some challenging gas mixtures, such as C2H2/CO2. Herein, we propose a new type of ultra‐strong C2H2 nano‐trap based on multiple binding interactions to efficiently capture C2H2 molecules and separate C2H2/CO2 mixture. The ultra‐strong acetylene nano‐trap shows a benchmark Qst of 79.1 kJ mol−1 for C2H2, a record high pure C2H2 uptake of 2.54 mmol g−1 at 1×10−2 bar, and the highest C2H2/CO2 selectivity (53.6), making it as a new benchmark material for the capture of C2H2 and the separation of C2H2/CO2. The locations of C2H2 molecules within the MOF‐based nanotrap have been visualized by the in situ single‐crystal X‐ray diffraction studies, which also identify the multiple binding sites accountable for the strong interactions with C2H2. [ABSTRACT FROM AUTHOR]

Safely and highly selective acetylene (C2H2) capture is a great challenge, because of its highly explosive nature, as well as its nearly similar molecule size and boiling point toward the main impurity of carbon dioxide (CO2). Adsorption separation has shown a promising future. Herein, a new nanoporous coordination polymer (PCP) adsorbent with fixed and free Cu ions (termed NTU-66-Cu) was prepared through post-synthetic approach via cation exchanging from the pristine NTU-66, an anionic framework with new 3, 4, 6-c topology and two kinds of cages. The NTU-66-Cu shows significantly improved C2H2/CO2 selectivity from 6 to 32 (v/v: 1/1) or 4 to 42 (v/v: 1/4) at low pressure under 298 K, along with enhanced C2H2 capacity (from 89.22 to 111.53 cm3·g−1). More importantly, this observation was further validated by density functional theory (DFT) calculations and breakthrough experiments under continuous and dynamic conditions. Further, the excellent chemical stability enables this adsorbent to achieve recycle C2H2/CO2 separation without loss of C2H2 capacity. [ABSTRACT FROM AUTHOR]

A novel Co(II)-containing metal–organic framework [Co3(OH)2(H2TCPP)2](DMF)3 (1) based on a linear trinuclear Co(II) cluster-based unit has been successfully prepared by using a nanosized tetracarboxylate ligand 2,3,5,6-tetrakis(4-carboxyphenyl)pyrazine (H4TCPP) as the organic building block under the solvothermal reaction. Gas adsorption studies reveal that the mixtures of C2H2/CH4 and C2H2/CO2 could be selectively separated by the obtained resulting solvent free 1 (denoted as 1a hereafter). To deep evaluate the protective function of complex for acute glomerulonephritis (AGN) disease in vitro, the following experiments were conducted. (a) Real time Reverse transcription-Polymerase Chain Reaction (RT-PCR) was carried out to determine the relative expression of Nuclear factor kappa beta (nf-κb) and Tumor Necrosis Factor-α (tnf-α) in the glomerulus cells after bacterial infection along with complex 1 treatment. (b) The enzyme linked immunosorbent assay (ELISA) was conducted to determine the IL-1β and IL-6 released by glomerular cells after complex 1 treatment. (c) The results obtained through molecular docking exhibited possible regulation mechanism on the binding affinity between compound 1 and target protein. [ABSTRACT FROM AUTHOR]

The development of porous metal–organic framework (MOF) solids displaying efficient separation and purification of acetylene is of cardinal significance but challenging in the chemical industry. Among the reported MOFs for such a purpose, there usually exists an issue associated with trade-off between the uptake capacity and adsorption selectivity. In this work, we employed an N-oxide-functionalized dicarboxylate ligand to successfully construct under suitable solvothermal conditions a dicopper paddlewheel-based MOF featuring two different types of nanocages and rich open oxygen atoms on the channel surface. These structural features endow the material with the promising potential for C2H2 recovery from CO2 and CH4 at ambient conditions with impressive adsorption selectivity of C2H2 over CO2 and CH4 as well as considerable C2H2 capture capacity, which have been validated by isotherm measurements, ideal adsorbed solution theory calculations, and breakthrough experiments. Furthermore, molecular modeling studies revealed the vital role that the oxygen atoms coming from both N-oxide moieties and carboxylate groups play in selectively recognizing C2H2 over CO2 and CH4. [ABSTRACT FROM AUTHOR]

• A new metal-organic framework was prepared. • It showed discriminating sorption performance toward C 2 H 2 over CO 2. • The sorption mechanism was studied via GCMC simulations. Acetylene is an important industrial material for the production of acetaldehyde, acetic acid, benzene, synthetic rubber, synthetic fiber, etc., and its separation from the gas mixtures of C 2 H 2 /CO 2 is of great importance but a challenging task due to their similar physical properties and molecular sizes. In this study, taking the advantage of open-donor sites on the pore surface as the nano-traps for C 2 H 2 molecules, a new microporous metal-organic framework (MOF) formulated as {[C o 3 (OH) 2 (HCOO) 2 (CPT) 2 ](NMF) 2 (MeOH) 3 (H 2 O)} n (1 , NMF = N - methylformamide) has been prepared by virtue of a bifunctional organic ligand 4-(4H-1,2,4-triazol-4-yl)benzoic acid (HCPT), which showed discriminating sorption performance toward C 2 H 2 (113 cm3/g at 298 K and 1 bar) over CO 2 (33 cm3/g) under the same conditions. The different sorption behavior of {[C o 3 (OH) 2 (HCOO) 2 (CPT) 2 ]} n between C 2 H 2 and CO 2 results in a high uptake ration (3.4:1) and IAST selectivity (13) at 298 K and 1 bar. Furthermore, the force-field based grand canonical Monte Carlo (GCMC) simulation results demonstrate that the large electronegativity and polarizability of open O donor sites on the pore surface contribute to its high C 2 H 2 /CO 2 separation performance, leading to its more favorable C 2 H 2 uptakes than CO 2. A new microporous metal-organic framework has been prepared by virtue of a bifunctional organic ligand 4-(4H-1,2,4-triazol-4-yl)benzoic acid, which showed discriminating sorption performance toward C 2 H 2 over CO 2 under the same conditions. The different sorption behavior of {[C o 3 (OH) 2 (HCOO) 2 (CPT) 2 ]} n between C 2 H 2 and CO 2 results in a high uptake ration (3.4:1) and IAST selectivity (13) at 298 K and 1 bar. Furthermore, the force-field based grand canonical Monte Carlo (GCMC) simulation results demonstrate that the large electronegativity and polarizability of open O donor sites on the pore surface contribute to its high C 2 H 2 /CO 2 separation performance. [Display omitted] [ABSTRACT FROM AUTHOR]

A highly water and thermally stable metal-organic framework (MOF) Zn2(Pydc)(Ata)2 (1, H2Pydc = 3,5-pyridinedicarboxylic acid; HAta = 3-amino-1,2,4-triazole) was synthesized on a large scale using inexpensive commercially available ligands for efficient separation of C2H2 from CH4 and CO2. Compound 1 could take up 47.2 mL/g of C2H2 under ambient conditions but only 33.0 mL/g of CO2 and 19.1 mL/g of CH4. The calculated ideal absorbed solution theory (IAST) selectivities for equimolar C2H2/CO2 and C2H2/CH4 were 5.1 and 21.5, respectively, comparable to those many popular MOFs. The Qst values for C2H2, CO2, and CH4 at a near-zero loading in 1 were 43.1, 32.1, and 22.5 kJ mol−1, respectively. The practical separation performance for C2H2/CO2 mixtures was further confirmed by column breakthrough experiments.

Adsorptive separation technology provides an effective approach for separating gases with similar physicochemical properties, such as the purification of acetylene (C 2 H 2 ) from carbon dioxide (CO 2 ). The high designability and tunability of metal-organic framework (MOF) adsorbents make them ideal design platforms for this challenging separation. Herein, we employ an isoreticular functionalization strategy to fine-tune the pore environment of Zr- and Th-based UiO-66 by the immobilization of the benzothiadiazole group via bottom-up synthesis. The functionalized UPC-120 exhibits an enhanced C 2 H 2 /CO 2 separation performance, which is confirmed by adsorption isotherms, dynamic breakthrough curves, and theoretical simulations. The synergy of ligand functionalization and metal ion fine-tuning guided by isoreticular chemistry provides a new perspective for the design and development of adsorbents for challenging gas separation processes.

Acetylene (C 2 H 2 ) is widely used as a raw material for producing various downstream commodities in the petrochemical and electronic industry. Therefore, the acquisition of high-purity C 2 H 2 from a C 2 H 2 /CO 2 mixture produced by partial methane combustion or thermal hydrocarbon cracking is of great significance yet highly challenging due to their similar physical and chemical properties. Herein, we report an anionic metal-organic framework (MOF) named LIFM-210, which has Li + cations in the pores and shows a higher adsorption affinity for C 2 H 2 than CO 2 . LIFM-210 is constructed by a unique tetranuclear Ni(II) cluster acting as a 10-connected node and an organic ligand acting as a 5-connected node. Single-component adsorption and transient breakthrough experiments demonstrate the good C 2 H 2 selective separation performance of LIFM-210. Theoretical calculations revealed that Li + ions strongly prefer C 2 H 2 to CO 2 and are primary adsorption sites, playing vital roles in the selective separation of C 2 H 2 /CO 2 .

Safely and highly selective acetylene (C2H2) capture is a great challenge, because of its highly explosive nature, as well as its nearly similar molecule size and boiling point toward the main impurity of carbon dioxide (CO2). Adsorption separation has shown a promising future. Herein, a new nanoporous coordination polymer (PCP) adsorbent with fixed and free Cu ions (termed NTU-66-Cu) was prepared through post-synthetic approach via cation exchanging from the pristine NTU-66, an anionic framework with new 3, 4, 6-c topology and two kinds of cages. The NTU-66-Cu shows significantly improved C2H2/CO2 selectivity from 6 to 32 (v/v: 1/1) or 4 to 42 (v/v: 1/4) at low pressure under 298 K, along with enhanced C2H2 capacity (from 89.22 to 111.53 cm3·g−1). More importantly, this observation was further validated by density functional theory (DFT) calculations and breakthrough experiments under continuous and dynamic conditions. Further, the excellent chemical stability enables this adsorbent to achieve recycle C2H2/CO2 separation without loss of C2H2 capacity. [ABSTRACT FROM AUTHOR]

A strategy called ultramicroporous building unit (UBU) is introduced. It allows the creation of hierarchical bi‐porous features that work in tandem to enhance gas uptake capacity and separation. Smaller pores from UBUs promote selectivity, while larger inter‐UBU packing pores increase uptake capacity. The effectiveness of this UBU strategy is shown with a cobalt MOF (denoted SNNU‐45) in which octahedral cages with 4.5 Å pore size serve as UBUs. The C2H2 uptake capacity at 1 atm reaches 193.0 cm3 g−1 (8.6 mmol g−1) at 273 K and 134.0 cm3 g−1 (6.0 mmol g−1) at 298 K. Such high uptake capacity is accompanied by a high C2H2/CO2 selectivity of up to 8.5 at 298 K. Dynamic breakthrough studies at room temperature and 1 atm show a C2H2/CO2 breakthrough time up to 79 min g−1, among top‐performing MOFs. Grand canonical Monte Carlo simulations agree that ultrahigh C2H2/CO2 selectivity is mainly from UBU ultramicropores, while packing pores promote C2H2 uptake capacity. [ABSTRACT FROM AUTHOR]

By virtue of a 4-connected rectangular-planar organic ligand 3,3′,5,5′-azobenzenetetracar-boxylate (ABTC4−), a new porous metal-organic framework (MOF) with the chemical formula of {[Zn 2 (ABTC)(H 2 O) 2 ](DMA) 3 (H 2 O) 3 } n (1) has been prepared. This MOF is constructed from the {Zn 2 (CO 2) 4 } cluster-based unit and shows two types of cages (octahedral and cuboctahedral cages) in the framework. Due to its cage-type network, open Zn2+ functional sites along with the azo groups functionalized pores, the resulting activated 1a displays high C 2 H 2 storage capacity of C 2 H 2 (179 cm3/g) at 298 K and 1 bar as well as a moderate high separation selectivity for equimolar C 2 H 2 /CO 2 at 298 K. In addition, the molecular simulations were further performed to understand the different gas sorption performances. A new porous metal-organic framework has been successfully obtained by using a 4-connected rectangular-planar organic ligand 3,3′,5,5′-azobenzenetetracar-boxylate. Due to this cage-type network, open Zn2+ functional sites as well as azo groups functionalized pores, the resulting activated 1a displays high C 2 H 2 storage capacity of C 2 H 2 (179 cm3/g) at 298 K and 1 bar as well as a moderate high separation selectivity for equimolar C 2 H 2 /CO 2 at 298 K. In addition, the molecular simulations were further performed to understand the gas –framework interactions. Unlabelled Image • A new polyhedron-based metal−organic framework has been synthesized. • It comprises of octahedral and cuboctahedral cages and exhibits two types of channels along the a, b and c axis. • The solvent-free sample shows high C 2 H 2 adsorption capacities and a moderate high C 2 H 2 /CO 2 selectivity around room temperature. [ABSTRACT FROM AUTHOR]

• Efficient separation of acetylene/carbon dioxide mixture by T-shaped adsorption sites. • FJU-83 showed extremely high stability up to 470 °C and can retain intact in aqueous solutions with the pH value ranging from 1 to 12 without phase change. • The guest of acetylene was determined using single-crystal X-ray technology revealing that C 2 H 2 molecules are found to preferentially bind the organic moieties by C-H∙∙∙π and π∙∙∙π multiple intermolecular interactions in a T-type aromatic space. It is challenging to achieve high-purity acetylene (C 2 H 2) from the methylene (CH 4) and carbon dioxide (CO 2), due to their similar molecular structure and physical properties. Adsorption utilized porous materials, such as metal–organic frameworks (MOFs), has been considered as cost- and energy-efficient technology to separate acetylene mixtures. Herein, we reported a highly stable MOF, [Zn 6 L 4 (Me 2 NH 2 +) 4 ‧3H 2 O] (named FJU-83), featuring T-shaped functional capture sites explored for acetylene capture and separation. In addition, FJU-83a exhibits not only a high C 2 H 2 uptake capacity of 122.9 cm3/g at 273 K, 1 bar, but also good C 2 H 2 /CH 4 and C 2 H 2 /CO 2 selectivity of 24 and 2.9 under moderate temperature and 1 bar, respectively. The high separation efficiency of the C 2 H 2 /CH 4 and C 2 H 2 /CO 2 are validated by dynamic fixed bed breakthrough experiments. The single crystal X-ray diffraction studies and Hirshfeld surface analysis revealed that T-type aromatic sites of FJU-83a can separate C 2 H 2 from CH 4 and CO 2 through multiple C-H∙∙∙π and π∙∙∙π interactions. [ABSTRACT FROM AUTHOR]

• The C 2 H 2 molecules are adsorbed in the pore channel of PCN-200 in a commensurate manner. • Dynamic separation of C 2 H 2 /CO 2 is achieved. • The C 2 H 2 molecule is strongly oriented to the two uncoordinated oxygen atoms on the pore surface with a side-on style. Separating acetylene and carbon dioxide is a significant challenge due to their similar physicochemical properties. Herein, we reported an ultramicroporous metal–organic framework, PCN-200, which possesses narrow zig-zag one-dimensional channels with a size of about 4.5 Å. The pore surface of PCN-200 features numerous uncoordinated oxygen polar sites that are symmetrically distributed, facilitating the strong and commensurate binding of acetylene molecules (57.0 kJ mol−1). At 298 K and 1 bar, PCN-200 demonstrates a high selectivity (6.4) towards acetylene over carbon dioxide, and this separation performance is validated through dynamic breakthrough experiments. Simulation studies were conducted to gain insight into the adsorption mechanism for acetylene and carbon dioxide molecules in PCN-200. [ABSTRACT FROM AUTHOR]

• Zn 4 O(NTB) 2 MOF with 3D channels and rich oxygen sites for C 2 H 2 -selective adsorption. • Realized high C 2 H 2 uptake and excellent C 2 H 2 /CO 2 and C 2 H 2 /CH 4 selectivity. • Simulation elucidates oxygen sites responsible for binding C 2 H 2 molecules. • Zn 4 O(NTB) 2 exhibits good separation performance and outstanding cycling stability. Highly selective separation of acetylene from various other gases (e.g., carbon dioxide and methane) is of great importance in the petrochemical industry but remains a challenge due to their similar sizes and physical properties. Herein, we reported a microporous metal − organic framework Zn 4 O(NTB) 2 (H 3 NTB = 4,4′,4″-nitrilotribenzoicacid acid), features oxygen binding sites explored for C 2 H 2 capture and separation. A high C 2 H 2 uptake of 2.62 mmol g−1 combined with excellent selectivity of C 2 H 2 /CO 2 (4.8) and C 2 H 2 /CH 4 (21.6) under ambient conditions (i.e., 50:50 mixture at 298 K and 1 bar) was realized. Moreover, the grand canonical Monte Carlo (GCMC) simulations and first-principles density functional theory (DFT) calculations have identified that the high C 2 H 2 capture and selectivity ascribe to oxygen sites on the pores (C–H...O interaction). Dynamic breakthrough experiments comprehensively demonstrate that Zn 4 O(NTB) 2 is a promising adsorbent for practical C 2 H 2 /CO 2 and C 2 H 2 /CH 4 separation. [ABSTRACT FROM AUTHOR]

[Display omitted] • For the first time, specific binding sites for C 2 H 2 are constructed utilizing the MOFs interpenetration nets. • The synergy of hydrogen bond anchoring and strong Tb···C C electrostatic interaction enhances the C 2 H 2 capture. • High C 2 H 2 capacity and excellent selectivity over CO 2 and C 2 H 4. • Detailed theoretical calculations explore the mechanism of host–guest combination. Efficient separation of C 2 H 2 /CO 2 and C 2 H 2 /C 2 H 4 is necessary and challenging for industrial processes. The traditional method of pore sieving has great limitations for separating gases with similar characteristics. Herein, we report a new case (UPC-80) with the help of C 2 H 2 anchoring traps constructed by 4-fold interpenetration nets for gas separation. The single-component adsorption isotherms indicate that UPC-80 adsorbs more C 2 H 2 than C 2 H 4 and CO 2 , resulting in high adsorption selectivities of 6.34 and 4.78 for C 2 H 2 /CO 2 and C 2 H 2 /C 2 H 4 at 298 K, respectively. Laboratory-scale fixed-bed breakthrough experiments verify the efficient separation ability of UPC-80 toward the C 2 H 2 /CO 2 and C 2 H 2 /C 2 H 4 gas mixtures, remaining separation stability with negligible capacity loss. Theoretical simulations confirm that the good separation performance can be attributed to the anchoring of C 2 H 2 by two Tb 2 (COO) 6 clusters in adjacent interpenetration nets, as well as the strong electrostatic interaction. UPC-80 makes the first exploration to obtain specific C 2 H 2 binding sites by interpenetrated networks, becoming an excellent candidate as porous adsorbent for separating C 2 H 2 /CO 2 and C 2 H 2 /C 2 H 4. [ABSTRACT FROM AUTHOR]

• Ni-Pz optimized from 20 Hoffman-type MOFs for benchmark C 2 H 2 /CO 2 separation. • Balance of high C 2 H 2 capacity, high C 2 H 2 /CO 2 selectivity and chemical stability. • Mechanism study by GCMC simulation and DFT calculation. • Excellent breakthrough recyclability and ultrahigh productivity. The separation of C 2 H 2 from CO 2 is an important process for industrial achievement of gaseous precursor C 2 H 2 , which is yet challenged by the well-known trade-off between capacity and selectivity derived from their close physical properties (such as the nearly identical kinetic molecular sizes). Herein, we experimentally screen a series of Hoffman-type metal organic frameworks (MOFs) and regulate the pore size and functionality by introducing different metal cation and organic linkers. We find that among the obtained MOFs, a Ni2+ based MOF (termed as Ni-Pz) shows the best performance of efficient C 2 H 2 separation from CO 2 , featuring both high capacity (106 cm3/g) and selectivity (10.8). Moreover, to the best of our knowledge, Ni-Pz has never been explored in C 2 H 2 related separation before and is the only MOF that balances the adsorption capacity (>100 cm3/g), selectivity (>10), adsorption heat (<45 kJ/mol) and stability (>400 °C; pH = 1–12). Grand Canonical Monte Carlo (GCMC) simulations reproduce the experimental results and reveal several typical binding configurations of C 2 H 2 /CO 2 in Ni-Pz. Density functional theory calculations corroborate that the binding configurations from GCMC are very stable and that C 2 H 2 has stronger binding affinity inside the cavity of Ni-Pz than CO 2. Practical separation performance is further demonstrated by dynamic breakthrough experiments with good recyclability. Overall, our findings highlight that the Ni-Pz MOF screened from various Hoffman-type MOFs is an excellent candidate for industrial application. [ABSTRACT FROM AUTHOR]

Rational design of high nuclear copper cluster-based metal-organic frameworks has not been established yet. Herein, we report a novel MOF (FJU-112) with the ten-connected tetranuclear copper cluster [Cu 4 (PO 3 ) 2 (μ 2 -H 2 O) 2 (CO 2 ) 4 ] as the node which was capped by the deprotonated organic ligand of H 4 L (3,5-Dicarboxyphenylphosphonic acid). With BPE (1,2-Bis(4-pyridyl)ethane) as the pore partitioner, the pore spaces in the structure of FJU-112 were divided into several smaller cages and smaller windows for efficient gas adsorption and separation. FJU-112 exhibits a high separation performance for the C 2 H 2 /CO 2 separation, which were established by the temperature-dependent sorption isotherms and further confirmed by the lab-scale dynamic breakthrough experiments. The grand canonical Monte Carlo simulations (GCMC) studies show that its high C 2 H 2 /CO 2 separation performance is contributed to the strong π-complexation interactions between the C 2 H 2 molecules and framework pore surfaces, leading to its more C 2 H 2 uptakes over CO 2 molecules., (© 2023 Wiley-VCH GmbH.)

[Display omitted] • A novel TIFSIX pillared MOF is prepared with unprecedented zsd topology. • Cooperative Ti-F···HC≡CH···N(DIB) hydrogen bonding for strong C 2 H 2 capture. • High C 2 H 2 capacity and high selectivity over CO 2 , C 2 H 4 , and CH 4. • Excellent practical C 2 H 2 separation performance from quaternary mixtures. The separation of acetylene (C 2 H 2) from carbon dioxide (CO 2) and other C 1 -C 2 light hydrocarbons is important to produce C 2 H 2 in high purity as well as recover other gases. However, it is challenged by the trade-off between the adsorption capacity and selectivity due to the similar physical properties. In this work, we reported a new TiF 6 2− anion (TIFSIX) pillared porous metal organic framework ZNU-4 (ZNU = Zhejiang Normal University) with unprecedented zsd topology for selective C 2 H 2 capture. The utilization of 1,4-di(1H-imidazol-1-yl)benzene (DIB) as the organic linker in ZNU-4 generates a highly twisted framework, resulting in a distinctive topological net with unique narrow 1D channels suitable for C 2 H 2 trap. ZNU-4 features robust-flexible isotherms for C 2 H 2 adsorption and the capacity under 1 bar and 298 K is as high as 85 cm3/g, 1.9, 2.1 and 7.1 folds of CO 2 , C 2 H 4 and CH 4 uptake. The IAST selectivity of C 2 H 2 over CO 2 , C 2 H 4 , CH 4 is 9, 12, and 300, respectively, higher than those of most popular porous materials. Modelling study indicated that C 2 H 2 is trapped by cooperative Ti-F···HC≡CH···N(DIB) hydrogen bonding along with other weak Van der Waals interactions. Such cooperative bonding interactions have never been disclosed in other fluorinated anions pillared MOFs due to the absence of second binding site from organic linkers. The breakthrough experiments further confirmed the highly selective C 2 H 2 separation performance from binary C 2 H 2 /CO 2 mixtures, ternary C 2 H 2 /CO 2 /CH 4 mixtures and quaternary C 2 H 2 /CO 2 /CH 4 /C 2 H 4 mixtures. The separation factor of ZNU-4 for equimolar C 2 H 2 /CO 2 mixture is 5.4, superior to those of many other benchmark materials. [ABSTRACT FROM AUTHOR]

Searching for effective porous materials with high loading capacity, low cost and high selectivity for the capture of C 2 H 2 from the gas mixtures is of great importance and a challenge task considering the industrial values of C 2 H 2 gas and the similar physicochemical properties of the gas mixtures. In the present study, a new metal-organic framework (MOF), namely {[Co(HCOO)(CPT)]·(DMF)(H 2 O)} (1) has been solvothermally synthesized by employ of the bifunctional linker 4-(4-carboxyphenyl)-1,2,4-triazole (HCPT) and the formate bridged metal-carboxylate-triazole secondary building units (SBUs), resulting in a three-dimensional (3D) framework with one-dimensional (1D) rhombic channels. Owing to the high-density formate decorated pore walls, the activated MOF shows a high uptake capacity toward C 2 H 2 (126.4 ​cm3/g at 298 ​K and 1 ​bar) and selectivity for C 2 H 2 over CO 2 (13.6 ​at 298 ​K and 1 ​bar), which has been further supported by the results of grand canonical Monte Carlo (GCMC) calculation simulations. A new MOF has been solvothermally synthesized by employ of the bifunctional linker 4-(4-carboxyphenyl)-1,2,4-triazole and the formate bridged chain-like secondary building units, which features a 3D framework with 1D rhombic channels. Owing to the formate decorated pore walls, the activated MOF shows high uptake capacity toward C 2 H 2 (126.4 ​cm3/g at 298 ​K and 1 ​bar) and selectivity for C 2 H 2 over CO 2 (13.6 ​at 298 ​K and 1 ​bar), which has been further supported by the results of GCMCcalculation simulations. [Display omitted] • A new porous Co(II)-MOF was prepared using the bifunctional ligand strategy. • This Co(II)-MOF shows a high C 2 H 2 /CO 2 selectivity at room temperature. • GCMC simulation results confirm the open O donor atoms serve as preferential binding sites for C 2 H 2. [ABSTRACT FROM AUTHOR]

Das Gerüst zeigt eine besonders starke Affinität für C SB 2 sb H SB 2 sb und die höchste IAST-Selektivität für die C SB 2 sb H SB 2 sb /CO SB 2 sb -Trennung unter den berichteten Adsorbentien. Keywords: C2H2/CO2 Separation; Electrostatic Potential; Hydrogen-Bonded Organic Framework EN C2H2/CO2 Separation Electrostatic Potential Hydrogen-Bonded Organic Framework 1 1 1 10/21/22 20221024 NES 221024 B Ein ultramikroporöses wasserstoffverbrücktes b organisches Gerüst mit passender Porenumgebung und Potenzialverteilung für C SB 2 sb H SB 2 sb wird von Zhangjing Zhang und Mitarbeitern in ihrer Zuschrift präsentiert (e202207579). C2H2/CO2 Separation, Hydrogen-Bonded Organic Framework, Electrostatic Potential. [Extracted from the article]

We constructed a robust microporous metal-organic framework (MUM-15) possessing two types of functionalized tri-mural nanotraps, in which elaborate nano-space and specific pore environment are beneficial to form pore confinement effect and multiple strong interactions for C 2 H 2. NUM-15 demonstrates not only remarkable sorption capacity for C 2 H 2 but also exhibits excellent separation performance for intractable C 2 H 2 /CO 2 and C 2 H 2 /C 2 H 4 mixtures. [Display omitted] • The strategy for constructing nanotraps was proposed and a novel MOF was successfully designed and synthesized. • The tailor-made tri-mural nanotraps provided pore confinement and synergetic multiple interaction sites for C 2 H 2. • Both high uptake capacity and strong affinity for C 2 H 2 were realized. • The MOF exhibits excellent separation ability for C 2 H 2 /CO 2 and C 2 H 2 /C 2 H 4 mixtures under ambient conditions. Considering the tremendous significance of purification and capture for acetylene (C 2 H 2) in the fields of manufacturing and the petrochemical industry, seeking appropriate materials with prominent performance is a crucial task and also remains an enduring challenge. To pursue this target, we report a robust microporous metal-organic framework (NUM-15) featuring two types of elaborate tri-mural nanotraps, in which fruitful nano-space confinement for accommodating gas molecules and multiple preferential adsorption sites providing multiple specific interactions with C 2 H 2 were supplied to form cooperative effect for efficient separation property. The NUM-15a (activated NUM-15) exhibits high loading for C 2 H 2 (3.5 mmol g−1) over carbon dioxide (CO 2) and ethylene (C 2 H 4) at 298 K and 1.0 bar and shows efficient separation performance for binary C 2 H 2 /CO 2 and C 2 H 2 /C 2 H 4 mixtures. The GCMC calculation revealed the crucial role of the multiple interactions in nanotraps for the selective capture of C 2 H 2. Under ambient conditions, dynamic breakthrough experiments revealed that NUM-15a demonstrates the enormous potential for actual industrial gas separation and is expected to be applied to the correlative industrial process. Both experiments and simulation calculations distinctly demonstrated that fabricating tri-mural nanotraps in MOFs is a feasible strategy for efficient C 2 H 2 capture and separation and provided a new route for exploiting high-performance materials for separation and purification technology. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) have been proven promising in addressing many critical issues related to gas separation and purification. However, it remains a great challenge to optimize the pore environment of MOFs for purification of specific gas mixtures. Herein, we report the rational construction of three isostructural microporous MOFs with the 4,4',4"-tricarboxyltriphenylamine (H 3 TCA) ligand, unusual hexaprismane Ni 6 O 6 cluster, and functionalized pyrazine pillars [PYZ-x, x = -H (DZU-10), -NH 2 (DZU-11), and -OH (DZU-12)], where the building blocks of Ni 6 O 6 clusters and huddled pyrazine pillars are reported in porous MOFs for the first time. These building blocks have enabled the resulting materials to exhibit good chemical stability and variable pore chemistry, which thus contribute to distinct performances toward C 2 H 2 /CO 2 separation. Both single-component isotherms and dynamic column breakthrough experiments demonstrate that DZU-11 with the PYZ-NH 2 pillar outperforms its hydrogen and hydroxy analogues. Density functional theory calculations reveal that the higher C 2 H 2 affinity of DZU-11 over CO 2 is attributed to multiple electrostatic interactions between C 2 H 2 and the framework, including strong C≡C···H-N (2.80 Å) interactions. This work highlights the potential of pore environment optimization to construct smart MOF adsorbents for some challenging gas separations.