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Comprehensive Summary: Carbon dioxide (CO2) capture is one of the most important aspects of reducing global warming. In terms of CO2 capture, metal‐organic frameworks (MOFs) have several advantages. However, it isn't easy to shape MOFs while maintaining their performance. Herein, we describe the development of a pellet‐shaped ultramicroporous MOF, Ni(3‐ain)2 (3‐ain = 3‐aminoinoisonicotinic acid), that is capable of selectively adsorbing CO2. Polyvinyl butyral (PVB) is used as a binder during the production of Ni(3‐ain)2 MOF pellets. The adequately shaped material can maintain its crystallinity and exhibit a high CO2 adsorption capacity (3.73 mmol·g–1) at ambient conditions, which is significantly greater than those obtained for N2 (0.63 mmol·g–1) and CO (0.90 mmol·g–1). Consequently, this material displays high IAST selectivities for CO2/N2 (26.3, 15/85, V/V) and CO2/CO (19.2, 1/99, V/V). According to the theoretical calculations, Ni(3‐ain)2 preferentially adsorbs CO2 molecules over N2 molecules and CO molecules. The results of experiments on dynamic breakthrough have demonstrated that Ni(3‐ain)2 pellets are capable of effectively separating CO2/N2 or CO2/CO mixtures under conditions of dynamic flow. Furthermore, the structured MOF materials can be synthesized in one step at kilogram scale. This work provides an avenue for the shaping of MOFs for potential industrial applications in the future. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Carbon dioxide (CO2) capture is one of the most important aspects of reducing global warming. In terms of CO2 capture, metal‐organic frameworks (MOFs) have several advantages. However, it isn't easy to shape MOFs while maintaining their performance. Herein, we describe the development of a pellet‐shaped ultramicroporous MOF, Ni(3‐ain)2 (3‐ain = 3‐aminoinoisonicotinic acid), that is capable of selectively adsorbing CO2. Polyvinyl butyral (PVB) is used as a binder during the production of Ni(3‐ain)2 MOF pellets. The adequately shaped material can maintain its crystallinity and exhibit a high CO2 adsorption capacity (3.73 mmol·g–1) at ambient conditions, which is significantly greater than those obtained for N2 (0.63 mmol·g–1) and CO (0.90 mmol·g–1). Consequently, this material displays high IAST selectivities for CO2/N2 (26.3, 15/85, V/V) and CO2/CO (19.2, 1/99, V/V). According to the theoretical calculations, Ni(3‐ain)2 preferentially adsorbs CO2 molecules over N2 molecules and CO molecules. The results of experiments on dynamic breakthrough have demonstrated that Ni(3‐ain)2 pellets are capable of effectively separating CO2/N2 or CO2/CO mixtures under conditions of dynamic flow. Furthermore, the structured MOF materials can be synthesized in one step at kilogram scale. This work provides an avenue for the shaping of MOFs for potential industrial applications in the future. [ABSTRACT FROM AUTHOR]

In the electronics industry, the efficient recovery and capture of sulfur hexafluoride (SF6) from SF6/N2 mixtures is of great importance. Herein, three metal–organic frameworks with fine‐tuning pore structures, Cu(peba)2, Ni(pba)2, and Ni(ina)2, were designed for SF6 capture. Among them, Ni(ina)2 has perfect pore sizes (6 Å) that are comparable to the kinetic diameter of sulfur hexafluoride (5.2 Å), affording the benchmark binding affinity for SF6 gas. Ni(ina)2 exhibits the highest SF6/N2 selectivity (375.1 at 298 K and 1 bar) and ultra‐high SF6 uptake capacity (53.5 cm3 g−1 at 298 K and 0.1 bar) at ambient conditions. The remarkable separation performance of Ni(ina)2 was verified by dynamic breakthrough experiments. Theoretical calculations and the SF6‐loaded single‐crystal structure provided critical insight into the adsorption/separation mechanism. This porous coordination network has the potential to be used in industrial applications. [ABSTRACT FROM AUTHOR]

Perfluorocarbons (PFCs) such as CF 4 , C 2 F 6, and C 3 F 8 , are extensively used in the microelectronics and semiconductor industries, yet their global warming potentials—thousands of times greater than that of CO₂—underscore the urgent need for effective mitigation strategies. While converting PFCs into non-PFCs offers a method for their destruction, a more sustainable approach lies in the recovery and recycling of these compounds using advanced adsorbents. This review explores the potential of cutting-edge porous materials, including metal-organic frameworks (MOFs), covalent-organic frameworks (COFs), and porous organic cages (POCs), for the adsorption and separation of PFCs. By precisely tuning pore sizes and chemical environments through modifications of metal ions and ligands, these porous adsorbents can be tailored to exhibit specific adsorption and separation capabilities. The review focuses on the selective separation of PFCs from nitrogen and other fluorinated gases, with particular emphasis on the latest advancements in adsorbents designed to differentiate between PFCs and other fluorinated compounds in the presence of nitrogen. [Display omitted] • Advanced porous adsorbents such as MOFs, COFs, and POCs are effective in capturing PFC greenhouse gasses. • Functionalized MOFs show good selectivity and adsorption capacity for PFC. • Fluorinated POCs have high fluorine‑fluorine interactions, which improves CF 4 capture. • Challenges include scaling synthesis processes and testing adsorbents in real-world settings. [ABSTRACT FROM AUTHOR]

The enrichment and purification of coal‐bed methane provides a source of energy and helps offset global warming. In this work, we demonstrate a strategy involving the regulation of the pore size and pore chemistry to promote the separation of CH4/N2 mixtures in four nickel‐based coordination networks, named Ni(ina)2, Ni(3‐ain)2, Ni(2‐ain)2, and Ni(pba)2, (where ina=isonicotinic acid, 3‐ain=3‐aminoisonicotinic acid, 2‐ain=2‐aminoisonicotinic acid, and pba=4‐(4‐pyridyl)benzoic acid). Among them, Ni(ina)2 and Ni(3‐ain)2 can effectively separate CH4 from N2 with top‐performing performance because of the suitable pore size (≈0.6 and 0.5 nm) and pore environment. Explicitly, Ni(ina)2 exhibits the highest ever reported CH4/N2 selectivity of 15.8 and excellent CH4 uptake (40.8 cm3 g−1) at ambient conditions, thus setting new benchmarks for all reported MOFs and traditional adsorbents. The exceptional CH4/N2 separation performance of Ni(ina)2 is confirmed by dynamic breakthrough experiments. Under different CH4/N2 ratios, Ni(ina)2 selectively extracts methane from the gaseous blend and produces a high purity of CH4 (99 %). Theoretical calculations and CH4‐loading single‐crystal structure analysis provide critical insight into the adsorption/separation mechanism. Ni(ina)2 and Ni(3‐ain)2 can form rich intermolecular interactions with methane, indicating a strong adsorption affinity between pore walls and CH4 molecules. Importantly, Ni(ina)2 has good thermal and moisture stability and can easily be scaled up at a low cost ($25 per kilogram), which will be valuable for potential industrial applications. Overall, this work provides a powerful approach for the selective adsorption of CH4 from coal‐bed methane. [ABSTRACT FROM AUTHOR]

• Through the use of crystal engineering, two new MOF materials were designed and synthesized. • Ni(3-mpba) 2 has both excellent SF 6 /N 2 selectivity (2 2 1) and remarkable SF 6 uptake capacity (63.4 cm3g−1) at 298 K and 100 kPa. • Trace amounts of sulfur hexafluoride can be effectively captured under ambient conditions. • Excellent thermal and chemical stability. The capture and separation of sulfur hexafluoride (SF 6) from nitrogen (N 2) has the potential to reduce greenhouse gas emissions and provide economic benefits to the semiconductor industry. Herein, a series of metal–organic frameworks (MOFs) with different pore environments (Ni(pba) 2 (pba = 4-(4-pyridyl)benzoate), Ni(3-mpba) 2 (3-mpba = 3-methyl-4-(4-pyridyl)benzoate), and Co(3-mpba) 2) were designed and synthesized for SF 6 /N 2 separation. The most promising candidate is Ni(3-mpba) 2 , which exhibits excellent SF 6 uptake capacity (63.4 cm3 g−1 at 298 K and 100 kPa) and the highest SF 6 /N 2 selectivity (221 at 298 K and 100 kPa). X-ray diffraction analysis and theoretical calculations indicate that introducing the methyl group into Ni(3-mpba) 2 alters the microchemical environment of the pores. Ni(3-mpba) 2 has a smaller pore structure and more binding sites than Ni(pba) 2 ; its structure and binding sites enhance the affinity between sulfur hexafluoride and the adsorbent. Dynamic breakthrough experiments further verify the remarkable separation performance of Ni(3-mpba) 2 under simulated actual working conditions. In combination with its excellent regeneration ability and cycling performance, this porous coordination network shows great promise for SF 6 /N 2 separation. [ABSTRACT FROM AUTHOR]