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Developing hydrogen‐bonded organic frameworks (HOFs) that combine functional sites, size control, and storage capability for targeting gas molecule capture is a novel and challenging venture. However, there is a lack of effective strategies to tune the hydrogen‐bonded network to achieve high‐performance HOFs. Here, a series of HOFs termed as HOF‐ZSTU‐M (M=1, 2, and 3) with different pore structures are obtained by introducing structure‐directing agents (SDAs) into the hydrogen‐bonding network of tetrakis (4‐carboxyphenyl) porphyrin (TCPP). These HOFs have distinct space configurations with pore channels ranging from discrete to continuous multi‐dimensional. Single‐crystal X‐ray diffraction (SCXRD) analysis reveals a rare diversity of hydrogen‐bonding models dominated by SDAs. HOF‐ZSTU‐2, which forms a strong layered hydrogen‐bonding network with ammonium (NH4+) through multiple carboxyl groups, has a suitable 1D "pearl‐chain" channel for the selective capture of propylene (C3H6). At 298 K and 1 bar, the C3H6 storage density of HOF‐ZSTU‐2 reaches 0.6 kg L−1, representing one of the best C3H6 storage materials, while offering a propylene/propane (C3H6/C3H8) selectivity of 12.2. Theoretical calculations and in situ SCXRD provide a detailed analysis of the binding strength of C3H6 at different locations in the pearl‐chain channel. Dynamic breakthrough tests confirm that HOF‐ZSTU‐2 can effectively separate C3H6 from multi‐mixtures. [ABSTRACT FROM AUTHOR]

Developing hydrogen‐bonded organic frameworks (HOFs) that combine functional sites, size control, and storage capability for targeting gas molecule capture is a novel and challenging venture. However, there is a lack of effective strategies to tune the hydrogen‐bonded network to achieve high‐performance HOFs. Here, a series of HOFs termed as HOF‐ZSTU‐M (M=1, 2, and 3) with different pore structures are obtained by introducing structure‐directing agents (SDAs) into the hydrogen‐bonding network of tetrakis (4‐carboxyphenyl) porphyrin (TCPP). These HOFs have distinct space configurations with pore channels ranging from discrete to continuous multi‐dimensional. Single‐crystal X‐ray diffraction (SCXRD) analysis reveals a rare diversity of hydrogen‐bonding models dominated by SDAs. HOF‐ZSTU‐2, which forms a strong layered hydrogen‐bonding network with ammonium (NH4+) through multiple carboxyl groups, has a suitable 1D "pearl‐chain" channel for the selective capture of propylene (C3H6). At 298 K and 1 bar, the C3H6 storage density of HOF‐ZSTU‐2 reaches 0.6 kg L−1, representing one of the best C3H6 storage materials, while offering a propylene/propane (C3H6/C3H8) selectivity of 12.2. Theoretical calculations and in situ SCXRD provide a detailed analysis of the binding strength of C3H6 at different locations in the pearl‐chain channel. Dynamic breakthrough tests confirm that HOF‐ZSTU‐2 can effectively separate C3H6 from multi‐mixtures. [ABSTRACT FROM AUTHOR]

Methane (CH 4) purification using energy-efficient separation technology is important for the economic and safety of natural gas refining. Meanwhile, the common impurity acetylene (C 2 H 2) was also served as raw material to produce various organic products, therefore the highly efficient purification of CH 4 and C 2 H 2 are very important and challenging. Herein, we demonstrate the separation ability of HOF-16 for C 2 H 2 /CH 4 and CO 2 /CH 4 mixtures in detail. HOF-16 has a potential affinity for C 2 H 2 capture, resulting from the exposed free –COOH sites in the suitable pore channel. Gas sorption isotherms reveal that HOF-16a creates a high C 2 H 2 /CH 4 uptake ratio of 7.9 at 298 K and 1 bar, resulting in a C 2 H 2 /CH 4 separation selectivity of 107 (50/50, v/v) under ambient conditions, which is a record value among HOFs and even exceeds many MOFs. Theoretical calculations confirm that the free –COOH sites in the HOF-16a channel provide additional interactions for the C 2 H 2 molecules. Dynamic breakthrough experiments indicate that C 2 H 2 could be highly selective removed from C 2 H 2 /CH 4 (1/99, v/v) mixture. Combined with the low isosteric heat of adsorption (Q st), HOF-16a can efficiently extract C 2 H 2 from the adsorption bed and purify CH 4 into high purity (>99.9%) with low energy consumption. HOF-16 for separating C 2 H 2 /CH 4 gas mixture into high purity gas. [Display omitted] • HOF-16 was synthesized and has free –COOH after activation. • Activated phase HOF-16a has a suitable pore size and a polar pore environment. • HOF-16a exhibits C 2 H 2 /CH 4 selectivity of 107 and C 2 H 2 /CH 4 uptake ratio of 6.9. • HOF-16a can efficiently separate C 2 H 2 /CH 4 mixture in one sorption-desorption cycle. [ABSTRACT FROM AUTHOR]