The separation of ethane from its analogous ethylene is of great importance in the petrochemical industry, but very challenging and energy intensive. Adsorptive separation using CH-selective porous materials can directly produce high-purity CH in a single operation but suffers from poor selectivity. Here, we report an approach to boost the separation of CH over CH, involving the control of pore structures in two isoreticular ultramicroporous metal-organic framework (MOF) materials with weakly polar pore surface for strengthened binding affinity toward CH over CH. Under ambient conditions, the prototypical compound shows a very small uptake difference and selectivity for CH/CH, whereas its smaller-pore isoreticular analogue exhibits a quite large uptake ratio of 237% (60.0/25.3 cm cm), remarkably increasing the CH/CH selectivity. Neutron powder diffraction studies clearly reveal that the latter material shows self-adaptive sorption behavior for CH, which enables it to continuously maintain close van der Waals contacts with CH molecules in its optimized pore structure, thus preferentially binds CH over CH. Gas sorption isotherms, crystallographic analyses, molecular modeling, selectivity calculation, and breakthrough experiment comprehensively demonstrate this unique MOF material as an efficient CH-selective adsorbent for CH purification.

Highly selective adsorptive separation of olefin/paraffin through porous materials can produce high purity olefins in a much more energy-efficient way than the traditional cryogenic distillation. Here we report an ultramicroporous cobalt gallate metal–organic framework (Co-gallate) for the highly selective sieving separation of propylene/propane at ambient conditions. This material possesses optimal pore structure for the exact confinement of propylene molecules while excluding the slightly large propane molecules, as clearly demonstrated in the neutron diffraction crystal structure of Co-gallate⊃0.38C3D6. Its high separation performance has been confirmed by the gas sorption isotherms and column breakthrough experiments to produce the high purity of propylene (97.7%) with a high dynamic separation productivity of 36.4 cm3 cm–3 under ambient conditions. The gas adsorption measurement, pore size distribution, and crystallographic and modeling studies comprehensively support the high sieving C3H6/C3H8 separation in this MOF material. It is stable under different environments, providing its potential for the industrial propylene purification.

The removal of carbon dioxide (CO2) from acetylene (C2H2) is a critical industrial process for manufacturing high-purity C2H2. However, it remains challenging to address the tradeoff between adsorption capacity and selectivity, on account of their similar physical properties and molecular sizes. To overcome this difficulty, here we report a novel strategy involving the regulation of a hydrogen-bonding nanotrap on the pore surface to promote the separation of C2H2/CO2 mixtures in three isostructural metal–organic frameworks (MOFs, named MIL-160, CAU-10H, and CAU-23, respectively). Among them, MIL-160, which has abundant hydrogen-bonding acceptors as nanotraps, can selectively capture acetylene molecules and demonstrates an ultrahigh C2H2 storage capacity (191 cm3 g–1, or 213 cm3 cm–3) but much less CO2 uptake (90 cm3 g–1) under ambient conditions. The C2H2 adsorption amount of MIL-160 is remarkably higher than those for the other two isostructural MOFs (86 and 119 cm3 g–1 for CAU-10H and CAU-23, respectively) under the same conditions. More importantly, both simulation and experimental breakthrough results show that MIL-160 sets a new benchmark for equimolar C2H2/CO2 separation in terms of the separation potential (Δq break = 5.02 mol/kg) and C2H2 productivity (6.8 mol/kg). In addition, in situ FT-IR experiments and computational modeling further reveal that the unique host–guest multiple hydrogen-bonding interaction between the nanotrap and C2H2 is the key factor for achieving the extraordinary acetylene storage capacity and superior C2H2/CO2 selectivity. This work provides a novel and powerful approach to address the tradeoff of this extremely challenging gas separation.

Separating acetylene from carbon dioxide is important but highly challenging owing to their similar physical properties and molecular dimensions. Herein, we report highly efficient electrostatically driven CO2/C2H2 separation in an ultramicroporous cadmium nitroprusside (Cd‐NP) with compact pore space and complementary electrostatic potential well fitting for CO2, thus enabling molecular quadrupole moment recognition of CO2 over C2H2. This material shows a high CO2/C2H2 uptake ratio of 6.0 as well as remarkable CO2/C2H2 selectivity of 85 under ambient conditions with modest CO2 heat of adsorption. Neutron powder diffraction experiments and molecular simulations revealed that the electrostatic potential compatibility between pore structure and CO2 allows it to be trapped in a head‐on orientation towards the Cd center, whereas the diffusion of C2H2 is electrostatically forbidden. Dynamic breakthrough experiments have validated the separation performance of this compound for CO2/C2H2 separation.

Temperature sensors play as ignificant role in biology,c hemistry,a nd engineering, especially those that can work accurately in anoninvasive manner.Weadopted aphotoinduced post-synthetic copolymerization strategy to realize amembranous ratiometric luminescent thermometer based on the emissions of two lanthanide ions.T his novel mixedlanthanide polyMOF membrane exhibits not only the integrity and temperature sensing behaviour of the Ln-MOF powder but also excellent mechanical properties,s uch as flexibility, elasticity,a nd processability.M oreover,t he polyMOF membrane shows remarkable stability under harsh conditions, including high humidity,s trong acid and alkali (pH 0-14), which allowed the mapping of temperature distributions in extreme circumstances.T his work highlights as imple strategy for polyMOF membrane formation and pushes forwardt he further practical application of Ln-MOF-based luminescent thermometers in various fields and conditions.

A terbium (iii) lanthanide–organic framework provides a platform for a recyclable multi-responsive luminescent sensor for detecting Fe3+, MnO4−, Cr2O72−, and p-nitrotoluene (4-NT), which is the first reported MOF-based sensor for detecting explosive 4-NT.

A highly chemically and thermally stable mesoporous hydrogen-bonded organic framework with a high surface area and a large pore volume has been rationally designed and constructed.

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