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Elaborately designed multifunctional electrocatalysts capable of promoting Li+ and CO2 transport are essential for upgrading the cycling stability and rate capability of Li‐CO2 batteries. Hydrogen‐bonded organic frameworks (HOFs) with open channels and easily functionalized surfaces hold great potential for applications in efficient cathodes of Li‐CO2 batteries. Herein, a robust HOFS (HOF‐FJU‐1) is introduced for the first time as a co‐catalyst in the cathode material of Li‐CO2 batteries. HOF‐FJU‐1 with cyano groups located periodically in the pore can induce homogeneous deposition of discharge products and accommodate volumetric expansion of discharge products during cycling. Besides, HOF‐FJU‐1 enables effective interaction between Ru0 nanoparticles and cyano groups, thus forming efficient and uniform catalytic sites for CRR/CER. Moreover, HOF‐FJU‐1 with regularly arranged open channels are beneficial for CO2 and Li+ transport, enabling rapid redox kinetic conversion of CO2. Therefore, the HOF‐based Li‐CO2 batteries are capable of stable operation at 400 mA g−1 for 1800 h and maintain a low overpotential of 1.96 V even at high current densities up to 5 A g−1. This work provides valuable guidance for developing multifunctional HOF‐based catalysts to upgrade the longevity and rate capability of Li‐CO2 batteries. [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]

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]

The separation of propylene (C3H6) and propane (C3H8) is of great significance in the chemical industry, which poses a challenge due to their almost identical kinetic diameters and similar physical properties. In this work, we synthesized an ultramicroporous flexible hydrogen‐bonded organic framework (named HOF‐FJU‐106) by using molecule 2,3,6,7‐tetra (4‐cyanophenyl) tetrathiafulvalene (TTF‐4CN). The formation of the dimer causes the TTF‐4CN molecular to bend and weaken π‐stacked interactions, coupled with the flexibility of C≡N ⋯ ${\cdots }$ H−C hydrogen bonds, which leads to reversible conversion between open and closed frameworks through the mutual slip of adjacent layers/columns under activation and stimulation of gas molecules. Through gas adsorption isotherms and adsorption enthalpy, HOF‐FJU‐106a exhibited adaptive adsorption and stronger binding affinity for C3H6, and presented a recorded gas uptake ratio of C3H6/C3H8 (23.77) among presentative HOF materials at room temperature to date. Importantly, the flexible HOF‐FJU‐106a shows an interesting phenomenon about the reversible gate pressure control under variable temperature, which realized the gas adsorption and separation performance enhancement for the binary C3H6/C3H8 mixtures. This strategy through designing HOFs with thermoregulatory gating effect is a powerful way to maximize the performance of materials. [ABSTRACT FROM AUTHOR]