Ethylene production from C2 hydrocarbon mixtures through one separation step is desirable but challenging because of the similar size and physical properties of acetylene, ethylene, and ethane. Herein, we report three new isostructural porous coordination networks (NPU-1, NPU-2, NPU-3; NPU represents Northwestern Polytechnical University) that are sustained by 9-connected nodes based upon a hexanuclear metal cluster of composition [Mn₆(μ₃-O)₂(CH₃COO)₃]⁶⁺. NPU-1/2/3 exhibit a dual cage structure that was systematically fine-tuned in terms of cage size to realize selective adsorption of C₂H₂ and C₂H₆ over C₂H₄. Dynamic breakthrough experiments demonstrated that NPU-1 produces ethylene in >99.9% purity from a three-component gas mixture (1:1:1 C₂H₂/C₂H₄/C₂H₆). Molecular modeling studies revealed that the dual adsorption preference for C₂H₂ and C₂H₆ over C₂H₄ originates from (a) strong hydrogen-bonding interactions between electronegative carboxylate O atoms and C₂H₂ molecules in one cage and (b) multiple non-covalent interactions between the organic linkers of the host network and C₂H₆ molecules in the second cage.

In this work, we report the facile synthesis of a hollow ZnNiC nano-box using a hollow ZnNi-MOF as the sacrificial template through a one-step pyrolysis process. Remarkably, the as-prepared hollow ZnNiC/paraffin composite exhibited a minimum reflection loss (RL_min) of −66.1 dB at 15.3 GHz and effective absorption bandwidth of 4.4 GHz with a thickness of 1.6 mm.

Transition metal oxides (TMOs) are promising materials for supercapacitors (SCs) because of their high theoretical capacity. However, their finite active sites and poor electrical conductivity lead to reluctant electrochemical performance. Herein, we report a facile electrochemical activation (ECA) method to boost the electrochemical activity of Ni‐Co oxide nanosheet arrays (NiCoO NSA) for SCs. Specifically, honeycomb‐like NiCoO NSA that was made through a solvothermal method followed by air annealing was activated by simply exerting certain cyclic voltammetry scans (the activated sample is named ac‐NiCoO NSA). We have found this treatment results in dramatic surface structure change, forming numerous sub‐nanostructures (nanoparticles and nano‐leaves) on the NiCoO nanosheets. Rich antisite defects and oxygen vacancies in the NiCoO spinel phase were also created by the ECA treatment. Consequently, the ac‐NiCoO NSA delivered a maximum capacity of 206.5 mAh g⁻¹ (0.5 A g⁻¹), which is about three times of the NiCoO NSA without treatment. A hybrid SC based on the ac‐NiCoO NSA demonstrated excellent energy storage capacity (power density of 17.3 kW kg⁻¹ and energy density of 45.4 Wh kg⁻¹) and outstanding cyclability (>20,000 cycles, 77.4% retention rate). Our method provides a simple strategy for fabricating high performance TMOs for electrical energy storage devices like SCs.