Multipoint Interactions Enhanced CO2 Uptake: A Zeolite-like Zinc-Tetrazole Framework with 24-Nuclear Zinc Cages

A zeolite-like microporous tetrazole-based metal organic framework (MOF) with 24 nuclear zinc cages was synthesized and characterized. It exhibits high CO2 adsorption capacity up to 35.6 wt % (8.09 mmol/g) and excellent CO2/CH4 selectivity at 273 K/1 bar, being among the highest values known to date. Theoretical calculations based on simulated annealing techniques and periodic DFT revealed that CO2 is predominantly located around the inner surface of the cages through multipoint interactions, in particular, around the aromatic tetrazole rings. Importantly, it is the first time that multipoint interactions between CO2 molecules and frameworks resulting in high CO2 uptake are observed.