Made in Water: A Stable Microporous Cu(I)-carboxylate Framework (CityU-7) for CO₂, Water, and Iodine Uptake

Using water as the sole solvent, the bifunctional molecule tetrakis(methylthio)-1,4-benzenedicarboxylic acid (TMBD) was reacted with Cu(CH₃CN)₄BF₄ to form a robust microporous metal-organic framework (MOF, CityU-7) featuring Cu(I) ions being simultaneously bonded to the carboxyl and thioether donors. The MOF solid is stable in air and can be easily activated by heating, without the need for treatment with organic solvents. The subnanoscopic pores (ca. 0.6 nm) of the host net allow for uptake of CO₂ and H₂O but exhibit lesser sorption for N₂ at 77 K. The microporous net can also be penetrated by I₂ molecules.