A microporous Zn(II)-MOF with open metal sites: structure and selective adsorption properties

A three-dimensional microporous framework, Zn(II)-MOF [Zn(HPyImDC)(DMA)](n) (1) (H(3)PyImDC = 2-(pyridine- 4-yl)-1H-4,5-imidazoledicarboxylic, DMA = N, N'-dimethylacetamide), with open metal sites and small-sized pores, exhibits excellent selective capture of CO2 over N-2 and CH4 at 273 K, as well as alcohols from water. The excellent CO2 adsorption selectivity of 1 allows its potential use in the capture of CO2 from industrial flue gas or the removal of CO2 from natural gas. More interestingly, compound 1 represents the rare case of porous materials separating propanol isomers, which may be caused by the relative flexibility of the linear n-propanol considering that both n-propanol and i-propanol have similar kinetic diameters.