A 2D metal–thiacalix[4]arene porous coordination polymer with 1D channels: gas absorption/separation and frequency response

Abstract

A 2D layered structure {[Co₄(TC4A)Cl](L)₂][(CH₃CH₂)₄N]}_n (+solvent)(1) has been solvothermally synthesized by assembly of Co₄-TC4A (H₄TC4A = p-tert-butylthiacalix[4]arene) subunits and L (H₂L = 4-(1H-tetrazol-5-yl)benzoic acid) ligands. The layers arranged in an edge-to-edge (AAAA) manner, which represented the only example of 2D porous coordination polymers (PCPs) with 1D uniform channels of metal–thiacalix[4]arene. The activated PCP 1 exhibited high selectivity for C₃H₈/C₂H₆, C₃H₆/C₂H₄, and C₃H₈/C₂H₄, which makes it a competitive porous material for C₃/C₂ alkane and/or olefin separations. Frequency response investigations for C₃H₈ and C₂H₆ indicated that the 1D channels and inter-layer voids of the activated crystalline samples are primarily responsible for the observed gas adsorption and separation performances.