A multifunctional cadmium–organic framework comprising tricarboxytriphenyl amine: selective gas adsorption, liquid-phase separation and luminescence sensing

Abstract

The reaction of tricarboxytriphenyl amine (H₃TCA) with Cd^II and auxiliary ligand 4,4′-bis(1-imidazolyl)biphenyl (bimb) afforded [Cd₃(TCA)₂(bimb)·(DMA)₆]_n (1) containing a two-fold interpenetrating three-dimensional microporous framework. Compound 1 showed remarkable adsorption enthalpies for CO₂ and H₂ and good H₂/N₂ selectivity at low temperature. Moreover, activated 1 showed a highly selective adsorption towards CO₂ over N₂ and CH₄ under ambient conditions. Interestingly, compound 1 selectively removed methyl orange (MO) over methylene blue (MB) from contaminated water with good recyclability, and possessed the second highest adsorption capacity for MO among the MOFs reported to date. Remarkably, complex 1 showed strong guest-dependent luminescence behavior.