Supramolecular porous architectures
We explore an original approach towards microporous architectures using ionic hydrogen bonding as linkage for 3D opened-structures. These architectures, named SPA, are prepared under mild conditions in aqueous medium using H-bond donor, typically protonated poly-pyridinic molecules, and anionic metal-oxalate complex as acceptor of H-bonds (illustration).
Robustness of ionic H-bond allows modification of R function of the organic part while keeping same supramolecular assembly.
In this way, channels walls is covered by chemical functions modulating characteristics and sorption affinities of the materials. For example, SPA-2 functionalized with pyridine groups (blue spheres in illustration) can trap acidic molecules. Same approach can be applied to capture of noble metal ions.
Illustration: Tri-pyridinic derivatives and opened architectures SPA-1(R) and SPA-2(OPy) obtained with association of [Al(oxalate)3]3- and [Zr2(oxalate)7]6-, respectively.