Dual-mode luminescence and colorimetric sensing for Al and Fe/Fe ions in water using a zinc coordination polymer.

A zinc(II) coordination polymer, [Zn(Hdhtp)(2,2'-bpy)(HO)] (1), has been utilized as a dual-mode luminescence-colorimetric sensor (Hdhtp = 2,5-dihydroxy terephthalate and 2,2'-bpy = 2,2'-bipyridine). The presence of hydroxyl groups in Hdhtp can promote excited-state intra- and intermolecular proton transfer (ESIPT) phenomena. Therefore, compound 1, which displays high stability in aqueous environments, exhibits a strong green-yellow photoluminescence.