An AIE-active tetraphenylethene functionalized silver-tetrazolate coordination polymer for selective fluorescence sensing of explosives

Abstract

An aggregation-induced emission (AIE)-active and highly coordinated polytetrazole luminogen was designed and synthesized by combining four tetrazole units with tetraphenylethylene (TPE), i.e. tetrakis[4-(1H-tetrazol-5-yl)phenyl]ethylene (H₄ttazpe) which is weakly emissive in dilute solution and becomes highly luminescent in the aggregated state. Coordination self-assembly of a TPE-based multidentate tetrazole ligand with silver(I) ions can afford a unique fluorescent coordination polymer with (3,6)-connected rtl topology of [Ag(H₃ttazpe)] in the cluster representation, in which H₃ttazpe⁻ serves as the first tetrakistetrazole ligand with a tetra-coordinating bridging mode. We demonstrate, for the first time, the use of the luminescent metal–organic framework (LMOF) with TPE as the core surrounded by four peripheral tetrazole groups for fast and sensitive florescence-based nitro-explosive detection in aqueous media.