Unique Cluster-Metal Framework Constructed by Multidentate N-Donating Ligand for TNP Detection

Abstract

Multidentate organic ligand with bridged and chelated functions is firstly developed to build cluster-based metal–organic framework. N-donating multidentate ligand 4-phenyl-2,6-bis(2′-pyrazinyl)pyridine (PBPP) is deliberately selected to construct a unique metal–organic framework {[WS4Cu4I4[Ni(PBPP)2]]2·DMF]}n (1) (DMF = N,N′-dimethylformamide). X-ray structure analysis reveals that 1 exhibits a 2D (6,3) graphene-like network, fabricated by rare pentanuclear [WS4Cu4]2+ building clusters, Ni2+ building metals, bridged and chelated PBPP and terminal I−. 1 has good water stability and luminescence. More importantly, the detection performance of 1 is explored through luminescence quenching effect, which reveals that 1 can detect 2,4,6-trinitrophenol (TNP) with high sensitivity and selectivity. The sensing mechanism has also been studied.