Five Novel Silver-Based Coordination Polymers as Photoluminescent Sensing Platforms for the Detection of Nitrobenzene

Nitrobenzene (NB) is a highly toxic chemical and a cause for concern to human health and the environment. Hence, it is worth designing new efficient and robust sensing platforms for NB. In this study, we present three newly synthesized luminescent silver cluster-based coordination polymers, {[Ag-10(StBu)(6)(CF3COO)(4)(hpbt)] (DMAc)(2)(CH3CN)(2)}(n) (hpbt= N,N,N',N'N",N"-hexa(pyridine-4-yl)benzene-1,3,5-triamine), [Ag-12(StBu)(6)(CF3COO)(6)(bpva)(3)](n) (bpva= 9,10-Bis(2-(pyri-din-4-yl)vinyl)anthracene), and {[Ag-12(StBu)(6)(CF3COO)(6)(bpb)(DMAc)(2)(H2O)(2)] (DMAc)(2)}(n) (bpb= 1,4-Bis(4-pyridyl)benzene) composed of Ag-10, Ag-12 and Ag-12 cluster cores, respectively, connected by multidentate pyridine linkers. In addition, two new luminescent polymorphic silver(I)-based coordination polymers, [Ag-(CF3COO)(dpa)](n) (dpa= 9,10-di(4-pyridyl)anthracene) referred to as Agdpa (H) and Agdpa (R), where H and R denote hexagon- and rod-like crystal shapes, respectively, have been prepared. The coordination polymers exhibit highly sensitive luminescence quenching effects to NB, attributed to the pi-pi stacking interactions between the polymers and NB as well as the electron-withdrawing character of NB.