A Water-Stable Cl@Ag14 Cluster Based Metal–Organic Open Framework for Dichromate Trapping and Bacterial Inhibition

Decoding the principles of cluster-based framework assembly at the molecular level remains a persistent challenge. Herein, we isolated and characterized a novel water-stable three-dimensional (3D) metal–organic open framework [Cl@Ag14(cPrCC)10Cl2·(p-TOS)·1/3H2O] n (SD/Ag14, cPrCCH = cyclopropylacetylene; p-TOS = p-toluenesulfonate), which contains a chloride-templated Ag14 cluster as building block. For SD/Ag14, one chloride acts as the template to shape the Ag14 cluster and the other bridges the clusters to a 3D pcu-h open framework. As revealed by high resolution electrospray mass spectrometry (HRESI-MS), the Ag12–Ag14 species are potential cluster-based intermediates to the 3D pcu-h framework, which authenticates a preconceived idea that the 3D framework is hierarchically assembled from the silver clusters as observed in solid state. Interestingly, SD/Ag14 can be used effectively to remove the environmental pollutant Cr2O7 2– from wastewater through anion exchange in a single-crystal-to-single-crystal (SC–SC) transformation fashion. Furthermore, SD/Ag14 exhibits excellent antibacterial activity against Staphylococcus aureus, thus making it a potential antibacterial agent.