Facile fabrication of Ag2(bdc)@Ag nano-composites with strong green emission and their response to sulfide anion in aqueous medium

Abstract A novel composites constructed MOF(s) and Ag nanoclusters, Ag 2 (bdc)@Ag (H 2 bdc is 1, 4-benzenedicarboxylate) have been simply fabricated through solution strategy for the first time, and characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy(XPS). The as-prepared composites were found to be an effective material for the selective fluorescence detection of microgram levels of S 2− in aqueous solution based on fluorescence quenching effects. Under optimized experimental conditions, the probe exhibited a stable response for S 2– over a concentration range from 0.2 μM to 30 μM and a detection limit of 0.21 μM. The feasibility of the proposed method was further demonstrated through the detection of S 2– in real samples, with the satisfactory recoveries in the range of 97.8–101.9%. The possible sensing quenching mechanism for the detection of S 2– could be attributed to the formation of Ag 2 S during the addition of S 2– into the Ag 2 (bdc)@Ag dispersion system. The proposed method for the detection of S 2– has potential application in the environmental pollutant analysis.