Novel dual ligands capped perovskite quantum dots for fluoride detection

Organolead halide perovskite quantum dots (PQDs) have attracted emerging attention due to their high quantum yield and tremendous potential for lighting and display technology. However, monotonous ligands impede their application, especially in analytical chemistry. In this paper, we have developed a novel dual-ligand strategy to facilely synthesize fluoride-responded CH 3 NH 3 PbBr 3 PQDs which employ n -Octylamine (OA) and 6-amino-1-hexanol (AH) as two capping ligands. The usual ligand, OA, stabilizes the PQDs emitting intense fluorescence; the new introduced ligand, AH, could interact with fluoride through hydrogen bonding between hydroxyl group and fluoride, leading to the growth and fluorescence quenching of the PQDs. This original fluorescent nanosensor was successfully applied to the detection of fluoride with high sensitivity and excellent selectivity. The limit of detection was down to 3.2 μM (0.061 mg/L) and quite lower than the WHO guideline. Spot plate test indicated that the nanosensor could also be used for visual detection of fluoride.