Synthesis of fluorescent probe containing a ferrocenyl Schiff base by proline ionic liquid and its application to the detection of Cr 2 O 7 2-and CrO 4 2-

This paper describes the design and synthesis of the Probe O, a small organic molecule. Proline ionic liquid was used as the catalyst, which is environmentally friendly and can be recycled many times. In the practical application, the ability of the Probe O for the detection of Cr 2 O 7 2- and CrO 4 2- was investigated. It was found that Probe O could specifically identify Cr 2 O 7 2- and CrO 4 2- without interference from other anions and was almost independent of pH and time by fluorescence and UV spectra. The quenching constants (K sv ) and the limit of detection (LOD) of O-Cr 2 O 72- and O-CrO 4 2- were calculated. The binding of Probe O to CrO 4 2- was 1:1 and Probe O to Cr 2 O 7 2- was 2:1 by MS, and the possible mechanisms of O-CrO 4 2- and O-Cr 2 O 72- were deduced by 1 H NMR and IR titration.