Highly sensitive and selective chemosensor for Cu2+ based on a Schiff base

A new chemosensor based on a Schiff base has been designed and synthesized. Its sensing behavior toward various metal ions was investigated by fluorescence and UV-Vis spectroscopic methods. The fluorescence of the sensor was quenched and the color rapidly changed from canary yellow to brown after the addition of Cu2+, while no changes occurred after the addition of other metal ions, which contributes to the detection of Cu2+ with naked eyes. The fluorescence quantum yield of the ligand was calculated to be 0.52. The corresponding detection limit of Cu2+ was 5.721×10−7 mol/L, and the 1:1 binding mode of the sensor with Cu2+ was revealed by Job’s plot.