文摘
A new dual chemosensor (TTF-PBA) for Fe3+ and Cu2+ in different signal pathways was designed and synthesized. The absorption spectrum, fluorescence spectrum and cyclic voltammograms changed in the presence of Cu2+ and Fe3+. The optical color changed within 5 s from yellow to orange upon the addition of Cu2+, and it changed to dark yellow when Fe3+ existed. The cyclic voltammogram of Cu2+/TTF-PBA changed from Eox = 0.50 V, Ered = 0.32 V to Eox = 0.64 V, Ered = 0.80 V (vs Ag/AgCl) upon the addition of 2.0 equiv. Cu2+. As for Fe3+/TTF-PBA, its oxidation wave disappeared, and its reduction wave appeared at Ered = −0.59 V (vs Ag/AgCl) upon the addition of 4.0 equv. Fe3+. The sensor displayed high selectivity for Cu2+ and Fe3+ over other ions including Pb2+, Zn2+, Ni2+, Ag+, Cr3+, Mn2+, Al3+, Co2+, Pd2+, Hg2+, Fe2+, Cd2+, Ce3+, Bi3+ and Au3+, the detection limits for Cu2+ and Fe3+ ion reached as low as 5.33 × 10−7 mol/L and 5.34 × 10−7 mol/L, respectively. Furthermore, when Fe3+ existed, Cu2+ can be detected sequentially by the sensor through the absorption spectrum and the color change observed by naked-eyes.
