LAUSR

Abstract A probe that can efficiently detect harmful Cr(III) and Cr(VI) at the same time is urgently needed. In aqueous solution, Cr(III) and Cr(VI) are in the form of the cation (Cr3+) and anions (CrO42−, HCrO4−, or Cr2O72−), respectively. Owning to their opposite charge, it is a great challenge to develop a two-in-one probe for Cr detection. Here, we report an amino-functionalized YF3:Eu3+ fluorescent probe that can successfully detect both Cr3+ and Cr2O72− with good selectivity. The surface amino groups can enhance the adsorption affinity of both Cr3+ and Cr2O72− ions by forming coordination bonds and electrostatic attraction, respectively. As a result, the detection limits of Cr3+ and Cr2O72− ions are determined to be as low as 1.88 μM and 1.34 μM, respectively. Finally, the amino-functionalized YF3:Eu3+ is also successfully applied to detect Cr3+ and Cr2O72− in practical rain water and tap water samples.