Solvothermal synthesis of KBi3F10:Eu3+ phosphors as selective three-in-one fluorescent probes for Cr3+, CrO42− and Cr2O72− ion detection.

Chromium is a common heavy metal element that is harmful to the ecosystem as well as human health, so sensitive detection of chromium ions in solution is important for life and health. In this paper, a series of Eu3+-doped KBi3F10 fluorescent powders were successfully synthesized by a one-step solvothermal method for the selective detection of Cr3+, CrO42− and Cr2O72− ions in an aqueous solution. When adjusting the pH value to 3 and adding PVP as an additive, the obtained KBi3F10:12%Eu3+ phosphor showed excellent red luminescence. Due to the competitive absorption and the inner filter effect of Cr3+, CrO42− and Cr2O72− ions, the red emission from Eu3+ ions produces fluorescence quenching, which can be used to detect them with good selectivity. And the detection limits are as low as 0.19 μM, 0.38 μM and 0.094 μM for Cr3+, CrO42− and Cr2O72− ions, respectively. Other metal ions and common anions showed little interference with chromium ion detection. The obtained fluorescent probe has good recyclability, accurate and reliable detection results, simple operation and low cost and is easy to promote, which make it an excellent three-in-one probe for chromium detection. [ABSTRACT FROM AUTHOR]