A nanoplatform Of Eu3+ @ citric acid-functionalized UiO-66: Facile preparation and highly-sensitive detection For Fe3+ and Cr2O72- ions in an aqueous system

A novel fluorescent sensor material of Eu 3+ @ Citric acid-functionalized UiO-66 (denoted as Eu 3+ @UiO-66-CA) was prepared successfully via a two-step post synthetic modification towards UiO-66. The as-obtained Eu 3+ @UiO-66-CA presented the characteristic emission of Eu 3+ ions (λ ex = 270 nm), which could be used for rapidly detecting Fe 3+ and Cr 2 O 7 2- ions by luminescence quenching in aqueous solution. The detection process for Fe 3+ ion (detection limit, 18.1  μ M) and Cr 2 O 7 2- ion (detection limit, 8.5  μ M) exhibited the high selectivity and excellent anti-interference ability. Systematic investigations were employed to make clear the mechanism of fluorescence quenching after adding Fe 3+ and Cr 2 O 7 2- ions. Moreover, the Eu 3+ @UiO-66-CA was also used for the determination of Fe 3+ and Cr 2 O 7 2- ions in the Yellow River and tap water.