A highly water-stable dual-emission fluorescent probe based on Eu3+-loaded MOF for the simultaneous detection and quantification of Fe3+ and Al3+ in swine wastewater

A novel dual-emissive Eu3+-loaded metal–organic framework (MOF) is designed and successfully fabricated by introducing 2-hydroxyterephthalic acid (H2BDC-OH) and Eu3+ ions into an UiO-66-type MOF material. The obtained MOF, here referred to as EuUCH, exhibits dual emission at 450 and 614 nm, and both emissions are quite stable in aqueous media in the pH range of 4–11. EuUCH is characterized by a high selectivity and sensitivity toward Fe3+ and Al3+, which yield different responsive modes. The two emissions of EuUCH are quenched by Fe3+; by contrast, only the emission at 450 nm is quenched by Al3+ showing a ratiometric fluorescence signal. More importantly, as there is no clear interference between the signals of Fe3+ and Al3+, EuUCH is successfully utilized for the simultaneous detection of Fe3+ and Al3+ in their mixtures. In addition, the simultaneous quantification of Fe3+ and Al3+ is achieved in more complicated swine wastewater with good recoveries. This work provides a water-stable dual-emissive probe and the possibility to achieve the simultaneous quantification of Fe3+ and Al3+ in complicated environment wastewater. [Display omitted] •A highly water-stable dual-emission Eu3+-loaded MOF (EuUCH) has been successfully fabricated.•EuUCH specifically recognizes Fe3+ and Al3+ with two different response signals.•The simultaneous quantification of Fe3+ and Al3+ in their mixture is achieved.•The probe could be practically applied for simultaneous quantification of Fe3+ and Al3+ in environmental wastewater.