Highly selective fluorescence turn-on determination of Pb(II) in Water by in-situ enrichment of Pb(II) and MAPbBr3 perovskite growth in sulfydryl functionalized mesoporous alumina film

Highly fluorescent methylammonium lead bromide (MAPbBr 3 ) perovskite could in situ grow in a sulfydryl functionalized mesoporous alumina film when methylammonium bromide (MABr) meets the sulfydryl-captured Pb(II). In this work, the extraction ability of the mesoporous alumina film towards Pb(II) was found to drastically enhanced after sulfydryl modification. Under the optimal conditions, the Pb(II) adsorption capacity of the sulfydryl functionalized film was 94.9 μg/g. With the strong extraction capability to Pb(II), fluorescence turn-on determination of Pb(II) was enabled by in-situ formation of MAPbBr 3 perovskite in the sulfydryl functionalized alumina film, and a limit of detection (LOD) as low as 5 × 10 −3 μg/mL was achieved. This method integrates the extraction and background-free determination of Pb(II), well addressed the low concentration determination issue and facilitating the whole analysis processes.