Fluorescence Light-Up Electrospun Membrane Incorporated with PbBr2 as a Highly Selective Fluorescence Probe for the Detection of Cs+

This study introduces a novel fluorescent light-up electrospun membrane, integrating PbBr 2 , which serves as an exceptionally selective probe for the detection of cesium ions (Cs + ). Leveraging the superior optical properties of CsPbBr 3 perovskite nanocrystals (PNCs), the researchers employ electrospinning technology to fabricate a test strip, namely PbBr 2 @polyacrylonitrile (PbBr 2 @PAN) nanofiber membranes, capable of swiftly detecting Cs + in water merely by observing changes in the nanocrystals' luminescence with the naked eye. By the introduction of NH 4 + -modified montmorillonite (NH 4 + -MMT), PbBr 2 -MT@PAN nanofiber membranes is obtained. The selectivity and sensitivity to Cs + can be further improved because NH 4 + -MMT endows PbBr 2 -MT@PAN nanofiber membranes with the hydrophilic property and selective adsorption toward Cs + ions. The membrane's fabrication is simple, scalable, and cost-effective, with high cesium selectivity and sensitivity down to 44 ppb. This innovation enables efficient, on-site cesium monitoring critical for environmental safety and nuclear waste management.