CsPbBr3 perovskite nanoplatelets: Excellent probes for spectrofluorimetric sensing of chloride and arsenite

Herein, we report a novel analytical exploitation of selective but very facile anion exchange induced phase transformations of CsPbBr3 Perovskite crystallites. Specifically, with CsPbBr3 Perovskite as Spectrofluorimetric probes, we demonstrate a simple, quick and economical analytical procedure for sensing and quantification of chloride content in room temperature ionic liquids (RTILs), and that of toxic pollutant Arsenic (III) in water samples. The presented approach relies on the variations in photoluminescence characteristics of CsPbBr3 Perovskite nanoplatelets on account of very facile substitution of their bromide ions by chloride ions available in their vicinity. This unique property of CsPbBr3 Perovskite nanoplatelets ensures detection of chloride impurity in RTIL samples, within the concentration range of 0.007-0.016 ppb with LOD c.a. 0.0010 ppb ± 0.44% and of Arsenic in water samples within the concentration range 0.48-4.32 ppb with LOD as low as c.a. 0.074 ppb ± 0.46%.