Multi-phased cesium lead iodide quantum dots with large stokes shift

Abstract

Lead halide perovskite quantum dots (QDs) have emerged as one of the most promising candidates for lighting and biomedical applications. However, further applications are limited by energy transfer of Förster resonance energy transfer (FRET) or photon reabsorption between different QDs due to QDs with small Stokes shifts. Here, we first report intrinsic cesium lead iodide QDs with large Stokes shifts from 262 to 289 nm with PL peaks in the range of 630 to 658 nm. We show that the large Stokes shift is attributed to the morphology of QDs with multiple phases. Our results in intrinsic lead iodide perovskite QDs with large Stokes shift may open new avenues in resolving energy transfer in biomedical and lighting applications.