Red-Emissive Nanocrystals of Cs4MnxCd1-xSb2Cl12 Layered Perovskite

Layered double perovskite are currently investigated as emerging halide-based materials for optoelectronic applications. Herein, we present the synthesis of Cs4MnxCd1-xSb2Cl12 (0 ≤ x ≤ 1) nanocrystals (NCs). X-ray powder diffraction evidences the retaining of the same crystal structure for all the inspected composition; transmission electron microscopy revealed monodisperse particles with a mean size of 10.6 nm. The absorption spectra seem to be mostly determined by transitions related to Sb3+, whereas Mn2+ induced a red emission in the 625 – 650 nm range. The emission intensity and position varies with the Mn2+ content and reaches the maximum for the composition with x = 0.12. Finally, we demonstrated that the photoluminescence quantum yield (PLQY) of the latter NCs was boosted from 0.3% to 3.9% through a post-synthesis treatment. The present work enlarges the knowledge of colloidal layered double perovskite nanocrystals, stimulating future investigations of this emerging class of material.