Ultrafast Rejuvenation of Aged CsPbI 3 Quantum Dots and Efficiency Improvement by Sequential 1-Dodecanethiol Post-Treatment Strategy

Metal halide perovskite CsPbI quantum dots (QDs) have sparked widespread research due to their intriguing optoelectronic. However, the CsPbI QDs undergo inevitable aging and luminescence quenching caused by the weak binding ability of oleate (OA )/oleylammonium (OAm ), hindering further practical application. Herein, we have realized ultrafast rejuvenation of the aged CsPbI QDs that have lost their photoluminescence performance based on a 1-dodecanethiol (DDT) surface ligand to restore the outstanding red light emission with a high photoluminescence quantum yield (PLQY) from 25 to 90%. Furthermore, CsPbI QDs with DDT surface treatment maintain a cubic phase and high PLQY value even after 35 days. The DDT ligands can form a strong bond with Pb and passivate I ion vacancies, enhancing radiative recombination efficiency and thereby improving the PLQY of the QDs. The stable yet easily accessible surface of the DDT-capped CsPbI QDs was successfully employed as white LEDs and exhibited considerable enhanced luminous performance, suggesting promising application in solid-state lighting fields.