Enhanced environmental stability and luminescence performance of CsPbI3 nanocrystals through SDS passivation and LEuH anchoring

Abstract

CsPbI3 perovskite nanocrystals (NCs) have been identified as promising candidates for optoelectronic devices due to their low bandgap, wide absorption spectrum, and high color purity. However, their practical applications are limited by their vulnerability to transforming into the yellow non-perovskite phase in ambient conditions. In this study, we propose a novel approach to prepare highly stable black-phase CsPbI3 NCs by passivating them with sodium dodecyl sulfate (SDS) and anchoring them with flower-like layered europium hydroxide (LEuH). The addition of SDS to CsPbI3 NCs plays a crucial role in inhibiting defect formation by preventing the ligand from desorbing. Furthermore, LEuH, with its surface OH– groups, effectively anchors the CsPbI3 NCs onto its nanosheets, preventing their agglomeration. The resulting composite LEuH-SDS-CsPbI3 nanocomposites exhibit extraordinary environmental stability, maintaining their phase structure even after 60 days of storage under ambient conditions. Additionally, their photoluminescence quantum yield reaches an impressive 95 %. The exceptional luminescence performance of the LEuH-SDS-CsPbI3 nanocomposites opens up new possibilities for their application in optoelectronic devices. Furthermore, when used in white LEDs, these nanocomposites exhibit excellent luminescence efficiencies, further highlighting their potential for commercial utilization in the field.