Harnessing Pb –S Interactions for Long‐Term Water Stability in Cesium Lead Halide Perovskite Nanocrystals

By employing a ligand exchange strategy with (11-mercaptoundecyl)-N,N,N-trimethylammonium bromide (MUTAB), the authors capitalized on lead-sulfur (Pb −S) interactions. MUTAB passivates the nanocrystal (NC) surface, ensuring water dispersibility and stability, unlike oleyl amine/oleic acid (OAm/OAc)-capped counterparts prone to rapid degradation. The optoelectronic properties of MUTAB-stabilized NCs are validated through efficient 3,3′,5,5′- tetramethylbenzidine (TMB) oxidation under visible light irradiation. AbstractLead halide perovskite nanocrystals (LHP NCs) have garnered attention as promising light-harvesting materials for optoelectronics and photovoltaic devices, attributed to their impressive optoelectronic properties. However, their susceptibility to moisture-induced degradation has hindered their practical applications. Despite various encapsulation strategies, challenges persist in maintaining their stability and optoelectronic performance simultaneously. Here, a ligand exchange approach is proposed using (11-mercaptoundecyl)-N,N,N-trimethylammonium bromide (MUTAB) to enhance the stability and dispersibility of CsPbBr3 (CPB) NCs in aqueous environments. MUTAB enables effective surface passivation of the CPB NCs via robust Pb –S interactions at the S-terminal while concurrently directing water molecules through the unbound cationic N-terminal or vice versa, ensuring water dispersibility and stability. Spectroscopic analysis confirms retained structural and o...
Source: Small - Category: Nanotechnology Authors: Tags: Research Article Source Type: research