CdS Nanoplates Modification as a Platform for Synthesis of Blue-Emitting Nanoparticles

• Main Authors: Anna Lesiak, Mateusz Banski, Hanna Woznica, Andrzej Żak, Joanna Cabaj, Artur Podhorodecki
• Format: Article
• Language: English
• Published: MDPI AG 2021-06-01
• Series: International Journal of Molecular Sciences
• Subjects: 3-mercaptopropionic acid; blue emitting quantum dots; <span style="font-variant: small-caps">d</span>-penicillamine; ligand exchange; CdS nanoplatelets; phase transfer
• Online Access: https://www.mdpi.com/1422-0067/22/12/6477
• ISSN: 1661-6596; 1422-0067

In this paper, the study of surface modification of two-dimensional (2D), non-luminescent CdS nanoplates (NPLs) by thiol-containing ligands is presented. We show that a process of twophase transfers with appropriate ligand exchange transforms non-luminescent NPLs into spherical CdS nanoparticles (NPs) exhibiting a blue photoluminescence with exceptionally high quantum yield ~90%. In the process, transfer from inorganic solvent to water is performed, with appropriately selected ligand molecules and pH values (forward phase transfer), which produces NPs with modified size and shape. Then, in reverse phase transfer, NPs are transferred back to toluene due to surface modification by combined Cd (OL)₂ and Cd (Ac)₂. As a result, spherical NPs are formed (average diameter between 4 and 6 nm) with PL QY as high as 90%. This is unique for core only CdS NPs without inorganic shell.