In situ functionalization of self-assembled dendrimer nanofibers with cadmium sulfide quantum dots through simple ionic-substitution

Astachov, Vladimir and Garzoni, Matteo and Danani, Andrea and Choy, Kwang-Leong and Pavan, Giovanni Maria and Fahmi, Amir (2016) In situ functionalization of self-assembled dendrimer nanofibers with cadmium sulfide quantum dots through simple ionic-substitution. New Journal of Chemistry, 40 (7). ISSN 1144-0546

Full text not available from this repository.

Abstract

Cadmium sulfide quantum dots (CdS-QDs) can be generated along poly(propylene imine) (PPI) dendrimer-based self-assembled nanofibers through ionic substitution. The supramolecular nanofibers are obtained via self-assembly of cationic PPI dendrimers in aqueous solution containing cadmium acetate. The dissociated asymmetric acetate (AcO–) ions are acting as “glue” for the self-assembly process of the nanofibers formation. The semiconductive CdS nanoparticles are synthesized at room temperature along the self-assembled nanofibers by addition of sodium sulphide (Na2S) in solution. Molecular dynamics (MD) simulation shows that the higher affinity of SH– ions (from dissociated Na2S) for Cd2+, compared to that of AcO–, triggers ionic substitution at the interface between the dendrimers. Microscopy measurements namely Atomic Force Micrsocopy (AFM) and Transmission Electron Microscopy confirm the self-assembly of the fibers formation and the alignment of CdS quantum dots along the filaments having final size of ~2 nanometers. The obtained absorbance results show presence of quantum confinement effect. Since these self-assembled fibers can be disassembled by adding electrolyte such as sodium chloride in solution (ionic competition), this work is proposing a new facile route to obtain functional nanostructured hybrid materials in a convenient way for the next generation of miniaturised devices.

Actions (login required)

View Item View Item