A simple biphasic route to water soluble dithiocarbamate functionalized quantum dots

TitleA simple biphasic route to water soluble dithiocarbamate functionalized quantum dots
Publication TypeJournal Article
Year of Publication2008
AuthorsWang J, Xu J, Goodman MD, Chen Y, Cai M, Shinar J, Lin ZQ
Journal TitleJournal of Materials Chemistry
Volume18
Pages3270-3274
Type of ArticleArticle
ISBN Number0959-9428
Accession NumberISI:000257426000014
KeywordsCDSE NANOCRYSTALS, films, IN-VIVO, MULTIPLE EXCITON GENERATION, NANOCRYSTALS SURFACE FUNCTIONALIZATION, nanoparticles, nanowires, PHOTOLUMINESCENCE, SENSITIZED SOLAR-CELLS, TIO2 NANOTUBE ARRAYS
Abstract

Hydrophobic trioctylphosphine oxide-functionalized CdS equantum dots (CdSe-TOPO QDs) were transferred from organic solvent to aqueous solution via a simple yet novel biphasic ligand exchange process in one step, which involved the in-situ formation of hydrophilic dithiocarbamate moieties and subsequent ligand exchange with TOPO at the chloroform/water interface. The resulting water dispersible, dithiocarbamate functionalized CdSe QDs (i.e., D-CdSe) exhibited an increased photoluminescence (PL) quantum yield as compared to the original CdSe-TOPO QDs, suggesting an effective passivation of dithiocarbamate ligands on the QD surface. The D-CdSe QDs were then mixed with hydroxyl terminated TiO2 nanoparticles. A decrease in the PL of the mixture was observed, indicating a possible charge transfer from the D-CdSe QDs to the TiO2 nanoparticles. The reaction of the carboxyl group on the D-CdSe surface with the hydroxyl group on the TiO2 rendered QDs in direct contact with TiO2, thereby facilitating the electronic interaction between them.

DOI10.1039/b803618g
Alternate JournalJ. Mater. Chem.