Spectroscopic identification of tri-n-octylphosphine oxide (TOPO) impurities and elucidation of their roles in cadmium selenide quantum-wire growth

Fudong Wang, Rui Tang, Jeff L.F. Kao, Sean D. Dingman, William E. Buhro

Research output: Contribution to journalArticlepeer-review

127 Scopus citations

Abstract

Tri-n-octylphosphine oxide (TOPO) is the most commonly used solvent for the synthesis of colloidal nanocrystals. Here we show that the use of different batches of commercially obtained TOPO solvent introduces significant variability into the outcomes of CdSe quantum-wire syntheses. This irreproducibility is attributed to varying amounts of phosphorus-containing impurities in the different TOPO batches. We employ 31P NMR to identify 10 of the common TOPO impurities. Their beneficial, harmful, or negligible effects on quantum-wire growth are determined. The impurity di-n-octylphosphinic acid (DOPA) is found to be the important beneficial TOPO impurity for the reproducible growth of high-quality CdSe quantum wires. DOPA is shown to beneficially modify precursor reactivity through ligand substitution. The other significant TOPO impurities are ranked according to their abilities to similarly influence precursor reactivity. The results are likely of general relevance to most nanocrystal syntheses conducted in TOPO.

Original languageEnglish
Pages (from-to)4983-4994
Number of pages12
JournalJournal of the American Chemical Society
Volume131
Issue number13
DOIs
StatePublished - Apr 8 2009

Fingerprint

Dive into the research topics of 'Spectroscopic identification of tri-n-octylphosphine oxide (TOPO) impurities and elucidation of their roles in cadmium selenide quantum-wire growth'. Together they form a unique fingerprint.

Cite this