TY - JOUR
T1 - Preparation of Fluorous Solvent-Dispersed Fe3O4 Nanocrystals
T2 - Role of Oxygen in Ligand Exchange
AU - Kim, Youngsun
AU - Lee, Sangyoup
AU - Kim, Sehoon
N1 - Funding Information:
This work is supported by grants from the Korea Institute of Energy Technology Evaluation and Planning (No. 20142020103790) and the Intramural Research Program of KIST.
Publisher Copyright:
© 2016 American Chemical Society.
Copyright:
Copyright 2016 Elsevier B.V., All rights reserved.
PY - 2016/4/12
Y1 - 2016/4/12
N2 - Perfluorinated ligand-passivated Fe3O4 nanocrystals were prepared through a biphasic ligand exchange method. It was found that dissolved oxygen in the reaction media predominantly determined the degree of ligand exchange and the resultant dispersion property of nanocrystals in a fluorous solvent. X-ray photoelectron spectroscopic analyses revealed that dissolved oxygen molecules bind to the surface iron species of nanocrystals in competition with the carboxylate moiety of ligands during the exchange reaction, lowering the degree of ligand exchange and colloidal stability significantly. Reducing the oxygen content of the fluorous phase by N2 bubbling was found to result in a highly stable dispersion of phase-transferred Fe3O4 nanocrystals with a single-particle size distribution maintained for a few months.
AB - Perfluorinated ligand-passivated Fe3O4 nanocrystals were prepared through a biphasic ligand exchange method. It was found that dissolved oxygen in the reaction media predominantly determined the degree of ligand exchange and the resultant dispersion property of nanocrystals in a fluorous solvent. X-ray photoelectron spectroscopic analyses revealed that dissolved oxygen molecules bind to the surface iron species of nanocrystals in competition with the carboxylate moiety of ligands during the exchange reaction, lowering the degree of ligand exchange and colloidal stability significantly. Reducing the oxygen content of the fluorous phase by N2 bubbling was found to result in a highly stable dispersion of phase-transferred Fe3O4 nanocrystals with a single-particle size distribution maintained for a few months.
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U2 - 10.1021/acs.langmuir.6b00526
DO - 10.1021/acs.langmuir.6b00526
M3 - Article
AN - SCOPUS:84964470874
VL - 32
SP - 3348
EP - 3353
JO - Langmuir
JF - Langmuir
SN - 0743-7463
IS - 14
ER -