Characterization of titanium dioxide nanoparticles dispersed in organic ligand solutions by using a diffusion-ordered spectroscopy-based strategy.
Diffusion-ordered NMR spectroscopy (DOSY NMR) is presented as a tool for the determination of the diffusion coefficients of organic ligands in suspensions of titanium dioxide nanoparticles. The nanoparticles were prepared by a sol-gel process by hydrolysis and condensation reactions of titanium tetra-n-butoxide in the presence of pentane-2,4-dione (acacH: acetylacetone), as well as para-toluenesulfonic acid (pTsA) and n-butanol (nBuOH). NMR spectroscopic studies were performed in various deuterated solvents, on both dispersed xerosols and diluted sols. The bipolar-pulsed field gradient longitudinal eddy-current delay (LED) pulse sequence was used for data acquisition. The data were processed by inverse Laplace transformation (ILT), by using a maximum entropy algorithm, to afford 2D DOSY spectra. Different diffusion regimes for organic ligands in the bound and unbound states were successfully discriminated, more particularly in [D3]acetonitrile, thus allowing assessment of their interactions with the nanoparticles.
Van Lokeren
Luk
L
High Resolution NMR Centre, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussel, Belgium.
Maheut
Géraldine
G
Ribot
François
F
Escax
Virginie
V
Verbruggen
Ingrid
I
Sanchez
Clément
C
Martins
José C
JC
Biesemans
Monique
M
Willem
Rudolph
R