B R Venugopal | PubMed Health

PubMed2006

Layered double hydroxide-CdSe quantum dot composites through colloidal processing: effect of host matrix-nanoparticle interaction on optical behavior.

Layered double hydroxide (LDH)-monodispersed 4-nm CdSe nanoparticle composites were prepared through restacking of layers of colloidally dispersed delaminated LDH in the presence of CdSe nanoparticles in 1-butanol. The composites exhibit a blue shift for CdSe absorption, which increases with a decrease in nanoparticle content. The observed blue shift is due to the interaction of the quantum dots with the LDH layers, which leads to surface modification of the nanoparticles.

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PubMed2005

Effect of various factors influencing the delamination behavior of surfactant intercalated layered double hydroxides.

The delamination-restacking behavior of a number of layered double hydroxides (LDHs) differing in [M(II)]/[M(III)] ratio, constituent metal ions and intercalated surfactant anions in different organic solvents has been studied. Colloidal dispersion due to delamination and the stability of the colloid obtained have been found to be not affected much by the nature of the constituent metal ions but increase with increase in the size of the surfactant anion. LDHs with low [M(II)]/[M(III)] ratio delaminate better than the ones with high [M(II)]/[M(III)] ratio. Delamination is best in alcohols such as 1-butanol, 1-hexanol, 1-octanol and 1-decanol, while a little delamination occurs in nonpolar solvents such as hexane. In all the cases, the original layered solid could be obtained through restacking of layers from the colloidal dispersion.

Journal Article↗