Physico-chemical investigation of nanostructures in liquid phases: nickel chloride ionic clusters confined in sodium bis(2-ethylhexyl) sulfosuccinate reverse micelles

J Colloid Interface Sci. 2009 Aug 1;336(1):176-82. doi: 10.1016/j.jcis.2009.03.066. Epub 2009 Apr 7.

Abstract

The confinement of finite amounts of nickel chloride in the hydrophilic core of sodium bis(2-ethylhexyl) sulfosuccinate (AOT) reverse micelles dispersed in n-heptane has been investigated by FT-IR, UV-vis-NIR and fluorescence spectroscopies. The analysis of experimental data consistently leads to hypothesize that NiCl(2) forms small size ionic clusters stabilized by a monolayer of oriented surfactant molecules. Due to confinement and interfacial effects, these ionic clusters show peculiar photophysical properties, which are different from those possessed by the bulk material. From NiCl(2)/AOT/n-heptane solutions, by evaporation of the organic solvent, interesting salt/surfactant nanocomposites at various salt concentrations have been prepared and characterised by WAXS. On the other hand, after mix with Na(2)S-containing dry micellar systems, the formation of NiS nanoparticles have been ascertained by UV-vis spectroscopy.