Synthesis of CuS Nanoparticles in Water-in-Carbon Dioxide Microemulsions

Abstract

The formation of CuS nanoparticles from Cu(NO 3 ) 2 and Na 2 S by the mixing of two separate water-in-carbon dioxide (W/C) microemulsions supported by the sodium salt of bis (2,2,3,3,4,4,5,5octafluoro-1-pentyl)-2-sulfosuccinate (di-HCF4) was investigated. At a water-to-surfactant ratio of 10 and a copper concentration of 7.8 mM in the aqueous phase, the size of copper sulfide particles ranged from 4 to 6 nm. The temperature-pressure phase diagrams of W/C microemulsions at various electrolyte concentrations in the aqueous phase were also determined. The presence of the electrolytes was found not to affect the cloud-point pressures significantly, even at high concentrations.

Some wet routes for synthesis of hematite nanostructures

“…Some surfactants that have been used in microemulsion synthesis include cetyl trimethylammonium bromide (CTAB), sodium bis-(2-ethylhexyl) sulfosuccinate (AOT), perfluoropolyethercarboxylic (PFPE) acid, sodium lauryl sulfate (SLS), triton X, Igepal, span tween 80 and polyethylene glycol (López-Quintela et al, 2004). The water/oil droplets are dispersed as nano-sized droplets (5-25 nm) surrounded by a monolayer of surfactants in the continuous phase (reverse micelles) and allows for exchange of reactants between these phases leading to reaction within the droplets which acts as nanoreactors (Dong et al, 2002) within which nanomaterials with narrow size range can be prepared (Gupta and Gupta, 2005).…”

Nanoparticles Preparation Using Microemulsion Systems

“…Dong et al prepared CuS nanoparticles by mixing two separate water in carbon dioxide microemulsions stabilized using sodium salt of bis(2,2,3,3,4,4,5,5-octafluoro-1-pentyl)-2-sulfosuccinate (AOT). The size of copper sulfide nanoparticles ranged from 4 to 6 nm (Dong et al, 2002). Wu et al obtained TiO 2 nanoparticles from its precursor titanium (IV) isopropoxide (TTIP) by a combination of supercritical fluid microemulsion and supercritical-drying techniques, in which TTIP hydrolized in reverse micelles (H 2 O being surrounded by CO 2 ) formed by surfactant Zonyl FSJ using a medium of supercritical carbon dioxide.…”

Fluorinated microemulsions as reaction media for fluorous nanoparticles

“…21 The related F-AOT surfactants have been employed to stabilize other systems, in which H-AOT is inactive, such as water-in-scCO 2 (w/scCO 2 ) microemulsions 25 and CuS nanoparticles in pure scCO 2 . 26 Hence such F-surfactants appear to be ideal candidates for stabilizing F-MEs and fluorous NP dispersions.…”