TY - JOUR
T1 - Nanofluids
T2 - A new class of materials produced from nanoparticle assemblies
AU - Jagannathan, Ramesh
AU - Irvin, Glen C.
PY - 2005/9
Y1 - 2005/9
N2 - We present evidence of a novel nanostructured fluid, a nanofluid, composed of molecular clusters of a polar organic dye and surfactant. These are not nanoparticles dispersed in a solvent; there are no solvent molecules present. These materials, which are solids under ambient conditions, are non-reactively precipitated from a compressed CO2 solution, resulting in a liquid-like material, which we call a nanofluid. The precipitated dye-surfactant clusters are 1-4 nm in size. This nanofluid exhibits intense luminescent signatures, which are significantly blue-shifted with respect to the dye powder or a solution of it. The X-ray diffraction pattern did not show any structure in the low-angle regime. The fluorinated surfactant is highly soluble in compressed CO2. The polar dye does not dissolve in compressed CO 2 but is solubilized by electrostatic interactions with the surfactant head groups. We believe that the ultrafast and controlled precipitation from compressed CO2 preserves the electrostatic coupling and promotes a structured molecular cluster. Additionally, we demonstrate the formation of organic nanoparticles using this controlled precipitation process from compressed CO2.
AB - We present evidence of a novel nanostructured fluid, a nanofluid, composed of molecular clusters of a polar organic dye and surfactant. These are not nanoparticles dispersed in a solvent; there are no solvent molecules present. These materials, which are solids under ambient conditions, are non-reactively precipitated from a compressed CO2 solution, resulting in a liquid-like material, which we call a nanofluid. The precipitated dye-surfactant clusters are 1-4 nm in size. This nanofluid exhibits intense luminescent signatures, which are significantly blue-shifted with respect to the dye powder or a solution of it. The X-ray diffraction pattern did not show any structure in the low-angle regime. The fluorinated surfactant is highly soluble in compressed CO2. The polar dye does not dissolve in compressed CO 2 but is solubilized by electrostatic interactions with the surfactant head groups. We believe that the ultrafast and controlled precipitation from compressed CO2 preserves the electrostatic coupling and promotes a structured molecular cluster. Additionally, we demonstrate the formation of organic nanoparticles using this controlled precipitation process from compressed CO2.
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U2 - 10.1002/adfm.200400474
DO - 10.1002/adfm.200400474
M3 - Article
AN - SCOPUS:24644487010
VL - 15
SP - 1501
EP - 1510
JO - Advanced Materials for Optics and Electronics
JF - Advanced Materials for Optics and Electronics
SN - 1057-9257
IS - 9
ER -