COLL 165 |
| Nanosized polyoxometalate macroions are fully hydrophilic and self assemble into large single-layer, hollow spherical, vesicle-like “blackberry”-type structures. Understanding the driving forces behind this unique self-assembly is important in studying these new structures. We have concluded that van der Waals forces, chemical interactions, and hydrophobic interactions are not the dominant forces, and speculate that the counter-ion-mediated attraction might be important. In this study we show that by replacing the counterions, in this case H +, but different monovalent cations, obvious changes in blackberry size are observed. This is a strong indication that counter-cations play an important role in the strong attraction among macroanions, even for mono-valent cations. The blackberry formation also accelerates with additional cations. This strong attraction to cations is also observed with organic dyes using scanning confocal microscopy and phase transfer with ionic surfactants. |
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Fundamental Research in Colloid and Surface Chemistry
6:00 PM-8:00 PM, Monday, August 20, 2007 BCEC -- East Registration, Poster
Division of Colloid & Surface Chemistry |