Heteroaggregation between Charged and Neutral Particles
| Autor: | Tianchi Cao, Gregor Trefalt, Takuya Sugimoto, Michal Borkovec |
|---|---|
| Rok vydání: | 2020 |
| Předmět: |
Chemistry
02 engineering and technology Surfaces and Interfaces 010402 general chemistry 021001 nanoscience & nanotechnology Condensed Matter Physics 01 natural sciences Polystyrene latex 0104 chemical sciences Chemical engineering Colloidal particle ddc:540 Electrochemistry General Materials Science 0210 nano-technology Spectroscopy |
| Zdroj: | Langmuir, Vol. 36, No 19 (2020) pp. 5303-5311 |
| ISSN: | 1520-5827 0743-7463 |
| Popis: | Experimentally determined heteroaggregation rates between charged and neutral colloidal particles are reported for the first time. Different positively and negatively charged polystyrene latex particles are investigated. The neutral particles are obtained through adsorption of an appropriate amount of oppositely charged additives, such as aliphatic oligoamines, iron cyanide complexes, or alkyl sulfates. Heteroaggregation rates were measured with time-resolved multi-angle light scattering. One observes that heteroaggregation between charged and neutral particles is always fast and diffusion controlled. These experimental values are compared with calculations of the Derjaguin, Landau, Verwey, and Overbeek (DLVO) theory, whereby one finds that this heteroaggregation process is highly sensitive to charge regulation conditions. The comparison with experiments shows unambiguously that the surface of the neutral particles regulates strongly, and probably behaves close to a constant potential surface. This observation is in line with direct force measurements on similar systems, and further agrees with the fact that for neutral surfaces the capacitance of the diffuse layer is expected to be much smaller than the one of the inner layer. |
| Databáze: | OpenAIRE |
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