Electrostatically tuned interactions in silica microsphere-polystyrene nanoparticle mixtures.

Angel T Chan; Jennifer A Lewis

doi:10.1021/la0510073

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Electrostatically tuned interactions in silica microsphere-polystyrene nanoparticle mixtures.

Angel T Chan·Jennifer A Lewis

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Abstract

We explore the generality of nanoparticle haloing as a novel colloidal stabilization mechanism in binary mixtures of silica microspheres and polystyrene nanoparticles. By selectively tuning their electrostatic interactions, both the initial microsphere stability and the role of nanoparticle additions are varied. Adsorption isotherm and zeta potential measurements indicate that highly charged nanoparticles exhibit a weak (haloing) association with negligibly charged microspheres, whereas they either strongly adsorb onto oppositely charged or are repelled by like-charged microsphere surfaces, respectively. Bulk sedimentation and confocal scanning fluorescence microscopy reveal that important differences in system stability emerge depending on whether the added nanoparticles serve as haloing, bridging, or depletant species.

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Microspheres Nanoparticles Particle Size Polystyrenes Silicon Dioxide Static Electricity Surface Properties Journal Article Research Support, Non-U.S. Gov't

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Angel T Chan, Jennifer A Lewis. 2005-09-13. Electrostatically tuned interactions in silica microsphere-polystyrene nanoparticle mixtures.. https://doi.org/10.1021/la0510073

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