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arXiv · 1203.0663

Phase separation in binary colloids with charge asymmetry

Koki Yoshizawa·Nao Wakabayashi·Masakatsu Yonese·Junpei Yamanaka·C. Patrick Royall
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Abstract

We report that binary dispersions of like-charged colloidal particles with large charge asymmetry but similar size exhibit phase separation into crystal and fluid phases under very low salt conditions. This is unexpected because the effective colloid-colloid pair interactions are accurately described by a Yukawa model which is stable to demixing. We show that colloid-ion interactions provide an energetic driving force for phase separation, which is initiated by crystallization of one species.

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Koki Yoshizawa, Nao Wakabayashi, Masakatsu Yonese, Junpei Yamanaka, C. Patrick Royall. 2012-03-03. Phase separation in binary colloids with charge asymmetry. https://doi.org/10.1039/c2sm26164b

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