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arXiv · 1511.02493

Hiding in plain view: Colloidal self-assembly from polydisperse populations

Bernard Cabane·Joaquim Li·Franck Artzner·Robert Botet·Christophe Labbez·Guillaume Bareigts·Michael Sztucki·Lucas Goehring
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Abstract

We report small-angle x-ray scattering (SAXS) experiments on aqueous dispersions of colloidal silica with a broad monomodal size distribution (polydispersity 18%, size 8 nm). Over a range of volume fractions the silica particles segregate to build first one, then two distinct sets of colloidal crystals. These dispersions thus demonstrate fractional crystallization and multiple-phase (bcc, Laves AB$_2$, liquid) coexistence. Their remarkable ability to build complex crystal structures from a polydisperse population originates from the intermediate-range nature of interparticle forces, and suggests routes for designing self-assembling colloidal crystals from the bottom-up.

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Bernard Cabane, Joaquim Li, Franck Artzner, Robert Botet, Christophe Labbez, Guillaume Bareigts, Michael Sztucki, Lucas Goehring. 2015-11-08. Hiding in plain view: Colloidal self-assembly from polydisperse populations. https://doi.org/10.1103/physrevlett.116.208001

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