Floating nematic phase in colloidal platelet-sphere mixtures

• DOI: 10.1038/srep00789
• Publication Date: 2012-11-19T10:44:14Z
• Authors: Daniel de las Heras; Nisha Doshi; Terence Cosgrove; Jonathan Phipps; David I. Gittins; Jeroen S. van Dui...; Matthias Schmidt
• Keywords: Binodal; Sedimentation; Gibbsite; Péclet number; Settling

The phase behaviour of colloidal dispersions is interesting for fundamental reasons and technological applications such as photonic crystals electronic paper. Sedimentation, which in everyday life relevant from blood analysis to the shelf paint, a means determine boundaries by observing distinct layers samples that are sedimentation-diffusion equilibrium. However, disentangling effects due interparticle interactions, generate bulk diagram, those gravity complex task. Here we show line space chemical potentials µi, where i labels species, represents sedimented sample each crossing this sedimentation path with binodal generates an interface under gravity. Complex stacks can result, sandwich floating nematic layer between top bottom isotropic phases observed mixture silica spheres gibbsite platelets.