Stocco, Antonio Mokhtari, Tahereh Haseloff, Günter Erbe, Andreas Sigel, Reinhard 2011-01-13 A light-scattering goniometer for evanescent-wave dynamic light scattering (EWDLS) measurements at a liquid-fluid interface is introduced, and used for measurements on two charge-stabilized polystyrene colloid systems adsorbed to alkane-water interfaces. The goniometer allows an independent variation of the penetration depth and the scattering vector components parallel and perpendicular to a liquid-fluid interface. The possible illumination geometries are compared. Ellipsometry at the liquid-fluid interface is implemented as a complementary tool. In EWDLS measurements, the absence of diffusive motion perpendicular to the interface is demonstrated, which confirms the adsorption of the particles. The two-step decay of the autocorrelation function is interpreted in terms of diffusion within a two-dimensional interface lattice of colloidal particles, stabilized by repulsive electrostatic interactions, and a desorption process. A significant slowing down of the in-plane diffusion of the colloids as compared to the bulk diffusion is observed. application/pdf https://folia.unifr.ch/global/documents/301807 https://folia.unifr.ch/documents/301807/files/sie_ewd.pdf eng info:eu-repo/semantics/altIdentifier/doi/10.1103/PhysRevE.83.011601 info:eu-repo/semantics/openAccess License undefined Physical Review E. - 2011, vol. 83, no. 1, p. 011601 info:eu-repo/classification/udc/53 Evanescent-wave dynamic light scattering at an oil-water interface: Diffusion of interface-adsorbed colloids http://purl.org/coar/resource_type/c_6501