Structuring of nanoparticle suspension probed by neutron reflectivity

The behaviour of colloidal particles at water-solid interfaces is relevant in material science, food processing, medicine and environmental engineering. A team from the University of Geneva with researchers from the Budapest Neutron Centre used neutron reflectivity to study colloidal silica nanoparticle suspensions near the (negatively) like-charged native-oxide-covered surface of Si. Intriguingly, the nanospheres develop a self-organised damped, oscillatory concentration profile normal to the interface, as demonstrated in the figure.