Multipole expansion of the electrostatic interaction between charged colloids at interfaces

The interaction of charged nanoparticles at interfaces

We study charged nanoparticles adsorbed onto surfactant bilayers using small-angle scattering of synchrotron radiation. The in-plane interaction of the particles is well described by a DLVO component (measured independently in solution) and a repulsive dipolar interaction due to the presence of the interface, with an amplitude close to the theoretical prediction. We prove that charged nanoparti...

Virial expansion for charged colloids and electrolytes

Using a field-theoretic approach, we derive the first few coefficients of the exact low-density (“virial”) expansion of a binary mixture of positively and negatively charged hard spheres (two-component hard-core plasma, TCPHC). Our calculations are nonperturbative with respect to the diameters d+ and d− and charge valences q+ and q− of positive and negative ions. Consequently, our closed-form e...

Colloids at interfaces: Pinned down.

In 1903 Walter Ramsden found that an air bubble placed in a liquid suspension of microscopic particles “can be seen to pick up the particles ... and to retain them obstinately ...”1 Ramsden had discovered the strong affinity of colloidal particles to fluid interfaces, an affinity that a century later can be harnessed to make microstructured materials such as Pickering emulsions, colloidosomes a...

Colloids at Liquid-liquid Interfaces

Electrostatic interaction of oppositely charged double layers

We determined with anisotropic hypernetted chain theory the effective pressure and counterion excess of two oppositely charged surfaces immersed in an electrolyte solution. These thermodynamic properties are enhanced in surfaces with evenly smeared surface charges with respect to those containing confined mobile charges. For low surface charges and moderate reservoir salt concentration ions are...