Electrostatically Templated Self-Assembly of Polymeric Particles: The Role of Friction and Shape Complementarity

Abstract

Conductive electrodes held at kV potentials and patterned with non-conductive circular islands can drive templated self-assembly (TSA) of millimeter-sized polymeric particles. It is found, however, that the complementarity of the shapes of the capturing islands and the projected shapes of the adsorbing particles is insufficient to produce high quality assemblies. For instance, while spherical particles center onto circular islands and form highly regular arrays, disk-shaped particles remain off-centered on the same islands. These effects are due to frictional effects that compete with electrostatic forces during TSA. A finite-element model is used to quantify the forces acting in the system and suggests heuristic rules that guide the design of islands capturing particles of desired shapes and sizes.