Layer-by-layer templated growth of colloidal crystals with packing and pattern control

Abstract

Layer-by-layer deposition of polymer colloidal particles on patterned electrode surfaces under an applied electric field is discussed. Colloidal crystals with a low packing density, grown on hexagonally patterned electrode substrates from single-sized colloidal particles, are presented. A nucleation mechanism of colloidal layer formation determined the grain size of the colloidal crystals. Alternating deposition of large (L) and small (S) colloidal particles with radii ratios of R S/ R L = 0.41 and 0.49 on patterned surfaces with hexagonal and square types of pattern led to the formation of 2D and 3D binary colloidal crystals with LS, LS 2 and LS 3 stoichiometries. Planar defects in form of colloidal monolayers composed of colloidal particles of smaller sizes were easily introduced into colloidal crystals using the layer-by-layer deposition technique. This method allows one to fabricate stable non-close-packed colloidal crystal structures in a direct deposition process.