Self-assembled surface patterns of binary colloidal crystals

Co-assembly of binary dispersions of monodisperse microspheres with large size ratios has been used to produce well-ordered hexagonally close-packed monolayers of large spheres with a superimposed pattern of small spheres (see Figure). ne architectures obtained are determined by the size and concentration ratios of the microspheres in the dispersions, are very diverse, and can be obtained reproducibly over millimeter length scales.