Structure transitions of polymer-mediated colloidal crystals

The self-assembled colloidal crystals with structure transitions were realized experimentally on substrates with polymer brushes. Such polymer-mediated colloidal crystals were found to experience a series of in-layer structure transitions including stable columnar, polycrystalline, mixed square-hexagonal, square, hexagonal structures when the mass ratio of colloidal particles to free polymers was adjusted from 0.125 to 10. Among these structures, a large area interfacial square structure was proved to be a body-centered tetragonal (BCT) structure in three dimensions in the polymer-mediated colloidal crystals.