Fabrication of hollow colloidal crystal cylinders and their inverted polymeric replicas

We fabricated colloidal crystals on a fiber by a dip-coating method. The self-assembly of monodisperse colloidal particles was affected by the curvature of the fiber (the reciprocal of the fiber radius). As the fiber became smaller in diameter, fewer layers of the colloidal spheres were coated for a given lift-up speed. The hollow colloidal crystal cylinders were used as a template for creating macroporous structure having three-dimensionally interconnected air cavities. Specifically, the polymer precursor was infiltrated into the colloidal crystal template and the macroporous polymer structures were obtained after the selective etching of colloidal particles.