Tailoring photonic crystals with nanometer-scale precision using polyelectrolyte multilayers.

In this paper, we describe a rapid, accurate, and convenient method for postsynthetically tuning the optical properties of colloidal photonic crystals. High quality photonic crystal films are first synthesized and then coated iteratively with layers of water-soluble polyelectrolytes. The coating process results in nanometer-scale shifts in the photonic stop band, a process which has been monitored by theoretical modeling. The results suggest a fundamentally different, reproducible layering mechanism inside the confined spaces of the colloidal crystal where polyelectrolyte multilayers are less densely packed.

Direct visualization of layer-by-layer self-assembled multilayers of organometallic polymers.

Direct visualization of organometallic-organic and novel all-organometallic multilayer superlattices prepared by layer-by-layer assembly of cationic/anionic polyferrocenylsilane and anionic polystyrene sulfonate polyelectrolytes using a gold coating/transmission electron microscopy (TEM) technique is reported.