Synthesis and self-assembly of photonic materials from nanocrystalline titania sheets.

We describe the use of benzyl alcohols in a solvothermal/alcoholysis reaction to form nanocrystalline sheets of anatase titania. By tuning the reaction conditions, we adjust the size of the nanosheets. The type and density of benzyl groups that decorate the basal plane of the titania sheets control the self-assembly into layered structures. These layered materials can be grown from solid substrates to create iridescent thin films that reflect specific wavelengths of visible light.