All-clay photonic crystals

Hierarchically structured "all-clay" 1D and 3D inverse photonic crystals were fabricated, featuring the crystalline layered microstructure of the phyllosilicate Laponite combined with crystalline macroporosity on the submicron scale. By using simple hard-templating protocols based on monodisperse polystyrene spheres, periodic layered silicate and inverse opal architectures with photonic crystal properties are accessible, which exhibit reflectivities of the stop band in excess of 50%. The combination of intrinsic chemical functionality with structural color makes such hierarchical "all-clay" architectures potential scaffolds in color-tunable chemo-optical devices.