Toward a full understanding of the growth dynamics, optical response, and crystalline structure of self-assembled photonic colloidal crystal films

Abstract

Recent advances in the comprehension of the growth dynamics of colloidal crystal films opens the door to conscious design of experiments aiming at fabricating lattices in which the density of intrinsic defects is minimized. Since such imperfections have a dramatic effect on scattered light of wavelength smaller than the lattice constant, the evaluation of the experimental optical response at those energy ranges, based on the comparison to rigorous calculations, is identified as the most sensitive guide to accurately evaluate the progress towards the actual realization of defect free colloidal crystals. The importance of the existence of a certain distortion becomes particularly relevant at the above mentioned energy range. We have thoroughly analyzed the effect of fine structural features on the optical response to conclude that, rather than the generally assumed FCC lattice of spheres, opal films are better approximated by a rhombohedral assembly of distorted colloids. Interparticle distance of actual colloidal crystals coincides with the expected diameter for spheres belonging to the same close-packed (111) plane but differs significantly in directions oblique to the [111] one.

Self-Reporting Colorimetric Analysis of Drug Release by Molecular Imprinted Structural Color Contact Lens

“…32,33 The thickness of the colloidal crystal template and size of the central pupil area can be adjusted by tuning the concentration of monodispersed SiO 2 suspension and the evaporation temperature. 34,35 Here, an optimized concentration of 25 g/L and temperature between 80 and 90 °C were used for preparing the colloidal crystal template in molds. 23 The top and cross section of color ring are shown in Figure 2c,d, which clearly exhibited the inverse opal architecture in submicrometer scale and the inverse opal architecture caused the brilliant structural color in lens.…”