Fig. 2

Characterization of fast self-assembled photonic crystals (PCs). (a) Optical images of PCs obtained using silica nanoparticles with diameters of 320 nm, 300 nm, 260 nm, 250 nm and 240 nm, respectively. The bottom bar corresponds to the visible light spectrum with indicated wavelengths. (b) Normalized reflection spectra of PCs obtained with silica nanoparticles of diameters of 320 nm, 300 nm, 290 nm, 260 nm, 250 nm and 240 nm, respectively. (c) Representative SEM images of PCs in the front view (i) and in the side view (ii)