Optical behaviour of sol–gel derived photonic structures formed by submicron silica spheres*
نویسندگان
چکیده
Sol–gel synthesis of powders consisting of regularly shaped submicron silica spheres (∅400–600 nm) is described. IR and absorption spectra of such powders have been obtained. The IR spectra demonstrate that the silica spheres heated at 800 °C are hydroxyl-free. The TEM measurements show that the dimensions of silica nanoparticles do not change during heating. Films of self-organized silica nanospheres deposited on a glass support exhibit the photonic crystal effect.
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