Self-assembly Of Photonic Crystals Based On Monodisperse SiO₂ Nanospheres

As an important industry in China,the textile industry is facing a serious problem of backward dyeing and finishing technology.Dyeing and finishing processes of natural dyes and synthetic dyes not only have poor dyeing fastness,but also cause environmental pollution.In this paper,we prepared photonic crystals on glass and silk substrates by vertical deposition and self-assembly of SiO₂ nanospheres,and finished the coloring of silk fabrics.Compared with the traditional dyeing and finishing technology,the color obtained by the technology is brighter and brighter,and toxic and harmful substances are not produced in the coloring process,so the technology is a new technology with low cost,simple operation and environmental friendliness.The specific research contents are as follows:（1）Firstly,monodisperse SiO₂ microspheres were prepared by St（?）ber method.The effects of ammonia concentration,tetraethyl orthosilicate（TEOS）concentration and reaction temperature on the preparation of SiO₂ microspheres were systematically discussed,and the SiO₂ microspheres with particle size of 76～540 nm were successfully prepared.The prepared SiO₂ microspheres were characterized by XRD,SEM and FT-IR.The particle size,morphology and dispersion characteristics of SiO₂ microspheres prepared under different reaction conditions were discussed.（2）Secondly,SiO₂ photonic crystals were fabricated on glass substrates by vertical deposition self-assembly method.Photonic crystal films with different color effects were prepared by using SiO₂ microspheres with different particle sizes.The photonic crystal surface morphology,microsphere arrangement,and defect status were discussed by metallographic microscope and SEM,and the reason of photonic crystal stripes on the glass was analyzed.（3）Finally,preparing the photonic crystal structure color on the silk by utilizing a vertical deposition self-assembly method.The photonic crystal structural colors with different color rendering effects were constructed on silk substrate by using SiO₂microspheres with different particle sizes.The relationship between the particle size and the color rendering effect of the structural colors was analyzed,and the iridescence effect of the photonic crystal structure on silk was observed from different angles.In this paper,the photonic crystal structural colors with high saturation,high brightness and iridescence effect were successfully prepared on silk by vertical deposition self-assembly method,and different structural colors were obtained by controlling the size of SiO₂ nanospheres.