Preparation And Properties Of Al₂O₃/ZnO One-dimensional Photonic Crystal Colored Metal/Fiber

As an important mean of constructing structural color,photonic crystals display vivid color by selectively reflecting light located in a certain frequency range of the visible region.Compared with traditional organic dyes and pigments,photonic crystal structural color have the advantages of high brightness,high saturation,high stability,non-fading,and environmental friendliness,as well as the effects of polarization and iridescence.Photonic crystals are usually fabricated via self-assembly of monodisperse colloidal microspheres.However,since microspheres are connected by weak interaction forces such as hydrogen bonding,van der waals force and electrostatic force,which reduce the mechanical stability of structural color and greatly limit the practical application of photonic crystal structural color.Therefore,the construction of photonic crystal structural color with excellent mechanical rubustness is still a great challenge.In this paper,a series of photonic crystal colored metals,carbon fibers and polyester fibers with high-saturation,high-stability,adjustable color were prepared by atomic layer deposition,which forms chemical bonds and one-dimensional dense photonic crystal structures through the mutual chemical interaction of precursors on the surface of the substrate.Firstly,Al₂O₃/ZnO with large refractive index difference were deposited on the surface of metallic steel via atomic layer deposition technology as periodic photonic crystal layer,the structural colors of purple,green,yellow,orange and red with bright color,high saturation and strong stability based on photonic crystals were prepared by controlling the number of cycles of deposition.The reflectance spectra shows that the reflection peak position gradually shifts from456 nm to 718 nm as the thickness of the ZnO layer increases.Angle-resolved reflection spectra demonstrates that the colorful metals are angle-dependent.Rubbing fastness,water jet impact,particle erosion and light aging tests indicate that the sample has excellent mechanical robustness.Tape peeling test data indicates that the sample does not have good peel resistance.Secondly,colored carbon fibers and its fabrics with bright color and high stability were also prepared by depositing Al₂O₃/ZnO one-dimensional photonic crystals on the surface of carbon fibers and their fabrics.The results of angle-resolved reflection spectra reveal that the colored carbon fibers have the optical reflection properties of radial angle-independence and axial angle-dependence.The introduction of high-strength and low-elastic inorganic metal oxides improves the tensile strength of carbon fibers,which increases from 3.1 GPa to 5.1 GPa.It was indicated that the samples had excellent stability via rubbing,laundering,and xenon arc fading lamp test.Utilizing the reflection characteristics in visible?380-800 nm?and near-infrared region?800-1100 nm?of the photonic crystal,it is further used as thermal insulation materials,and the temperature can be lowered by 12°C under a standard solar illumination?910 W/m²?.Finally,Al₂O₃/ZnO photonic crystals were deposited on the surface of polyester fibers,and a series of one-dimensional photonic crystal colored polyester fibers with excellent mechanical properties such as rubbing robustness,washing resistance and sun exposure were prepared.It was proved that photonic crystals were successfully deposited on polyester fibers through scanning electron microscopy,spectrum and other characterizations.It was found that the photonic crystal on the surface of the sample enhanced the shape memory property of the fibers,and it could quickly recover to a shape close to the initial state within 10 s at 110°C.At the same time,it is applied to optical waveguide fibers according to the photonic band gap effect of photonic crystals,the photonic band gap type wearable colored fibers have good application prospects in the fields of flexible display and optical transmission.