Synthesis of SiO2@Ag for light absorption and the fabrication of highly color-saturated amorphous photonic crystals

The artificial design of nano-submicron structures to fabricate amorphous photonic crystals (APCs) is an effective means of obtaining non-iridescent structural color. APCs show great potential for applications in various fields, such as coating, textile coloring, displays, anti-counterfeiting, etc. However, a sharp fall in the structural color saturation can result due to incoherent scattering. In this paper, a type of light-absorbing material, SiO2@Ag, is prepared via a redox method. Non-iridescent structural color films with excellent color visibility and color saturation can be constructed through the layer-by-layer self-assembly of SiO2@Ag and SiO2 microspheres. Due to the inherent property of absorbing incoherent scattering light by the Ag nanoparticles, better structural color is generated without changing the originally ordered structure of the APC itself. Furthermore, no redshift or blueshift is caused by SiO2@Ag, which helps to maintain the color consistency well. Thus, excellent structure stability and color visibility are shown for the new type of APC film fabricated here, which will provide innovative ideas for the design and fabrication of non-iridescent structural color materials.