Controllable preparation of SiO2-VO2 films with desired structural color and thermochromic properties based on 3DPC templates

In order to achieve compatible stealth via VO2 in visible and near-infrared bands, the SiO2-VO2 films with desired structural colors and thermochromic properties were successfully prepared based on three-dimensional photonic crystal (3DPC) structure of SiO2 templates. It is found that with the varying diameters of SiO2 spheres, the SiO2-VO2 films appear beautiful red, green, and blue color, respectively. The SiO2-VO2 films keep the same structural color with SiO2 3DPC templates and the good thermochromic properties of VO2. In addition, the reflectivity of the SiO2-VO2 films increased obviously and possessed thermochromic properties in near infrared region when the temperature ranged from 30 °C to 80 °C. The calculation and preparation methods used in this work may provide both theoretical and practical supports for the feasible preparation of SiO2-VO2 films with required colors and thermochromic properties.