Preparation of high color fastness structural colored cotton fabric via SiO2@PDA photonic crystal

Structural color is an important way to achieve the ecological coloring of textiles. SiO 2 microspheres with sizes in the range of 200–337 nm were synthesized by the Stober method and then covered with highly light-absorbing melanin PDA to form SiO 2 @PDA photonic crystals. The SiO 2 @PDA photonic crystals were assembled onto the surface of white cotton fabrics by gravity deposition to achieve structural color. The addition of polyvinylpyrrolidone (PVP) enhances interfacial bonding by forming multiple hydrogen bonds between its lactam group and the phenolic hydroxyl group of PDA, resulting in a structured color cotton fabric with high color fastness. Scanning electron microscopy (SEM) was used to study the structure and morphology of SiO 2 @PDA microspheres. The chemical compositions of PDA and PVP were surveyed by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The surface structural color of cotton fabrics was investigated by UV–Vis reflectance spectroscopy.