Transparent Nanostructured BiVO₄ Double Films with Blue Light Shielding Capabilities to Prevent Damage to ARPE-19 Cells

The hazards posed by blue light to human eyes are attracting significant attention owing to increasing exposure to electronic devices as well as artificial illumination. Therefore, in this study, nanostructured BiVO4 (BVO) double films were developed using an economical and environmentally friendly sol–gel spin-coating method; the films exhibited excellent blue light shielding capabilities. They could block 65.25% of the blue light in the 415–455 nm wavelength range while simultaneously maintaining an average transmittance greater than 85% in the 500–800 nm wavelength range. Moreover, the damp heat test (85 °C, 85% relative humidity) showed the excellent stability of the BVO filters as their transmittances remained unchanged for 15 days. Importantly, cell experiments were performed to further confirm the protective effects of the BVO filters against the hazards posed by blue light to ARPE-19 cells (human retinal pigment epithelium cell line). Furthermore, the blue light weighted radiance LB decreased by 34.32%, and the color rendering index showed negligible differences after applying an upscaled BVO filter to a phone screen. These cost-efficient, ecofriendly, highly reliable, and large-area nanostructured BVO films with high blue light shielding efficiency have potential applications in various areas.