Why are aerogels blue?

The porous structure of aerogel can reflect and scatter the light in it. Gel is a porous material, and the porous structure of aerogel can reflect and scatter light in it, thus producing blue color. The porous structure of aerogels can disperse light into different wavelengths, which makes the scattering of blue light more obvious than other colors, so aerogels appear blue. The pore size of aerogels can be controlled between several nanometers and several microns, and they have great specific surface area and adsorption capacity. Aerogels are widely used, including thermal insulation materials, adsorbents, catalysts, sensors, biomedical materials and other fields.