Silica antireflective films on glass produced by the sol-gel method

Up to now antireflective silica thin films deposited on glass do not have enough strength and display poor adhesion to the substrate. Three methods to obtain silica antireflective films on glass were surveyed to identify the best way to produce the antireflective effect on glass by introducing a certain degree of porosity. Porous silica layers, obtained from the polymeric and colloidal methods, permit a considerable reduction of these light reflections compared with uncoated glasses in all the cases studied, but the degree of reduction as well as the adhesive properties is different depending on the method used to achieve the precursor solution. The AM1.5 solar transmittance increased from 0.915 for the bare slide up to 0.970 for the best-made sample corresponding to the Triton-doped silica.