The coating is created by depositing a layer of thin, highly porous silica-based film onto the surface of a glass plate. This reduces the amount of light reflected from the surface of the glass – thereby ensuring the highest possible transmission of light and maximizing the solar power output. The chemistry and structure of the coating are designed to withstand weather conditions ranging from harsh UV light to acid rain and extreme temperature fluctuations – help extending the life of the solar panel to a potential 25 years.
Nanopores: The key to reflectivity
The key to the anti-reflective coating’s reflective properties lies in millions of nanopores that create a refractive index between the air and glass. To enable this porous structure, we created a formulation consisting of “core-shell” particles, made from a latex polymer core and a silica-based shell. In turn, a wide range of deposition methods (like roll-coating and slot-die coating) can then be used to deposit a 100-150-nanometer-thick layer onto the surface of the glass. The spaces between the core-shell particles are filled with a modified silica binder, which acts as a glue. From here it is cured, with the polymer core removed by thermal degradation to leave a silica-glass layer with a high internal porosity that can significantly reduce reflection. The end result? A solar module energy gain of up to 4%.