Anti-reflective coatings prepared via layer-by-layer assembly of mesoporous silica nanoparticles and polyelectrolytes

Mesoporous silica nanoparticles (NPs) with diameters of ∼30 nm were fabricated using a dialysis process. The resulting NPs exhibit high colloidal stability and are applicable for the preparation of coating films on glass substrates via electrostatic layer-by-layer (LbL) assembly using cationic polyelectrolytes. The thickness and packing density of coating films can be controlled by layer number and mesoporous silica NP dispersion concentration. It was found that glass substrates that were coated with mesoporous silica NPs in an LbL process exhibited high anti-reflective (AR) performance. The highest AR effects (<1% in the wavelength region of 450-600 nm) were obtained with films prepared with six bilayers of cationic polyelectrolytes and mesoporous silica NPs at a concentration of 40 μg ml^-1.