Abstract: Antireflective nanoparticle coatings and methods of forming the coatings on substrates are disclosed. One method for forming an antireflective coating includes depositing a nanoparticle coating layer on a substrate, wherein the nanoparticle coating layer includes a colloidal solution of nanoparticles and a solidifying material. The solidifying material includes a silica precursor. The method further includes curing the solidifying material to form silica inter-particle connections between adjacent nanoparticles and between at least some of the nanoparticles and the substrate to bind the nanoparticles to each other and to the substrate to form the antireflective coating.