Mechanically Durable Superhydrophilic Antireflective Nanoparticles Coatings via Layer-by-Layer Assembly Followed by Post-treatments

Silica nanoparticles coatings assembled via layer-by-layer (LbL) assembly have attracted much attention because of their superhydrophilic and antireflective properties. However, the mechanical durability of such coatings is usually not sufficient for practical applications. The current work was carried out to improve the mechanical durability of the coatings by post treatments. Coatings were fabricated from silica nanoparticles, polyelectrolytes of poly(diallyldimethylammonium) chloride (PDDA) and sodium poly(4-styrenesulfonate) (PSS) via LbL assembly. Glass substrates covered with (PDDA/SiO(2))(6) coatings exhibited the highest transmittance. (PDDA/SiO(2))(6) coatings were sequentially subjected to hydrothermal treatment (124 degrees C for 1 h) and dynamic hardening (200 s), respectively. The as-treated coating exhibited both superhydrophilic and antireflective properties. A maximum transmittance of 99.0% was achieved in the visible range for the (PDDA/SiO(2))(6) coating. Meanwhile the mechanical durability of these coatings has been greatly enhanced by the post treatments.