Anti-reflection coatings with enhanced abrasion and scratch resistance properties

The development of multifunctional coatings plays a crucial role in the achievement of more competitive glasses for optical and solar application, among others. In this respect, coatings that provide high transmittance together with abrasion resistance could mean an added value to such glasses. Herein, we report design and preparation of novel multifunctional coatings that present anti-reflection (AR), scratch and abrasion resistance properties. This is achieved by a coating structure with a composite top layer comprising at least one type of metal oxide (ZrO2 or TiO2) or silane compound with low-refractive-index SiO2 layer. The above composite layer is applied onto a high refractive metal oxide layer, either titania or zirconia. The properties of the coatings were studied by different characterization techniques such as UV-visible-NIR spectrophotometer, FESEM, FIB, SEM-EDAX, haze and transmission meter, ellipsometer, pencil hardness tester, Taber Abrader and water contact angle measurement. The results indicate that the AR films produced by a bilayer system especially using a low refractive nanocomposite layer as a top layer and a high refractive layer as a bottom layer showed a high transmission in the visible range with comparatively better abrasion and scratch resistances. Moreover, the coatings developed on silicon wafer used as an absorber substrate for PV application exhibited an excellent low reflectance property, < 2.5 % average reflection from 300 to 1500 nm which makes it applicable in both optical and photovoltaic systems with high mechanical stability. Composite bilayer anti-reflection coatings with enhanced abrasion and scratch resistance properties.