Base-catalyzed synthesis of superhydrophobic and antireflective films for enhanced photoelectronic applications

In this work, a facile, cost-effective and environmentally friendly approach is developed to synthesize transparent silica sol for fabricating antireflective (AR) and superhydrophobic (SH) films on soda–lime glass. The transparent silica sol is prepared at room temperature by modification of hexamethyl disilazane (HMDS) on colloidal silica nanoparticles (NPs) which are synthesized via base-catalyzed hydrolysis of tetraethoxysilane (TEOS) in the presence of ammonia-free alkaline solution (i.e., NaOH). The AR and SH silica films are then achieved by dip-coating. The average transmittance, water static contact angle (CA) and sliding angle (SA) of the resulting film can reach 93.1%, 169.7° and 3.0°, respectively, exhibiting both AR and SH properties. In particular, the excellent SH and AR properties of the resulting film facilitate not only the excellent self-cleaning performance but also the increasing light transmittance and thus an enhanced power conversion efficiency (PCE) in photovoltaic module.