Revisiting aqueous alkaline silicates as precursors for sol‐gel optical coatings

Abstract

Alkaline silicates are well-known soluble silica derivatives already widely used for industrial purposes. Nevertheless, their applications for the elaboration of functional optical coatings have largely been discarded by the sol-gel community who mainly focused on alkoxide precursors. The objective of this work is to reconsider the alkaline silicates sol-gel chemistry, targeting optical coatings of a few hundreds of nanometers. The structures of Li + , Na + , and K + silicate coatings are discussed on the basis of spectroscopic characterizations. We show that a simple washing process allows a postdeposition removal of most alkaline ions, thus preventing the efflorescence effect and improving the aqueous stability of the films. Finally, several examples are shown for the application of alkaline silicates in the elaboration of functional optical coatings following conventional sol-gel chemistry.

Facile preparation of a water-based antireflective SiO2 film with high transmittance for perovskite solar cells

“…17 To cope with this issue, a common practice involves rinsing the AR film with water to remove sodium ions from the surface of the film. 18,19 On the other hand, previous work 20,21 has reported that residual sodium ions at the film–glass interface may enhance interfacial reactions through diffusion after annealing and promoting adhesion, which is beneficial for SiO 2 AR film functioning.…”