Anti-reflection silica coating simultaneously achieving superhydrophobicity and robustness

Anti-reflection film (AR), as a type of optical coating, is applied to surfaces such as lenses, optical elements, and displays to minimize glare and allow more light to enter the eyes. In this study, we propose a novel method to prepare an anti-reflection superhydrophobic silica coating. The original film is made from a fluorine-containing solution and is subsequently modified through gas-phase chemical vapor deposition in a hexamethyldisilazane environment. This modification process reduces the consumption of fluorosilane and improves the transmittance of the coating. The prepared AR film in our work exhibits excellent optical performance with a maximum transmittance of 98.2% across a broad wavelength range of 300–900 nm. Compared to the average transmittance of bare glass at 89.1%, the maximum average transmittance can reach 95.2%. By controlling the amount of ammonia, the refractive index can be adjusted to a low level in the range of 1.08–1.16. Moreover, the superhydrophobic film was treated with wet ammonia to further bolster its mechanical properties. Since the excellent superhydrophobic properties of the prepared AR film, it can repel the dirt adhering to the edge of the film, thus obtaining excellent self-cleaning ability. In addition, the film can recover superhydrophobicity after cleaning with pure alcohol. This work contributes to further promoting the widespread application of AR film. Graphical Abstract