Preparation of high transmission superhydrophobic <scp> SiO ₂ </scp> thin films and simulation of solar cell efficiency

Abstract This study presents a cost‐effective sol–gel approach to fabricate nanoporous SiO₂ thin films with simultaneous high transmittance and superhydrophobicity for solar cell efficiency enhancement. By incorporating trimethylethoxysilane (TMES) as a hydrophobic modifier in an alkaline‐catalyzed hybrid sol, the optimized SiO₂ film achieved a peak transmittance of 97.05% (5.56% higher than bare glass) and a water contact angle of 150°, demonstrating exceptional anti‐reflective and self‐cleaning properties. The nano‐porous structure, characterized by a critical particle gap ( D c ) of 40 ± 10 nm, was systematically analyzed through scanning electron microscopy (SEM) and theoretical models, revealing that surface roughness‐induced air entrapment significantly contributed to hydrophobicity. Spectral response simulations indicated a proportional relationship between transmittance improvement and short‐circuit current increment (Δ J sc ), validating the film's potential to enhance solar cell efficiency. Durability tests confirmed minimal performance degradation (0.31% transmittance loss and 15° contact angle reduction after 5000 water droplet impacts), highlighting robust environmental adaptability. This work not only provides a scalable method for multifunctional anti‐reflective coatings but also bridges material design with photovoltaic applications, offering insights into sustainable energy technology development.