High-performance meso–macroporous SiO2 antireflective coatings with enhanced optical and mechanical stability for solar energy applications†

Antireflective (AR) coatings are indispensable for optimizing light energy capture in transparent materials and mitigating glare-induced hazards. However, current nanoporous coatings suffer from small pore sizes (2–10 nm) that are prone to blockage by atmospheric moisture and organic pollutants, limiting their practical performance. Herein, we report a scalable, low-cost fabrication method for robust meso–macroporous (∼46 nm) SiO₂ coatings with transmittance as high as 99.3% on glass, featuring superhydrophilicity for effective antifogging. By utilizing a sol–gel phase separation approach, polyacrylic acid acts as a dynamic template in an ethanol–water cosolvent system to enable precise size control. The resulting coatings exhibit remarkable adhesion (grade 5B), exceptional scratch resistance (over 100 cycles), and stable performance under humid heat treatment for 15 days. When applied to transparent conductive glass and solar cells, these coatings improve light transmittance by over 8.7% and solar cell relative efficiency by ∼7.7%. Moreover, a simple dip-coating technique exhibits exceptional scalability for fabricating relatively large-area (75 cm²) AR coatings. This approach offers a versatile platform for designing durable, high-performance porous AR coatings, with transformative potential in solar energy, optical devices, and architectural applications.