Large-area porous pseudoboehmite superhydrophobic self-cleaning coatings for solar panels and outdoor field evaluation

Superhydrophobic transparent coatings have emerged as attractive surface modifiers for photovoltaic applications owing to their low cost, facile fabrication, self-cleaning functionality, and effectiveness in mitigating dust accumulation. Despite these advantages, the long-term durability and environmental stability of such coatings under harsh outdoor operating conditions remain critical challenges that must be addressed to enable reliable large-scale deployment. Large-area pseudo-boehmite-based superhydrophobic coatings have been developed and successfully scaled to dimensions of 890 mm × 665 mm using industrially relevant spray and bar-coating techniques. Field evaluations conducted at two independent outdoor sites demonstrated exceptional functional performance and environmental robustness. The coatings exhibited an ultralow roll-off angle (<2°) and a high static water contact angle (>175°), while simultaneously providing antireflective behaviour and maintaining high optical transmittance. Long-term outdoor exposure over a ten-month period revealed that coated photovoltaic modules consistently outperformed uncoated counterparts, primarily due to enhanced self-cleaning efficiency and reduced optical losses. Comprehensive quality assurance testing confirmed compliance with international reliability standards, validating the mechanical durability and environmental stability of the coated modules. Collectively, these results establish the high technology readiness and industrial applicability of the developed large-area self-cleaning coatings for photovoltaic installations.