Compact nanopillar array with enhanced anti-accumulation of multiphase matter on transparent superhydrophobic glass

Abstract

The rapid depletion of non-renewable fossil fuels has made the utilization of solar energy an essential component in both human society and industry. However, in practical applications, substantial soiling of photovoltaic panel surfaces can negatively affect the photoelectric conversion efficiency due to light absorption and reflection. Previously, oil-repellent or oleophilic coatings were employed to prevent the deposition of contaminants on glass, but these methods demonstrated limited efficacy, particularly under real-world conditions. To enhance resistance to multiphase contaminations, we developed a novel transparent superhydrophobic glass surface with a high density of nanopillars, achieved through a repeated dewetting technique. The compact nanopillar structures provide exceptional wetting and optical properties, including high transparency, low reflectance, superhydrophobicity, and oleophobicity. The densely arranged nanopillars also potentially reduce contamination penetration into interstitial gaps and decrease the contact area with the underlying glass substrate, demonstrating remarkable anti-accumulation capability against multiphase pollutants, such as condensation, frost, ice, dust, and bacteria. Additionally, condensation tests reveal that compact surfaces display a significant dewdrop self-jumping phenomenon, which is absent in conventional nanopillar surfaces. Thus, our findings propose an alternative approach for the future design of transparent superhydrophobic anti-soiling glass.