Multifunctional NIR-reflective and self-cleaning UV-cured coating for solar cell applications based on cycloaliphatic epoxy resin

• We prepared epoxy coating with IR-reflecting and hydrophobic properties.
• The films act as good “filters” in the NIR region.
• These coatings are able to give better performances when applied on solar cells.
• The coating containing the silicone additive showed a water drop sliding.

We report here a simple, cheap and scale up process for obtaining a multifunctional coating with both, IR reflective and hydrophobic properties. These coatings can be applied on solar devices in order to limit their overheating under operating conditions. The system is based on UV-curable epoxy coating containing IR-reflective fillers and a silicone additive to modify the surface properties with a good hydrophobicity enhancement. The filler dispersion into the epoxy UV-curable resin did not significantly influence the photocuring rate, while a slight decrease of the final epoxy group conversion was evidenced. The optical properties of the obtained coatings have been evaluated by UV–vis–NIR spectroscopy showing that the films act as good “filters” in the NIR region, giving rise to a reduction of the absorbed heat and of the working temperature of the cells. A pronounced increase of hydrophobicity for the films containing the silicone additive was observed. The optical properties were not affected by the addition of the silicone additive.

Multi-functional coating with both IR-reflecting and hydrophobic properties were prepared based on a UV-curable epoxy coating containing IR-reflective fillers and a silicone additive. The crosslinked films act as good “filters” in the NIR region, giving rise to a reduction of the absorbed heat and of the working temperature of a tested solar cell.Figure optionsDownload as PowerPoint slide