Improved Durability Hydrophobic Self-Cleaning Coating Based on OTES-Modified SiO₂/PVDF for Photovoltaic Module...

Area of Science:

• Materials Science
• Surface Chemistry
• Renewable Energy Technologies

Background:

• Hydrophobic self-cleaning coatings are valuable for PV glass and precision instruments.
• Fluorine-containing modifiers limit practical use due to poor durability and environmental concerns.

Purpose of the Study:

• To develop an eco-friendly, mechanically durable hydrophobic self-cleaning coating.
• To address limitations of traditional fluorine-based coatings.

Main Methods:

• Developed a composite coating using non-fluorinated nano-SiO2 modified with OTES and combined with PVDF.
• Applied the coating to glass via simple spraying.
• Optimized the OTES-SiO2 to PVDF volume ratio for best performance.

Main Results:

• The OTES-SiO2/PVDF coating achieved a water contact angle of 115.9° and pencil hardness of 6H.
• Visible light transmittance was 75%, with a slight initial reduction in photovoltaic conversion efficiency.
• The coating demonstrated effective self-cleaning and dust resistance, with efficiency recovery after cleaning.

Conclusions:

• The developed fluorine-free coating offers a low-cost, scalable solution with enhanced mechanical durability and self-cleaning properties.
• The coating is suitable for arid, dusty environments like northwest China, reducing PV module maintenance.
• The study elucidates the performance enhancement mechanism involving "covalent grafting-interface entanglement-micronano structure".