Hydrophobizing of polycarbonate surface and life cycle assessment for clean technologies

Climate change causes extreme weather conditions including heavy rains and storms around the globe. Utilization of renewable energy sources becomes a necessity for minimizing carbon emission. Solar power systems have great potential for renewable and green energy generation. Photovoltaic farms are prone to environmental dust due to attainment of low performance and degradation of active device elements in harsh environments with dusty and humid conditions. Polycarbonate sheets possess potential being utilized as a protective cover over photovoltaic panels preventing undesirable and adverse effects in harsh environments. Surface hydrophobicity incorporating self-cleaning becomes critical for dust removal from protective layer surfaces with lowering energy harvesting performance. In the present study, hydrophobizing of polycarbonate sheet is considered incorporating different processes including laser texturing, solution crystallization, and functionalized nano particles coating. These processes and the resulting surface topology, wetting states, and mechanical and optical properties are examined accommodating analytical tools. Life Cycle Analysis (LCA) is conducted to assess the impact of each hydrophobizing process on the natural ecosystem. We demonstrated that laser texturing and solution crystallization result in surface topology with randomly oriented micro-size pillars while creating hydrophobic surface with 150° contact angle. However, contact angle hysteresis remains high and UV-visible transmittance of surface reduces notably particularly for crystallized surface. Functionalized nano silica particle coated surface has extremely low contact angle hysteresis with excellent UV-visible transmittance. Among hydrophobizing processes considered, functionalized nano silica particles result in lowest environmental impact in all categories incorporated in LCA.