Abstract: This study developed a multifunctional aluminum oxide (Al2O3) film combining anti-reflective and superhydrophobic properties for enhanced photovoltaic (PV) performance in outdoor applications. The film was created on glass substrates using a sol–gel, dip coating, and controlled etching process, resulting in a porous surface with grass-like nanostructures. After 512 s of etching, the film achieved a roughness of 23.63 nm and a refractive index of 1.14 at 550 nm. It demonstrated excellent broadband anti-reflection, with 96.86% average transmittance and 3.07% reflectance across the 350–1500 nm spectrum, peaking at 99.30% transmittance at 480 nm. The film maintained over 90% transmittance at angles up to 45°, providing omnidirectional functionality crucial for solar panels. Its superhydrophobicity (162.3°water contact angle and hysteresis 7.5°) ensures self-cleaning. When applied as a solar cell cover glass coating, the film enhanced short-circuit current density and power conversion efficiency. A 19.19% efficiency increase was observed at a 60°incidence angle, demonstrating the film’s potential for significant PV performance improvement.
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Author(s): Ramon Dadalto Carvalho, Cristian Dias Fernandes, Marcelo Barbalho Pereira, Samantha Cardoso Alves, Pedro Lovato Gomes Jardim, Sérgio da Silva Cava, Mateus Meneghetti Ferrer, Cristiane Wienke Raubach, Elson Longo, Mario Lucio Moreira
First published: 25/04/2025
