Industry 4.0
Vol. 11 (2026), Issue 2, pg(s) 69-71

DOMINANT TECHNOLOGIES IN “INDUSTRY 4.0”

Preparation and Optical Properties of Gelatin-SiO2 Hybrid Coatings on Glasses for Photovoltaic Applications

  • 1 Bulgarian Academy of Sciences, Institute of Metal Science, Equipment, and Technologies “Acad. A. Balevski” with Center for Hydro- and Aerodynamics, 67 "Shipchenski prohod" str., 1574 Sofia, Bulgaria
  • 2 Bulgarian Academy of Sciences, Central Laboratory of Solar Energy and New Energy Sources, Sofia, Bulgaria

Abstract

In this study, gelatin-SiO2 hybrid coatings were prepared on glass substrates using an acid-catalyzed sol-gel method. The deposited layers were subjected to thermal treatment at 50°C, 150°C, and 250°C to evaluate the effect of temperature on their structure and optical properties. Spectroscopic investigations in the UV-VIS-NIR range show that the hybrid coatings enhance optical transmittance and reduce reflective losses compared to uncoated glass. The best optical performance was observed for the sample thermally treated at 150 °C (GS 150), where an optimal balance between the organic (gelatin) and inorganic (SiO2) phases was achieved, resulting in maximum transmittance and minimal light reflection. At lower treatment temperatures (50°C), the coating exhibited higher porosity but lower structural stability, whereas at higher temperatures (250°C), partial thermal degradation of the gelatin phase led to layer densification and a slight reduction in the antireflective effect. These results demonstrate that gelatin can be successfully used as a biopolymer component to control the microstructure and optical properties of sol-gel hybrid coatings. Improving optical transmittance and reducing reflective losses of glass surfaces is crucial for enhancing photovoltaic module efficiency, as it allows a greater amount of solar radiation to reach the active layer of solar cells.

Keywords

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