TiO2 and TiO2–Ag powders and thin layer toward self-cleaning coatings for PV panel integrated with sound-absorbing screens: Technical approaches

This work aims at assessment of TiO2 as the main layer component for self-cleaning layers in photovoltaic panels. TiO2 (derived from titanium (IV) butoxide or titanium (IV) isopropoxide) without and with silver was examined to find titania suitable microstructure and optical properties. For this purpose silver amounts ranging from 0.1 to 1% were used for 3 separate chemical methods of modification. Microstructure of powders was characterized by means of scanning electron microscopy (SEM) and transmission electron microscopy (TEM) with X-ray energy dispersion spectroscopy. Three techniques: spin-coating, doctor blade, and spray-coating were used to deposit TiO2 and TiO2–Ag layers on glass and silicon solar cells. The photocatalytic activity of TiO2 and TiO2–Ag were investigated in the presence of methylene blue. Concentration of dye, amount of silver, type of TiO2 with Ag modification and stability over time were analysed towards the best photocatalytic properties. Finally, TiO2 layers which were used to coat a new type of photovoltaic modules had marginal influence on photovoltaic parameters. •One-step chemical modified TiO2–Ag powders resulted in an irregular powder grain structure with different geometry.•Two-step chemical modification yielded in refined powder morphology.•Layers formed by spin-coating and doctor blade techniques showed hydrophilic behaviour.•TiO2 and TiO2–Ag layers exhibited photocatalytic activity.•TiO2 without and with silver modification demonstrated suitable for self-cleaning layers.