Nanocellulose infused with purple onion extract shields photo voltaic cells from UV degradation
by Robert Schreiber
Berlin, Germany (SPX) Mar 20, 2025
Researchers on the College of Turku in Finland have developed a bio-based movie that gives high-performance UV safety for photo voltaic cells, using nanocellulose handled with purple onion pores and skin extract. This marks the primary comparative research of how varied bio-derived UV filters carry out over time.
Photo voltaic cells, inclined to wreck from ultraviolet radiation, are sometimes shielded by petroleum-derived movies akin to polyvinyl fluoride (PVF) or polyethylene terephthalate (PET). In an effort to cut back reliance on fossil fuels, researchers are exploring sustainable alternate options like nanocellulose, a cloth made by refining cellulose into nanoscale fibers that may be custom-made for UV blocking capabilities.
The research, carried out in collaboration with Aalto College in Finland and Wageningen College within the Netherlands, revealed that nanocellulose movies dyed with purple onion extract blocked 99.9% of UV rays as much as 400 nanometres. This efficiency surpassed that of business PET-based filters, which served as a benchmark within the analysis.
“Nanocellulose movies handled with purple onion dye are a promising possibility in functions the place the protecting materials must be bio-based,” said Doctoral Researcher Rustem Nizamov from the College of Turku.
Researchers evaluated 4 sorts of nanocellulose movies enhanced with purple onion extract, lignin, or iron ions, all recognized for his or her UV-filtering properties. Amongst them, the movie incorporating purple onion extract demonstrated the best UV shielding.
Efficient UV safety should be balanced with the power to transmit seen and near-infrared gentle, important for photo voltaic vitality conversion. Whereas supplies like lignin excel in UV absorption, their darkish hue hinders transparency. In distinction, the purple onion-based movie achieved over 80% gentle transmission at wavelengths between 650 and 1,100 nanometres, sustaining this stage over prolonged testing.
To simulate extended out of doors use, the movies had been uncovered to synthetic gentle for 1,000 hours, equating to roughly one yr of pure daylight in central Europe. Researchers tracked modifications within the movies and photo voltaic cells by way of digital imaging.
“The research emphasised the significance of long-term testing for UV filters, because the UV safety and lightweight transmittance of the opposite bio-based filters modified considerably over time. For instance, the movies handled with iron ions had good preliminary transmittance which decreased after growing old,” tells Nizamov.
Checks centered on dye-sensitised photo voltaic cells, that are notably liable to UV-induced deterioration. The findings even have broader implications for different photo voltaic applied sciences like perovskite and natural photovoltaics, the place bio-based UV filters may play an important function.
“These outcomes are additionally related for the UV safety of different sorts of photo voltaic cells, together with perovskite and natural photovoltaics, in addition to any software the place using a bio-based UV filter is paramount,” Nizamov says.
Wanting forward, the researchers purpose to create biodegradable photo voltaic cells that would function energy sources in functions akin to meals packaging sensors.
“The forest business is inquisitive about creating new high-grade merchandise. Within the subject of electronics, these may additionally be elements for photo voltaic cells,” famous Kati Miettunen, Professor in Supplies Engineering.
The College of Turku’s Photo voltaic Vitality Supplies and Techniques (SEMS) group is exploring methods to combine photo voltaic applied sciences into broader vitality methods.
This work was a part of the BioEST undertaking, supported by the Analysis Council of Finland.
Associated Hyperlinks
College of Turku
All About Photo voltaic Vitality at SolarDaily.com