UNSW Sydney researchers have developed a new method to monitor how solar cells are damaged by ultraviolet (UV) light and how they can naturally recover, offering potential improvements for solar panel manufacturing.
The team, led by Scientia Professor Xiaojing Hao, devised a microscopic monitoring technique that allows engineers to observe chemical changes in high-efficiency silicon solar cells in real time.
In a university release, researchers said this could help manufacturers test and certify panels more accurately and efficiently.
“This new method can be used directly on the production line to quickly check how well solar cells resist UV damage, making it useful for future quality control during manufacturing,” Professor Hao said.
Silicon solar cells gradually lose efficiency due to UV-induced degradation, with some studies showing up to a 10 per cent drop after accelerated testing equivalent to 2,000 hours of sun exposure. While previous research noted that some performance could recover under normal sunlight, the underlying material changes had remained unclear.
The UNSW team, including Dr Ziheng Liu, Dr Pengfei Zhang, and Dr Caixia Li, used ultraviolet Raman spectroscopy to observe molecular changes without damaging the cells.
The technique revealed that UV light temporarily alters chemical bonds involving hydrogen, silicon, and boron near the cell surface. When exposed to normal light, these bonds can repair themselves, restoring the material at an atomic level.
“This confirms that recovery is not just an electrical effect,” Dr Liu said. “The material itself is repairing at the atomic level.”
The monitoring method has implications for solar manufacturing, where traditional UV testing can take days or weeks and may overstate degradation.
By distinguishing between reversible and permanent changes, the method could help manufacturers improve quality control, screen materials, and refine panel designs before full-scale production.
“This work gives us a clearer picture of how solar cells behave in the real world,” Professor Hao added. “With better monitoring tools, we can design better tests, better panels, and ultimately more reliable solar energy systems.”
The research was published in Energy & Environmental Science and supported by the ARC Research Hub for Photovoltaic Solar Panel Recycling and Sustainability.
