Researchers at the University of California, Los Angeles have found a way to prevent perovskite materials from degrading when exposed to direct sunlight. They found that the regression was caused by a special surface treatment, ironically designed just to correct defects and increase efficiency.
The fact is that the surface treatment layer of organic ions creates a trap for charged electrons, thereby destabilizing the configuration of perovskite atoms, which leads to its degeneration. UCLA scientists combined the positive and negative ions that make up the processing material, thereby leveling the charge imbalance.
The researchers tested the photovoltaic cells treated with the new compound under powerful, 24-hour lighting to speed up their aging. Perovskite retained 87% of its effectiveness after being exposed to over 2,000 hours of exposure to the toxic environment, a much better result than the untreated elements, whose efficiency dropped to 65%.
“Our perovskite solar panels are among the most stable today. We have also laid down new fundamental knowledge from which the community can continue to develop and improve our versatile technique to develop even more stable perovskite solar cells,” said Sean Tan, co-author of the study.
Metal halide perovskites are comparable in efficiency to silicon, but much cheaper, lighter and more flexible.