Scientists led by Northwestern University have developed an innovative amidinium-based coating that exponentially increases the lifespan and efficiency of perovskite solar cells, offering a promising low-cost alternative to traditional silicon solar panels.
In a landmark achievement that could revolutionize the photovoltaic industry, scientists led by Northwestern University have introduced a novel protective coating for perovskite solar cells. This advancement could substantially extend the operational life of these cells, making them viable for widespread practical applications.
For years, perovskite solar cells have intrigued researchers because of their superior efficiency and lower production costs compared to traditional silicon solar cells. However, their lack of long-term stability under environmental stress has been a significant hurdle. Existing perovskite cells typically employ an ammonium-based coating to enhance efficiency, but these layers degrade under conditions such as heat and moisture.
“State-of-the-art perovskite solar cells typically have ammonium ligands as a passivation layer,” first author Yi Yang, a postdoctoral fellow at Northwestern, said in a news release. “But ammonium tends to break down under thermal stress.”
The researchers resolved this limitation by developing an amidinium-based coating that is significantly more durable. In laboratory experiments, this new protective layer showed a resilience to decomposition that was 10 times greater than conventional ammonium-based coatings. Moreover, the amidinium-coated cells exhibited a T90 lifetime three times longer than their predecessors, indicating the time it takes for a cell’s efficiency to drop by 90% under harsh conditions.
“The field has been working on the stability of perovskite solar cells for a long time,” co-lead author Bin Chen, a research associate professor of chemistry at Northwestern, said in the news release. “So far, most reports focus on improving the stability of the perovskite material itself, overlooking the protective layers. By improving the protective layer, we were able to enhance the solar cells’ overall performance.”
“This work addresses one of the critical barriers to widespread adoption of perovskite solar cells — stability under real-world conditions,” added co-lead author Mercouri Kanatzidis, a professor of chemistry at Northwestern. “By chemically reinforcing the protective layers, we’ve significantly advanced the durability of these cells without compromising their exceptional efficiency, bringing us closer to a practical, low-cost alternative to silicon-based photovoltaics.”
The innovation resulted in a solar cell efficiency of 26.3%, meaning it could convert 26.3% of absorbed sunlight into electricity. The amidinium-coated cells retained 90% of their original efficiency after enduring 1,100 hours of testing in strenuous conditions.
The results are a significant stride forward in the quest for high-efficiency, low-cost solar energy solutions. The research, published in Science, aligns with the Generate pillar of the Paula M. Trienens Institute for Sustainability and Energy at Northwestern. This pillar is dedicated to creating new solar energy production methods focusing on high-efficiency multi-junction solar cells and next-generation materials.
“Perovskite-based solar cells have the potential to contribute to the decarbonization of the electricity supply once we finalize their design, achieve the union of performance and durability, and scale the devices,” added co-lead author Ted Sargent, the Lynn Hopton Davis and Greg Davis Professor Chemistry at Weinberg and professor of electrical and computer engineering at the McCormick School of Engineering, who directs the Trienens Institute. “The primary barrier to the commercialization of perovskite solar cells is their long-term stability. But due to its multi-decade head start, silicon still has an advantage in some areas, including stability. We are working to close that gap.”
This breakthrough research marks a decisive step toward overcoming the primary obstacle hampering the widespread utility of perovskite solar cells — their stability.
With this advancement, the future of solar energy looks both brighter and more sustainable.