Perovskite solar cells, 66% longer lifespan
Perovskite Solar Cells, Latest Scientific Advances
The lifespan of perovskite solar cells has been improved by 66%. This significant achievement comes from new international research that addresses the weak points of next-generation photovoltaics without compromising performance. Published in Energy and Environmental Science and led by the University of Surrey and Imperial College London, this research achieves a remarkable feat: creating high-efficiency perovskite solar cells that are also highly stable under environmental conditions.
Why is this an achievement?
Humidity and heat are two environmental factors that limit the performance and stability of this class of synthetic materials, particularly those based on lead and tin. These technical challenges have hindered the widespread deployment of perovskite photovoltaics.
To reduce this “sensitivity,” it is essential to fully understand the processes and reactions occurring inside the cell. This is exactly how the scientists uncovered an unknown degradation pathway related to the hole transport material (positive charge carriers).
Identifying Hidden Mechanisms that Contribute to Efficiency and Stability Losses
The team focused on understanding the efficiency and stability losses caused by the hole transport layer made from PEDOT:PSS. PEDOT:PSS is one of the most studied materials for this purpose due to its high mobility and conductivity, as well as its low cost. To achieve high energy efficiency, thiocyanate additives are usually added to this material. However, this compromises the stability of the device because the interaction between thiocyanate and iodine accelerates the formation of cyanogen, which is worsened in the presence of humidity.
The group identified this step and introduced an iodine-reducing agent to inhibit the chemical reactions causing degradation. This approach not only increased the efficiency of lead-tin perovskite solar cells to 23.2% – one of the highest figures in this segment – but also extended their lifespan by 66%.
As Hashini Perera, researcher and lead author of the study at the Advanced Technology Institute at the University of Surrey, explains: “The knowledge we developed through this work has allowed us to identify a strategy that improves efficiency and extends the operational lifespan of these devices when exposed to environmental conditions.”
“This progress represents an important step towards high-efficiency, long-lasting solar panels, which will allow more people to access affordable clean energy while reducing dependence on fossil fuels and global carbon emissions.”
