An international team led by the University of Surrey with Imperial College London has identified a strategy to improve both the performance and stability of solar cells made from perovskites by mitigating a previously hidden degradation pathway.

In a new study published in Energy and Environmental Science, the researchers said they could produce lead-tin perovskite solar cells that reach 23.2% power conversion efficiency – one of the best results achieved with this material.

More importantly, they were able to design a strategy that improves the lifetime of these devices by 66%.

While perovskite/silicon solar panels with high efficiencies are emerging on the market, for this technology to be commercially viable, scientists must tackle the challenge of improving both the stability and efficiency, especially around the lead-tin perovskite cell used in this design.

This research study identified previously hidden mechanisms that contribute to both efficiency and stability losses and addresses these challenges, helping the scientific community to advance this technology.

Perovskites, a class of crystalline materials, are known for their exceptional ability to absorb sunlight and convert it into electricity. Unlike conventional silicon-based solar cells, perovskites are lightweight, cost-effective, and highly efficient under low-light conditions.

However, their susceptibility to instability, short lifespan, and environmental concerns regarding lead content have limited their large-scale application, so the researchers employed a novel cyanogen management strategy to address these limitations. The material combines organic and inorganic components, creating a hybrid system that enhances the overall performance of solar cells by improving light absorption and reducing energy losses due to defects in the material.

With a low band gap, this material allows the solar cells to absorb more sunlight, especially in low light conditions, making them more versatile and efficient than previous versions.

Hashini Perera, lead author of the study, said, “The understanding we have developed from this work has allowed us to identify a strategy that improves the efficiency and extends the operational lifetime of these devices when exposed to ambient conditions. This advancement is a major step towards high efficiency, long-lasting solar panels which will give more people access to affordable clean energy while reducing the reliance on fossil fuels and global carbon emissions.”

Earlier this year, researchers from Monash University, the University of Oxford, and the City University of Hong Kong created a “self-healing” mechanism for perovskite solar cells. Their development led to a perovskite solar cell with 25.1% power conversion efficiency and significantly improved long-term stability.

In September, researchers from the Huazhong University of Science and Technology in China developed an all-perovskite tandem solar cell with a record power conversion efficiency of 28.49%.