defects

Scientists in the UK delved deep into the structure of a perovskite solar cell, looking to understand the complex relationship between the materials that make up the perovskite layer, and the role of different defects in both limiting and improving performance. The findings could allow for new perovskite materials that are specially structured to maximize PV performance.

An international team of scientists fabricated perovskite solar cells which retained almost all of their initial 21% efficiency after 1,000 hours under continuous operation at their maximum power point. The researchers credit this performance to their discovery of an additive that served to ‘block’ ions that cause device degradation, and also hope their work will contribute to an improved understanding of the relationship between efficiency and stability in perovskite PV.

Scientists in China took a closer look at the role of defects in limiting the performance of perovskite solar cells, demonstrating a screening effect that could be tuned to make material defects “invisible” to charge carriers, greatly improving cell performance. Using this approach they demonstrate a 22% efficient inverted perovskite solar cell, and theorize several new pathways to even higher performance.

A research group in Okinawa, Japan has been able to observe and characterize structural defects in an organic-inorganic perovskite solar cell. Their findings could help to inform future approaches to optimizing and improving perovskite stability.