PET-based perovskite solar cells to avoid potential-induced degradation

Interest in perovskite solar cells (PSCs) has grown, with advances in stability and scalability for commercialization. However, in real-world conditions, PSCs can encounter potential-induced degradation (PID), primarily due to sodium ion (Na+) migration from conventional soda-lime glass (SLG) substrates. This study investigates whether PID can be completely avoided using Na+-free substrates such as polyethylene terephthalate (PET). PET and SLG-based PSCs were subjected to -1000 V PID stress. The test was conducted in an inert environment to exclude other degradation factors. After 300 h, PET-based PSCs demonstrated only a 0.11% efficiency loss, staying well below the 5% stability threshold, compared to a 15% loss in SLG-based PSCs. The results confirm that using Na+-free substrates effectively prevents PID, and that Na+ migration is the primary cause of degradation during PID stress. These findings support further research to develop PID-resistant PSCs.