Mitigation of Potential‐Induced Degradation in Glass‐Encapsulated Perovskite Solar Cells Using a NiOx Barrier Layer

While the efficiency of perovskite solar cells has been increasing rapidly in recent years, studies on potential‐induced degradation (PID) in these devices have so far been very limited. Herein, the first successful mitigation of PID in glass‐encapsulated perovskite solar cells is reported. A thin NiO x blocking layer between the indium tin oxide and the self‐assembled monolayer is proposed to suppress the PID in these solar cells. Two groups of devices are fabricated, with and without the presence of the NiO x layer. When −1000 V is applied between the short‐circuited solar cell and the front glass pane, the original devices without NiO x only retain about 27% of the initial efficiency, and the modified devices with NiO x retained ≈65% after an extended stress duration of 96 h. The Na + ions from the glass pane occupy NiO x vacancies under high voltage stress and, as a result, the Na x ion migration toward the perovskite layer is heavily suppressed due to the introduction of NiO x . The modified devices also demonstrate good long‐term stability, retaining more than 80% of initial efficiency after the PID stress test. The results of this work are helpful on the journey toward successful commercialization of perovskite solar cells.