Stabilizing Perovskite Solar Cells to IEC61215:2016 Standards with over 9,000-h Operational Tracking

Summary

The stability of perovskite solar cells (PSCs) has been considered as the largest obstacle to their commercialization. Herein, we observed that the main failure mechanism for MAPbI₃ perovskite is the escape of methylammonium (MA) iodide at the grain boundaries in an open space or the reconstruction of crystal in a confined small space, as well as the irreversible long-distance ionic migration under the multiple actions of light, heat, and electrical bias. Strengthened with bifunctional organic molecular of 5-ammoniumvaleric acid (5-AVA) iodide at the grain boundaries, the MAPbI₃ crystal was localized in the nanoscale, and thus, the decomposition or reconstruction was inhibited and the ionic migration became reversible. As a result, we propose a reliable approach to make PSCs meet stability standards of IEC61215:2016 qualification tests. A printable PSC filled with (5-AVA)_XMA_1-XPbI₃ has been working for more than 9,000 h at a maximum power point of 55°C ± 5°C without obvious decay.