Halide perovskite solar cells with mixed-cation compositions often face instabilities under continuous illumination due to the deprotonation of methylammonium (CH3NH3+, MA+) cations. To address this issue, researchers from Tsinghua University, National Renewable Energy Laboratory (NREL) and Princeton University have evaluated the partial and complete deuteration of MA+ cations.
This approach inhibits deprotonation and degradation, reduces the formation energy of the perovskite phase, improves grain growth, passivates defects, and restrains ion migration. As a result, perovskite solar cells incorporating this deuteration strategy achieved exceptional performance, including a high fill factor (FF) of 82.6% and a power conversion efficiency (PCE) of 25.6%.
The modules, with a device area of 56 cm2, demonstrated remarkable stability, maintaining over 93.7% of their initial PCE after 1,000 h at the maximum power point under continuous illumination at 40°C.
This novel deuteration strategy presents a promising approach to enhancing both the efficiency and stability of perovskite solar cells.
