Green N1 additive modified perovskite precursor enables effective manufacturing of large-area solar cell modules with high efficiency and stability

Although the record power conversion efficiency (PCE) of perovskite solar cells (PSCs) has been continuously boosted, the effective large-area manufacturing and good device stability are the major challenges toward their commercialization. Here, we report a green additive of N-methyl-2-piperidone (N1) to modify the perovskite precursor, enabling the one-step fabrication of high-quality large-area perovskite films with enhanced PCE and stability. The results show that due to the stronger complexation ability of N1 additive with PbI 2 , the generated PbI 2 -N1 complex can effectively control the nucleation and growth of perovskite to realize lead halide-framework template-assistant crystallization reaction with organic cation in the one-step solution preparation of (FAPbI 3 ) 0.95 (MAPbBr 3 ) 0.05 , leading to the homogeneous pinhole-free perovskite films with few defects. Therefore, the PSC device with small active-area of 0.09 cm 2 exhibits an efficiency of 23.2 %. Moreover, highly efficient slot-die printed 5 × 5 cm 2 PSC module has been obtained with a champion PCE of 21 % and improved device stability over 1000 h. This work demonstrates a new strategy to realize high-quality large-scale perovskite films for solution-processed PSC modules, which may be further improved and extended to other kinds of PSCs and applications such as perovskite light-emitting diodes and detectors.