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

Perovskite solar cells (PSCs) have been continuously breaking the photoelectric power conversion efficiency (PCE) record, while effective large-area manufacturing and high device stability are two long-standing challenges toward commercialization. Here, we report a green additive of N-methyl-2-piperidone (N1) to modify the perovskite precursor, enabling the one-step manufacturing 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 PbI2, the generated PbI2-N1 complex can effectively prevent the preferential nucleation and realize lead halide-framework template-assistant crystallization reaction with organic cation in the one-step solution preparation of perovskite (FAPbI3)0.95(MAPbBr3)0.05 thin films, which result in the uniform grain size and smooth, dense film quality. Therefore, the PSC device with small active area of 0.09 cm2 exhibits an efficiency of 22.2 %, which is further improved to 23.2 % by passivating the perovskite interface using 2-Phenylethylamine hydroiodide (PEAI). Moreover, highly efficient slot-die printed 5 × 5 cm2 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.