Novel Green Solvent for Sustainable Fabrication of Quasi‐2D Perovskite Solar Cells

Despite the remarkable advances in the field of perovskite photovoltaics, the use of toxic solvents for their fabrication poses a significant challenge to their scale‐up and commercialization. The vast majority of studies rely on using the highly hazardous N, N‐Dimethylformamide (DMF), with green alternatives remaining scarce. In this work, the use of glycerol formal (Gly‐F) is reported as a green solvent for fabricating quasi‐2D ( n = 5) perovskite solar cells. Quasi‐2D perovskite films processed from Gly‐F exhibit a high degree of uniformity and a compact microstructure. When integrated into solar cells, the green solvent‐processed films reach a promising power conversion efficiency of 14.53%. This performance is lower than that of DMF‐based perovskites, most likely due to the presence of laterally oriented low n perovskite phases. Interestingly, while the performance of DMF‐based devices is rather irreproducible, the performance of Gly‐F‐based devices is robust and consistent. These results demonstrate the potential of Gly‐F‐ as a promising green alternative to DMF.