Pyridine solvent engineering for high quality anion-cation-mixed hybrid and high performance of perovskite solar cells

Organic-inorganic hybrid perovskite solar cells have become dominant topics on photovoltaic field in the past decade. The quality of the perovskite layer plays a crucial role in the photovoltaic performance of perovskite devices, and the solvent engineering is an attractive method for improving the quality of perovskite layer. Here, we introduce pyridine additive in the precursor mixed solution to prepare high quality cation-anion-mixed perovskite of CS0.05 (MA(0.17)FA(0.83))(0.95)Pb(I0.83Br0.17)(3). The morphology observation indicates that a large grain, dense and pinhole-free perovskite film is obtained by pyridine adding. Photoluminescence and resistance measurements demonstrate that pyridine adding contribution to less defects and charge carrier recombination in the perovskite layer. The perovskite solar cell with pyridine adding achieves a power conversion efficiency of 19.03%, while the device without pyridine adding reaches an efficiency of 16.94% at the same experiment conditions. The simple and green procedure and significant improvement in the performance render this method promising.