Modified Antisolvent Method for Improving the Performance and Stability of Triple-Cation Perovskite Solar Cells

Antisolvent crystallization is known as an effective approach for the deposition of pinhole-free solution-processed perovskite layers for high-performance solar cells. Here, we introduce a modified antisolvent dripping method by adding tetra ethyl orthosilicate (TEOS) into chlorobenzene as a conventional antisolvent. Through TEOS modification, perovskite solar cells show efficiencies as high as 16% with more than 85% retention after 290 h storage at ambient conditions in comparison to 20% in pristine cells. This significant enhancement in efficiency and stability mainly related to the decrement of the density of surface defects, which is confirmed by considerably enhanced photoluminescence of perovskite layers. Also, electrochemical impedance spectroscopy results show lower charge recombination at interfaces in modified cells. Regarding the obtained results, our modified antisolvent approach is a simple and promising route to prepare high-quality perovskite layers for solar cell applications.