Comparative Analysis of the Stability and Performance of Double-, Triple-, and Quadruple-Cation Perovskite Solar...

The solar energy market is predicted to be shared between Si solar cells and third-generation photovoltaics in the future. Perovskite solar cells (PSCs) show the greatest potential to capture a share there as a single junction or in tandem with silicon. Researchers worldwide are looking to optimize the composition of the perovskite film to achieve an optimal bandgap, performance, and stability. Traditional perovskites have a mixture of formamidinium and methyl ammonium as the A-site cation in their ABX₃ structure. However, in recent times, the use of cesium and rubidium has become popular for making highly efficient PSCs. A thorough analysis of the performance and stability of double-, triple-, and quadruple-cation PSCs under different environmental conditions was performed in this study. The performance of the device and the films was analyzed by electrical measurements (J-V, dark J-V, EQE), scanning electron microscopy, atomic force microscopy, photoluminescence, and X-ray diffraction. The quadruple-cation device with the formula Cs_0.07Rb_0.03FA_0.77MA_0.13PbI_2.8Br_0.2 showed the highest power conversion efficiency (PCE) of 21.7%. However, this device had the least stability under all conditions. The triple-cation device with the formula Cs_0.1FA_0.6MA_0.3PbI_2.8Br_0.2, with a slightly lower PCE (21.2%), was considerably more stable, resulting in about 30% more energy harvested than that using the other two devices during their life cycle.