Ruddlesden–Popper Perovskite for Stable Solar Cells

Three-dimensional metal-halide perovskites have emerged as promising light harvesting materials for converting sunlight to electricity in the last few years. High power conversion efficiency of 23.3% has been demonstrated. However, the main challenge that currently limits the application of the perovskite solar cells is the long-term stability, which has ambient, thermal, and photo stability weaknesses. Recently, the quasi two-dimensional Ruddlesden–Popper perovskites have showed great potential to enhance the stability and achieved an acceptable power conversion efficiency (>13%) compared to the traditional three-dimensional perovskites. The long organic cations in low-dimensional perovskites are more hydrophobic than the typically used short methylammonium cation in three-dimensional perovskites. Here, we summarize recent developments of the Ruddlesden–Popper perovskite solar cells, including Lead-based quasi two-dimensional and Lead-free quasi two-dimensional perovskite structure. The light harvesting performance and charge-carrier dynamics in these perovskite solar cells are reviewed. In addition, critical challenges that limit the performance of Ruddlesden–Popper perovskite solar cells are discussed. Perspectives and future directions are proposed.