Inorganic CsPbI3 Perovskite‐Based Solar Cells: A Choice for a Tandem Device

Hygroscopicity risk and organic–inorganic hybrid perovskites easy decomposition in solar cells limit their usefulness. Apart from the hybrid organic–inorganic perovskites, inorganic perovskite solar cells display a better stability toward moisture, light soaking, and thermal stressing. However, most inorganic perovskites are inappropriate for single junction or tandem solar cells due to their large bandgaps (>1.8 eV), which eventually results in light absorption loss. Fortunately, cubic CsPbI 3 perovskite (having 1.73 eV bandgap) could potentially serve as top cells in tandem devices with silicon solar cells. Poor phase stability of CsPbI 3 is considered a major obstacle to design CsPbI 3 perovskite solar cells. This review highlights the most recent studies on the progress in CsPbI 3 ‐based solar cell device field. Moreover, this review also summarizes certain strategies to improve phase stability, such as size reduction to nanocrystal or external cations/anions doping, with the aim to improve the devices design.