High‐Efficiency Perovskite/Silicon Tandem Solar Cells with Flexibility

Perovskite/silicon tandem solar cells are a novel class of solar cells that have recently attracted increasing attention due to their notable efficiency; however, they inherently suffer from loss of flexibility. Accordingly, in this study, we develop flexible perovskite/silicon tandem solar cells by fabricating perovskite solar cells atop bendable thin‐crystalline silicon solar cells. By reducing the thickness of the silicon substrate to approximately 60 µm, applying microtexturing to its surface, and incorporating a low‐refractive index‐doped layer, we produce a flexible silicon heterojunction solar cell with an efficiency exceeding 21%. Subsequently, by optimizing the self‐assembled monolayer processing conditions on the microtextured surface and constructing an inverted perovskite solar cell on the flexible SHJ, we achieve 26.5% efficiency for the flexible perovskite/silicon tandem solar cell. These findings could be valuable for the development of new, highly efficient, lightweight, and flexible solar cells, potentially accelerating their deployment in conditions where traditional silicon solar cells are impractical.