Spatial Atomic Arrangement of Cyclohexyl‐Based Ligands for Enhanced Interface Passivation in 2D/3D Perovskite Solar Cells

Abstract Metal halide perovskite solar cells (PSC) have emerged as a promising candidate for next‐generation photovoltaic technologies, achieving remarkable power conversion efficiencies (PCE) in polycrystalline thin‐films. Nonetheless, their PCE and long‐term stability are often limited by a high density of defects at interfaces and grain boundaries. One effective strategy to mitigate these issues is forming 2D/3D heterojunction structure by introducing a surface‐passivating interfacial layer of quasi‐2D Ruddlesden–Popper perovskite (RPP) with various functional ligand molecules. In this study, hydroxyl‐functionalized cyclohexyl ammonium hydrochloride (ACHACl) is employed as the ligand molecule, which features dual functional groups. A comparative analysis reveals that cis‐configurations of the ligands exhibit enhanced adsorption on the [PbI6]4− octahedra in lead halide perovskites, ena…