Heterocyclic Molecular Passivators for Improved Stability and Efficiency in Perovskite Solar Cells

In recent years, organic–inorganic halide perovskite solar cells (PSCs) have rapidly emerged as one of the most promising third‐generation photovoltaic technologies, due to their high‐power conversion efficiency (PCE), low cost, and solution processability. The device performance and PCE depend on the architecture of PSCs and interfacial properties. Further, improvements in PCE are largely driven by minimizing nonradiative charge recombination, often caused by defects in metal halide perovskites. This review focuses on how heterocyclic compounds containing N, O, S, NS, and NO, affect grain boundaries, inhibit nonradiative recombination, and improve photovoltaic performance as molecular passivators. Finally outlines, the guidelines for selecting suitable heterocyclic compounds as passivating agents and offers perspectives on future strategies to further advance passivation approaches and overall device performance.