Recent Progress in Aromatic‐Diimide‐Based Cathode Interlayer Materials for Organic Solar Cells

Abstract Organic solar cells (OSCs), as a third‐generation photovoltaic technology, have now achieved power conversion efficiencies exceeding 21.0%, reaching the commercialization threshold. This great progress is largely attributed to​ innovations in materials design. ​Aromatic diimides (ADIs), as electron‐accepting moieties, ​are extensively studied in OSC research​ owing to their high electron affinity, superior electron mobility, and ​facile​ chemical modification. ​Notably, over the past 3 years, ADI‐based molecular designs have dominated the development of cathode interlayer materials (CIMs), enabling the breakthrough of OSC efficiencies. Therefore, this review ​comprehensively surveys​ recent advances in ADI‐based CIMs, including naphthalene diimides, perylene diimides, and their fused structures. ​Finally, future development trends and practical prospects are discussed​ for these materials, ​aiming to elucidate​ the critical role of ADI‐based CIMs in advancing OSC technology and ​inspire​ future innovations in the field.