Coordination‐Regulated Ultrathin Silver Electrodes for High‐Efficiency Semitransparent Organic Solar Cells

In semitransparent organic solar cells (ST‐OSCs), island‐like growth of ultrathin metal electrodes can lead to electrical and optical losses. Here, we demonstrate that amine‐functionalized perylene diimide (PDINN), a commonly used electron interfacial layer, also acts as a dense nucleation layer for ultrathin silver (Ag) and enables a continuous, smooth film with a lower percolation threshold and higher visible‐light transmittance. Strong PDINN–Ag interactions, with a binding energy of –4.39 eV and adsorption energy of –4.68 eV quantified by density functional theory calculations, significantly regulate Ag nucleation, suppress Ag migration and oxidation, thereby improving the stability of transparent electrodes. By optimizing the deposition rate and integrating a MoO 3 anti‐reflective coating layer, the resulting transparent electrode achieves a low sheet resistance ( R s ) of 6.0 Ω sq −1 , a high average visible transmittance (AVT) of 89.2%, and an outstanding figure of merit (FoM) of 613, together with excellent environmental stability. The ST‐OSC incorporating this electrode reaches a light utilization efficiency (LUE) of 5.12%. This work provides a facile and scalable strategy for fabricating transparent electrodes with high transmittance, conductivity, and excellent stability, advancing the development of next‐generation ST‐OSCs.