Solution processed optical modulated silver nanowire top electrode for high performance semi‐transparent organic solar cells

Abstract Silver nanowire (AgNW) top electrodes are pivotal candidates for solution‐processed, semi‐transparent organic solar cells (ST‐OPVs). However, their light utilization efficiency (LUE) typically lags behind that of devices using evaporated metal electrodes, primarily due to the lack of effective optical modulation strategies compatible with solution processing. Guided by rigorous three‐dimensional optical simulations, we developed a fully solution‐processed optical coupling layer (OCL) strategy to bridge this gap. By integrating a spin‐coated polymethyl methacrylate layer atop a sandwich‐structured AgNW composite electrode, we constructed a high‐low refractive index interface that redistributes the optical field. This architecture enhanced the average visible transmittance from 52.2% to 54.8% while simultaneously boosting the short‐circuit current density ( J SC ) from 18.1 to 19.6 mA cm −2 by mitigating reflection losses and parasitic absorption in the near‐infrared region. Consequently, the optimized device achieved a power conversion efficiency of 8.15% and an LUE of 4.47%. To the best of our knowledge, this represents the highest performance reported for all‐solution‐processed ST‐OPVs. Furthermore, this method demonstrates excellent mechanical compatibility with flexible substrates, paving the way for the scalable fabrication of high‐performance, fully solution‐processed flexible photovoltaics.