Cost-Effective Cathode Interlayer Material for Scalable Organic Photovoltaic Cells

Organic photovoltaic (OPV) cells have demonstrated remarkable success on the laboratory scale. However, the lack of cathode interlayer materials for large-scale production still limits their practical application. Here, we rationally designed and synthesized a cathode interlayer, named NDI-Ph. Benefiting from their well-modulated work function and self-doping effect, NDI-Ph-based binary OPV cells achieve an excellent power conversion efficiency (PCE) of 19.1%. NDI-Ph can be easily synthesized on a 100 g scale with a low cost of 1.96 $ g^-1 using low-cost raw materials and a simple postprocessing method. In addition, the insensitivity to the film thickness of NDI-Ph enables it to maintain a high PCE at various coating speeds and solution concentrations, demonstrating excellent adaptability for high-throughput OPV cell manufacturing. As a result, a module with 21.9 cm² active area achieves a remarkable PCE_active of 15.8%, underscoring the prospects of NDI-Ph in the large-scale production of OPV cells.