A Facile Route to Polymer Solar Cells with Optimum Morphology Readily Applicable to a Roll‐to‐Roll Process without Sacrificing High Device Performances

A new fabrication method for polymer solar cells that can produce optimized vertical distribution of components is reported. The favorable donor–acceptor morphology showing a well-organized photo-induced charge transporting pathway with fine nanodomains and high crystallinity is achieved. This process is also readily scalable to a large-area and high-speed roll-to-roll process without sacrificing high device performances, even without a PEDOT:PSS layer.