Relationship between the morphology of poly(3-hexylthiophene)/methanofullerene composite and its photoelectrode characteristics in the water phase

► The photoelectrode of the p/n composite showed only anodic characteristics. ► The composite formation at the substrate was confirmed through a microscopic image. ► The specified charge transfer was due to most of the p-type polymer near the surface. ► Supporting the morphology, the photoanodic output was enhanced by loading a catalyst.