Optical and Electronic Contributions in Double‐Heterojunction Organic Thin‐Film Solar Cells

Combinatorial studies of organic thin‐film photovoltaic cells (see Figure) can identify the separate optical and electronic contributions to the photocurrent. A second charge‐transfer zone is proposed to explain the observed augmentation of the short‐circuit current induced by an additional TiO 2 layer. The ratio of the exciton diffusion lengths in copper phthalocyanine (CuPc) and a perylene dye (DMPTI) is estimated to be ≈ 8:5.