ITO-free inverted polymer solar cells with ZnO:Al cathodes and stable top anodes

► We demonstrate ITO-free, PEDOT:PSS-free inverted polymer solar cells. ► Air stable materials were used for the top anode. ► The ZnO:Al bottom cathode was optimized for good transmission and conductivity. ► The solar cells have 3% efficiency. ► The photocurrents in the inverted structures are higher than in the standard forward, ITO-based cell.