Performance enhancement of Cu-based AZO multilayer thin films via graphene fence engineering for organic solar cells

Performance enhancement of flexible transparent conductive Cu-based Al-doped ZnO (AZO) multilayer thin films has been achieved by fence engineering of graphene film. The multilayers show the excellent performance (figure of merit of 3.38 × 10−2 Ω−1, commutation quality factor of 430): sheet resistance of 4.37 Ω/sq., resistivity of 3.98 × 10−5 Ω cm, and average transmittance of above 82% in the visible range, which are the highest values obtained up to now in the flexible transparent conductive films. The commutation quality factor is about four times larger than that of indium tin oxide, the most widely used flexible transparent conductive films today. To assess the application potentials, flexible organic solar cells (FOSCs) are achieved, whose efficiency is 4.63%, which is increased by 95% and 26% compared with the reference FOSCs used a conventional ITO and Cu-based AZO multilayer electrodes, respectively.