Fabrication of flexible dye-sensitised solar cells with photoanodes composed of periodically aligned single crystalline vertical ZnO NRs by utilising a direct metal transfer method

Flexible dye-sensitised solar cells (DSSCs) with photoanodes composed of periodically aligned ZnO NRs were fabricated. The Zn metal dot array as seed spots for ZnO growth was defined on an ITO/PET flexible substrate by a non-aqueous direct metal transfer method. A low-temperature hydrothermal method produced periodically aligned single crystalline vertical ZnO NRs, which expedited electron transport and released bending strain efficiently. The power conversion efficiency was 3.15%, and the device performance was well maintained after 500 bending cycles. A DSSC with photoanodes of nonaligned ZnO NRs was also prepared, and the photoelectric properties were directly compared with those of a DSSC with well-aligned ZnO NRs.