Improvement of Amorphous Silicon Thin-Film Photovoltaic Cells with Zinc Oxide Nanorods

In this study, zinc oxide nanorods (ZnO NRs) were produced using a chemical solution method, which was applied to the surfaces of amorphous silicon (a-Si:H) thin-film photovoltaic cells as an anti-reflective layer (ARL). ZnO NRs of different lengths were grown on Si substrates by controlling the growth time. They were then analyzed using an X-ray diffractometer (XRD), UV-vis spectrometer, and field-emission scanning electron microscope (FESEM), thereby obtaining the optimal growth conditions for ZnO NRs. The optimal growth parameters were applied to the surface of a-Si:H thin-film photovoltaic cells. The results show that the short-circuit current density increased from 6.23 mA/cm2 to 8.05 mA/cm2, and the efficiency increased from 3.49% to 4.51%, an increase of approximately 29%. In addition, ZnO NRs growing on the surfaces of a-Si:H thin-film photovoltaic cells can reduce the hydrophilicity. The experimental results show that ZnO NRs have great application potential, not only for improving the conversion efficiency, but also for protecting the devices from external environmental influences.