HIGH LIGHT-TO-ENERGY CONVERSION EFFICIENCIES FOR SOLAR-CELLS BASED ONNANOSTRUCTURED ZNO ELECTRODES

Photoelectrochemical properties of nanostructured ZnO thin film electr odes have been investigated in the UV and visible regions. For films c onsisting of 15 nm large undoped crystallites a maximum monochromatic current conversion efficiency of 58% was obtained in the visible using a ruthenium-based dye as a sensitizer. The overall solar energy conve rsion efficiency for this film was 2%. In comparison, sensitized films consisting of 150 nm large Al-doped crystallites yield a monochromati c current conversion efficiency of 31% and an overall solar energy con version efficiency of 0.5%. The study also shows that nanostructured Z nO may give high efficiencies in the UV region, approaching unity for the Al-doped films.