Synthesis of different ZnO nanostructures by modified PVD process and potential use for dye-sensitized solar cells

Different ZnO nanostructures were synthesized by physical vapor deposition on glass-ITO substrates. Nanowires and nanosheets were obtained by a single step process using gold nanoparticles and gold thin films as catalyst. 3D nanoarchitectures were obtained by a two-step modified process; the morphology of these structures depends on the catalyst used for the second deposition: gold nanoparticles or zinc acetate seeds. All the nanostructures were characterized by SEM and TEM analyses, which showed the different morphology under same conditions of temperature, pressure, oxide precursor and deposition time. Dye-sensitized solar cells based on these ZnO structures were successfully assembled, using N179 as sensitizer with efficiencies between 0.1% and 0.5%. In spite of the low efficiency of the cells, a novel double PVD process is presented and its integration capability into solar cell devices has been proven.