Improved photovoltaic performance of nanostructured solar cells by neodymium-doped TiO2 photoelectrode

Abstract Well-crystallized TiO 2 and neodymium (Nd)-doped TiO 2 nanoparticles with various doping levels were synthesized by hydrothermal method and utilized as the photoanode of nanostructured solar cells. The results indicated that Nd-doping was caused the absorption spectra shift to higher wavelength while the morphology and surface area were unchanged. As a result, by employing 0.4 mol% Nd in the TiO 2 photoelectrode, the overall conversion efficiency of the cell reached 9.08% which is 26% higher than pure one. Based on the photo-electrochemical characterizations, the improvement is a consequence of electrons injection increment from dye to TiO 2 conduction band, charge collection efficiency enhancement, and trap states density reduction in the Nd-doped photoanode.