Thickness effect of single crystalline TiO2 nanorods for dye-sensitized solar cells.
A hydrothermal method was explored to synthesize single-crystalline (sc) rutile TiO2 nanorods (NRs) with a thickness ranging from 2.4 μm to 6.4 μm on a transparent conductive fluorine-doped tin oxide (FTO) substrate. The variation of precursor ratios in the synthesis solution modulates the length of sc-TiO2 NRs. That is, as the amount of the precursor (titanium butoxide) is decreased in the synthesis bath, the growth length of sc-TiO2 NRs is reduced steadily; the rod diameter is also decreased in the circumstance where all experimental conditions are identical. These samples were applied to dye-sensitized solar cells (DSSCs), the efficiency of which was increased with the thickness of the rods. However, the efficiency of 6.4 μm-thick TiO2 NRs is inversely decreased, resulting from the blocking of pores between NRs from unfavourable electrolyte penetration. These results were confirmed by the incident photon to current efficiency (IPCE).
Soon Hyung
SH
Kang