Influence of growth acidic solution and etching time on rutile TiO2 nanorod arrays synthesized by hydrothermal method in dye-sensitized solar cells

Titanium butoxide (Ti(OBu)4) precursor was used to prepare titanium dioxide (TiO2) nanorods as a photoanode by hydrothermal method directly on FTO glass with different hydrochloric acid (HCl) – water (H2O) ratio (12.5-7.5, 10-10, 7.5-12.5 and 5-15) ml and etching times (24, 48, and 72)h. The (XRD) results show good crystallinity of TiO2 with rutile phase and preferred orientations (101) and (002) for all samples. The grain size of the TiO2 nanorods increases with decrease the HCl concentration. The (FESEM) images show that an increase in HCl concentration leads to an increase in the rod diameter of the TiO2 NRs and a decrease in their length. The optimum efficiency (η) of DSSC based on TiO2 NRs was 3.255% at sample ET, where the preparation condition (7.5 ml HCl + 12.5 H2O) with a 48 h etching time.