Demonstrated photons to electron activity of S-doped TiO₂ nanofibers as photoanode in the DSSC

S-doped TiO₂ nanofibers are introduced as a novel photoanode in the DSSC. The proposed anode was fabricated by electrospinning of poly(vinyl acetate)/titanium isopropoxide sol-gel followed by calcination at 500 °C. Afterward, the obtained TiO₂ nanofibers were hydrothermally treated in dimethyl sulfoxide at 180 °C for 18 h. SEM, TEM images revealed good morphology, and surface holes-containing nanofibers. XRD analysis emphasized on the unnecessity of excessive calcination temperature because that would convert the anatase TiO₂ to the undesirable rutile phase. XPS technique concluded the presence of S atoms with an oxidation state of +6. These atoms are attached to the surface and inside the lattice of the TiO₂ nanofibers. As an anode in the DSSC, the treated nanofibers showed very good performance compared to the untreated ones. Typically, 4.27% and 1.54% solar-to-electrical energy conversion was obtained from the DSSC having the treated and untreated TiO₂ nanofibers, respectively.