Demonstrated photons to electron activity of S-doped TiO 2 nanofibers as photoanode in the DSSC

Abstract 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.