Extensive enhancement in power conversion efficiency of dye-sensitized solar cell by using Mo-doped TiO 2 photoanode

In this work, we have synthesized Mo-doped TiO 2 nanoparticles by sol–gel method and used them as photoanode in dye-sensitized solar cells (DSSCs). Mo doping resulted in reduced TiO 2 crystallite size as revealed from XRD and TEM studies, which caused enhancement in surface area and greater dye loading and hence improved current conversion efficiency of DSSC. The short-circuit current density ( J SC ) and efficiency ( η ) of the cell employing Mo-doped TiO 2 photoanode have been extensively enhanced compared to the cell using un-doped TiO 2 . The optical bandgap ( E g ) for 0.25 wt% Mo-doped TiO 2 and un-doped TiO 2 was obtained as 2.35 eV and 3.04 eV, respectively. The values of J SC and η for the cell employing 0.25 wt% Mo-doped TiO 2 photo-anode were 8.54 mA/cm 2 and 3.78%, respectively, under illumination of 100 mW/cm 2 light intensity (with corresponding values for un-doped TiO 2 4.01 mA/cm 2 and 0.73% respectively under similar illumination condition). Electrochemical impedance spectroscopy (EIS) and Mott–Schottky analyses revealed resistivity, capacitive elements, the donor density, and flat band potential respectively for un-doped and Mo-doped TiO 2 . The work demonstrated that Mo-doped TiO 2 can be used as a photo-anode material for developing low-cost, high-efficiency DSSC.