Novel synergistic combination of Cu/S co-doped TiO_2 nanoparticles incorporated as photoanode in dye sensitized solar cell

摘要

Novel sol-gel route was adopted for the synthesis of undoped and Cu/S co-doped TiO2 nanoparticles (NPs) with constant content 0.05 at% of non-metal Sulfur and diverse content from 0.1 to 0.5 at% of metal Copper. The formation of anatase TiO2 crystalline phase was observed from XRD results with the crystallite size less than 11 nm for all the synthesized samples. The UV-Vis analysis revealed that co-doping with Cu/S altered the optical properties of TiO2 and extended absorption in the visible light region with red shift in band gap energies. EDAX analysis confirmed the purity of Cu/S co-doped TiO2 nanoparticles and also the evident presence of titanium, oxygen, copper and sulfur atoms in stoichiometric ratio. In photovoltaic measurements, under simulated solar irradiation the DSSC based on Cu/S co-doped TiO2 with 0.3 at% Cu and 0.05 at% S has exhibited the best power conversion efficiency (PCE) of 10.44% with significantly improved short circuit current density (J(sc)) of 22.05 mA/cm(2). This enhanced PCE is attributed to the appropriate particle size, enhanced surface area, higher dye adsorption and hence improved short circuit current density (J(sc)). In contrast, the undoped TiO2 NPs based DSSC has displayed a PCE of 6.37% with J(sc) of 14.85 mA/cm(2).