Effect of titanium coating on the structural and optical properties of TiO2 thin films for improved performance in dye-sensitized solar cells

Abstract

In favor of enhancing the performance of TiO2 photoanode-based dye sensitized solar cells (DSSCs), a thin layer of titanium was coated on Indium doped tin oxide (ITO) conductive glass substrate prior to the coating of TiO2 by using sol-gel spin coating technique. Titanium coating was obtained by DC sputtering method using titanium target and its effect on the structure, morphology of TiO2 and the photovoltaic properties of the subsequent DSSCs were studied. Porous morphology was observed in the TiO2 film with titanium coating. The photoelectric conversion efficiency of DSSC based on TiO2 with titanium coating is larger than that without titanium coating. An efficiency of 3 % was obtained for titanium coated TiO2 electrode. The improvement of the solar cell may be due to the increase in dye adsorption of TiO2 thin film with titanium coating. In this work, the novelty lies in the role of titanium which is for the first time coated beneath the TiO2 film resulting in the improved structure and morphology of the photo anode and thereby an enhanced DSSC efficiency.