Europium doped TiO₂: an efficient photoanode material for dye sensitized solar cell

Globally research on to tailoring the novel materials using II–VI elements aims to improve the dye sensitized solar cells (DSSC) performance. Rare earth elements too are being explored as dopant to metal oxides for such applications. In this work, an effort is made to synthesize europium doped titanium oxide with sol–gel method at different atomic concentrations of Eu ranging from 2.17 × 10¹⁶ to 17.4 × 10¹⁶ atoms/cm³ in the solid mixture. Titanium isopropoxide was hydrolyzed, mixed with Eu precursor and then refluxed followed by drying and calcination of the precipitate that was then used for DSSC fabrication. The particle size was found to vary from 100 to 200 nm with Eu doping while absorption was found increasing with Eu doping concentrations. The photocurrent-voltage characteristics were measured with a simulated light source and a source-meter as a function of Eu doping concentration. It is found that increasing Eu doping concentration enhances the optical absorbance/fluorescence and hence increased photoconversion efficiency. On addition of least amount of Eu, a 1.6 times higher efficiency is noted than that of undoped TiO₂. The proposed study indicated that such controlled doping would have potential in tailoring the material for DSSC and deliver better performance.