Improved performance of dye sensitized solar cells using Cu-doped TiO2 as photoanode materials: Band edge movement study by spectroelectrochemistry

- Cu-doped TiO2 semiconductors were prepared and applied in DSSCs.
- Band edge movement of Cu-doped TiO2 was investigated by spectroelectrochemical.
- The DSSC based on 1.0 at.% Cu-TiO2 exhibited higher Jsc and η.
- Doping TiO2 with Cu is a promising way to achieve improvements in DSSCs performance.

Cu-doped TiO2 nanoparticles are prepared and used as semiconductor materials of photoanode to improve the performance of dye sensitized solar cells (DSSCs). UV-Vis spectroscopy and variable temperature spectroelectrochemistry study are used to characterize the influence of copper dopant with different concentrations on the band gap energies of TiO2 nanoparticles. The prepared Cu-doped TiO2 semiconductor has avoided the formation of CuO during hydrothermal process and lowered the conduction band position of TiO2, which contribute to increase the short circuit current density of DSSCs. At the optimum Cu concentration of 1.0 at.%, the short circuit current density increased from 12.54 to 14.98 mA cm−2, full sun solar power conversion efficiencies increased from 5.58% up to 6.71% as compared to the blank DSSC. This showed that the presence of copper in DSSCs leads to improvements of up to 20% in the conversion efficiency of DSSCs.

The performance of dye sensitized solar cells could be improved using Cu-doped TiO2 as photoanode materials.46