Silver-coated TiO2 electrodes for high performance dye-sensitized solar cells

• Ag-coated TiO2 electrodes were prepared by photo deposition method.
• The conversion efficiency was improved from 5.97% to 6.86%.
• The Ag layer can lengthen the optical path in electrodes.
• Charge transfer from surface states has been strongly suppressed.

Silver-coated TiO2 electrodes were prepared by photodeposition with different light durations. Comparing with the dye-sensitized solar cells (DSSCs) using conventional TiO2 electrode, the conversion efficiency of DSSCs fabricated with silver-coated TiO2 electrodes was improved from 5.97% to 6.86%. The Ag layer could reflect incident light and lengthen the optical path in electrodes, and also appropriate Ag particles absorbed on the TiO2 surface slowed down the electron recombination. The recombination mechanisms of DSSCs were analyzed by open circuit voltage decay (OCVD) measurements, which provide evidence that the charge transfer from the surface state was strongly suppressed by the silver coating.