Effects of gold nanoparticles inlaid in the photo-electrode on the properties of dye-sensitized solar cells

• The effect of gold nanoparticles can increase the conductivity and reduce the recombination of charges in the photo-electrode.
• The light-scattering structure can enhance light transmission path in TiO2 films and the absorption of photons.
• Gold nanoparticles result in the increase of the photoelectric conversion efficiency for DSSCs.

In this study, we prepared gold nanoparticles by electrochemical synthesis and inlaid in the photo-electrode of dye-sensitized solar cells (DSSCs) to study the surface plasma resonant (SPR) and light-scattering effects on the properties of dye-sensitized solar cells. The analyses of field emission scanning electron microscopy (FE-SEM) show that the average diameter of gold nanoparticles is 50 nm. The results of ultraviolet–visible absorption spectra show that the absorption wavelength is about 533 nm for gold nanoparticles. The conversion efficiency with different amounts of gold nanoparticles in TiO2 photo-electrodes is 5.42%, 5.92%, 6.06%, and 5.51% with the amounts of 0 μL, 300 μL, 400 μL, and 500 μL, respectively. The best conversion efficiency of the dye-sensitized solar cells with gold nanoparticles added is 6.06%, and is higher than that the cells without gold nanoparticles, which is 5.42%. In addition, in order to study light-scattering effects on the photo-electrode, different thicknesses of large particle size TiO2 (~ 250 nm) coated onto photo-electrode to form double layer structure. The best conversion efficiency of the dye-sensitized solar cells with gold nanoparticles added and with the thickness of 3.3 μm light scattering layer is 7.10%, which is higher than that of the cell without light-scattering layer, which is 6.06%. This result indicates that the effect of gold nanoparticles on the photo-electrode can increase the conductivity and reduce the recombination of charges in the photo-electrode, and the light-scattering structure can enhance light transmission path in TiO2 films and the absorption of photons in the photo-electrode, resulting in the increase of the photoelectric conversion efficiency for DSSCs.

The addition of gold nanoparticles leads to a linear increase in conversion efficiency of the DSSC. When the volume of added gold nanoparticles is 500 μL, the Jsc begins to decrease.Figure optionsDownload as PowerPoint slide