Graphene-modified TiO2 as photoanode using agarose gel electrolyte for dye-sensitized solar cell

A newly developed biopolymer agarose gel electrolyte along with titanium dioxide-graphene (TiO2−G) as a photoanode in Dye-Sensitized Solar Cell (DSSC) was prepared and investigated towards green approaches and electrolyte stability. To develop a biopolymer electrolyte, potassium iodide was added to the agarose biopolymer matrix to produce a gel electrolyte system. As for the photoanode, TiO2 with different graphene concentrations was prepared. It was recorded that the bandgap was reduced from 3.0 eV to 2.50 eV with the increasing graphene concentration. The formation of agarose gel electrolyte and TiO2−Graphene photoanode were determined by the FTIR analysis. Meanwhile, XRD analysis was conducted to identify the crystallinity of agarose gel electrolyte and TiO2−G affecting the performance of the cell. The XRD spectra measured in a range of 2⊖ from 5° to 80° showed a diffraction peak at 2⊖ = 22°, 25.5° and 36° for agarose gel electrolyte and 2⊖ = 24.88° for TiO2−Graphene. The results illustrated that the TiO2−G combination improves the crystallinity and thus exhibits higher surface area and mesoporous structure for better electrical conductivity and simultaneously strikes the performance stability of DSSC.