Figure 7: Photocurrent density-voltage (J-V) curves for dye-sensitized solar cells using: (a) Commercial TiO2 –P25 (b) bare TiO2 nanocrystals, (c) doped 2% Bi-TiO2 nanocrystals, (d) doped 5% Bi-TiO2 nanocrystals, (e) doped 2% Bi-TiO2 nanocrystals in GO and (f) doped 5% Bi-TiO2 nanocrystals in GO.