Study of reduced graphene oxide film incorporated of TiO2 species for efficient visible light driven dye-sensitized solar cell

The hybrid reduced graphene oxide (rGO) with titanium dioxide (TiO2) species photoelectrodes forming a TiO2-rGO nanocomposite (TiO2-rGO NC) was prepared using a simple hydrothermal technique to enhance their visible light dye-sensitized solar cells (DSSCs) performances compared with the pure reduced graphene oxide (rGO) photoelectrodes. This study aims to determine the optimum loading content of TiO2 species on the rGO photoelectrodes for improving their visible response in terms of conductivity as well as photoconversion efficiency. A low content of TiO2 (0.3 wt%) species was successfully incorporated into the rGO photoelectrodes lattice and formed a Ti-O-C bond, which significantly maximized the photocurrent generation efficiency and promoted a charge separation by trapping the photo-induced electrons with 7.2%, which is relatively high compared to the pure rGO photoelectrodes (0.67%). However, the excess TiO2 species of 0.4 and 0.5 wt% resulted in poor photoconversion efficiency performance attributed to the over photocatalytic reaction occurred leaving extra holes on the counter electrode. Herein, a novel hybrid formation between rGO and TiO2 nanomaterials by using the one-step hydrothermal technique in order to improve the DSSCs performance which brought a better conductivity, higher photoconversion efficiency (0.67-7.20%), and lower recombination of rGO material was introduced.