Enhanced Dye-Sensitized Solar Cell Efficiency of Titanium Oxide (TiO2) -Doped Reduced Graphene Oxide (rGO)

The Titanium Dioxide (TiO
₂
) doped reduced Graphene Oxide (rGO) was introduced as a semiconducting layer of Dye-Sensitized Solar Cell (DSSC). The rGO was prepared by using Hummer method while TiO
₂
doped rGO was prepared by combining Titanium (IV) Oxide nanopowder as precursor of TiO
₂
and chemically reduced oxide rGO. The molarity of rGO was first studied to determine the optimal molarity of rGO for doping process of TiO
₂
from its structural and optical properties. The morphological study shows that the 0.010M of rGO solution is the optimum molarity and has a higher absorbance compared to 0.005M and 0.015M. To determine the optimal organic dye for DSSC application, three different organic dyes with rGO thin film such as turmeric (curcumin), spinach (chlorophyll) and beetroot (anthocyanin) have been studied and the UV-Vis result shows that the chlorophyll pigment from spinach dye has several absorption peaks compared to others. Before fabricating DSSC, the X-ray Photoelectron Spectroscopy (XPS) measurement was conducted to determine the chemical bonding structure of TiO
₂
doped rGO. The results show that the presence of the Ti-O-C structure that indicates some of Ti atoms in TiO
₂
have been substituted by C atom during doping process of TiO
₂
. The results show that rGO doping significantly improves the efficiency of DSSC.