Graphene oxide doping in tropical almond ( terminalia catappa L.) fruits extract mediated green synthesis of TiO 2 nanoparticles for improved DSSC power conversion efficiency

The power conversion efficiency (PCE) of a dye-sensitized solar cell (DSSC) device depends on its semiconductor characteristics. Titanium dioxide (TiO2) nanoparticles are a semiconductor material commonly used in the DSSC device whose characteristics depend on the synthesis process. There are many routes to synthesize TiO2, however, they typically involve hazardous approaches, which may cause risk to the environment. Green synthesis is an environmentally friendly alternative method using ecological solvents that eliminates toxic waste and reduces energy consumption. In this work, tropical almond (Terminalia catappa L.) was used as a natural capping agent in the green synthesis to control the growth of TiO2. In addition, graphene oxide (GO) was used as a dopant to increase the performance of DSSC device. The results are convincing, in which the addition of 0.0017 % GO doping in tropical almond extract mediated green synthesis of TiO2 improved the PCE from 0.85 % to 1.72 %. These results suggest that GO-modified TiO2 nanoparticles green synthesized using tropical almond extract have great potential in the fabrication of DSSC devices with good PCE, low cost, and low environmental impact.