Self-cleaning property of graphene oxide/TiO2 thin film

GO/TiO2 is one of the promising semiconductor materials which are used as photocatalyst in the form of a thin film. The addition of GO into TiO2 possessed a good ability of hydrophilic-hydrophobic interaction. It is also preventing recombination of photo-generated electron hole in the semiconductor due to sufficient formation of charge-carrier mobility. These properties help much in preparing a self-cleaning glass which can be proven by the increment of the rate of percentage removal of pollutants. In this work, GO/TiO2 thin films were prepared by sol gel method at different ratio of titanium (IV) isopropoxide under fixed GO loading. These films were coated onto glass substrate by spin coating technique to get a uniform films followed by annealing process at 350°C for 1 hour under air condition. The effects of different ratio of titanium (IV) isopropoxide with propan-2-ol solvent as well as annealing effect on the samples were characterized based on the wettability of the films and also the photocatalytic activities of GO/TiO2 thin films based on percentage removal of methylene blue (MB) solution under solar irradiation. The results show that the contact angle of GO/TiO2 was increased from 93.14° to 117.55° for higher amount of propan-2-ol for the non-annealed samples. It can be seen that, annealing process had affect the contact angle of the films for both ratios indirectly had improved the removal of dye of the films with 43.87 % for lower propan-2-ol while 38.45% for removal for higher amount of propan-2-ol. This finding indicates that the ratio of the TTIP to propan-2-ol in preparing the thin films were important for the photocatalytic degradation of methylene blue due to the interaction of hydrophilic-hydrophobic of the films for self-cleaning properties application.