SYNTHESIS AND CHARACTERIZATION OF GRAPHENE OXIDES TO OBTAIN TiO2/rGO NANOTUBE.
The titanium dioxide (TiO2) has some interesting properties, including non-toxicity, high availability, high cost-effectiveness, good biocompatibility, and good chemical stability, which makes it interesting for applications in several areas. TiO2 nanotube matrices are particularly useful in processes involving photocatalysis such as pollutant degradation, H2 generation and self-cleaning surfaces. However, TiO2 has a restricted photocatalytic efficiency due to its wide bandgap (3.2 eV), which limits its absorption in the ultraviolet radiation region, corresponding to only 4-7% of the solar spectrum radiation. To improve the photocatalytic efficiency of TiO2, many researchers have explored some methods to reduce the bandgap value of this material, among them, the addition of graphene oxide (GO) as a co-adsorbent. GO has a good specific surface area and strong light absorption properties, which can improve the photocatalytic efficiency of TiO2, however, it has many oxygen-containing functional groups, which impair its electronic properties. Therefore, research is aimed at promoting the reduction of GO to reduced graphene oxide (rGO), which has a smaller number of functional groups, thus recovering the electronic properties of the material, such as its mobility of charge carriers. From that, this research was directed towards the synthesis and characterization by various techniques of analysis of the 3-hour graphene oxide, done through the Hummers method modified and improved by the team, and its subsequent reduction on TiO2 nanotubes, using the technique of dip coating for its deposition and later performing the thermal reduction technique in a muffle furnace, of low cost, with different temperature values (400/420/450/470/500/520°C) for 2 and 5 hours.