The role of graphene oxide content on the adsorption-enhanced photocatalysis of titanium dioxide/graphene oxide composites

Photocatalytic degradation of methyl orange dye by pristine titanium dioxide, zinc oxide, and graphene oxide nanostructures and their composites under visible light irradiation

“…6). While this may support the idea that graphene oxide acts as a charge carrier to reduce the amount of electron recombination, this is a relatively small improvement (Nguyen-Phan et al 2011;Jiang et al 2016). The ratio of GO to the photocatalyst materials may again have an impact, as the composite has a 2:1 ratio of the photocatalyst to GO (Fig.…”

“…6). While there were equal concentrations of the three materials in the composite, increasing the amount of photocatalyst compared to GO could increase photocatalytic activity, while the large surface area of GO could still act as the charge carrier surface (Jiang et al 2015(Jiang et al , 2016Nguyen-Phan et al 2011). Another enhancement in performance could be made by solely combining ZnO and GO, as ZnO was shown to be more efficient than TiO 2 .…”

“…GO may also be interfering physically with the TiO 2 in solution: GO may absorb some of the visible light, resulting in lost light for TiO 2 . GO could also be acting as a recombination platform for TiO 2 instead of a conducting plane for electrons, further worsening photocatalytic performance (Nguyen-Phan et al 2011).…”

“…For example, altering the textural design, doping, and forming semiconductor composites have been examined. One particular focus of research is the utilization of graphene in combination with semiconductor photocatalysts to act as an electron-transfer medium to reduce recombination (Dai et al 2014;Nguyen-Phan et al 2011). There are reports on the performance of nanocomposites of graphene oxide (GO) and TiO 2 ; however, little work has been done with GO-ZnO, GO-TiO 2 at different concentrations, composite ratios, and size.…”

Sulphur, nitrogen-doped TiO2/graphene oxide composites as a high performance photocatalyst

“…Graphene is an atomic sheet of sp 2 bonded carbon atoms that are arranged into a honeycomb structure [27]. Apart from its unique electronic properties, this material with two-dimensional plane structure has several other excellent attributes, such as large theoretical specific surface areas and high transparency due to its one-atom thickness [28][29][30]. However, graphene is poorly soluble in water and polar organic solvents and easily aggregates owing to strong van der Waals force.…”