Design and Properties of Titanium Dioxide/Graphene Oxide Composites Exploitable in Wastewater Treatments

Water is one of the necessities for human survival, and clean water is essential for life. As a result, there is an increasing focus on efficient wastewater treatment methods, including advanced oxidation processes using innovative heterogeneous photocatalysts. In this context, TiO2–graphene oxide (TGO) composites offer a multifaceted approach to wastewater treatment, combining the photocatalytic properties of TiO2 with the adsorption capabilities and potential synergistic effects of graphene oxide. In this research, we intimately mixed commercial TiO2 powder with graphene oxide at different concentrations (9, 16, and 25 wt.%) by exploiting sonochemical activation. The morphological and physicochemical analyses confirmed the interfacial interactions and the successful formation of the composite. The TGO composites exhibited increased reactivity compared to both GO and TiO2 phases, during the photodegradation process of Rhodamine B (RhB), serving as a reaction model. Therefore, the photocatalytic results demonstrated the synergistic effect that occurs when a TiO2-based photocatalyst is combined with sonochemically activated GO. The Cu2+ adsorption tests, simulating the removal of heavy metals from contaminated water, revealed that TGO composites displayed intermediate capabilities compared to the pure phases’ higher (GO) and lower (TiO2) adsorption capacity. The functional characterizations revealed that the optimal design is represented by the sample containing 16 wt.% of GO. Overall, this study confirms that TGO composites are effective as photocatalysts and adsorbents for removing both organic and inorganic pollutants, making them strong candidates for wastewater treatment.