Magnetic self-doped TiO2−x/Fe3O4@g-C solar-driven photocatalytic composite for water decontamination

Abstract

Declining water resources and their contamination with chemicals risk the aquatic environment. Therefore, this work was devoted to designing a magnetically recyclable photocatalyst suitable for water treatment, namely, a TiO_2−x/Fe₃O₄@g-C composite. Different preparation conditions were investigated together with the corresponding characteristics. The pure defective anatase TiO_2−x phase of low band gap energy was detected through XRD and DRS analyses. Low charge recombination after the formation of defects was confirmed. The performances of the prepared photocatalysts in phenol degradation under solar light were evaluated, revealing the superior efficiency of TiO_2−x prepared hydrothermally at 200 °C/24 h relative to intact TiO₂. This best sample was incorporated with Fe₃O₄@g-C to facilitate its recovery and reuse. This successful combination was confirmed using XRD, Raman and XPS tools. TiO_2−x/Fe₃O₄@g-C 2 : 1 formulation was found to be the most photoactive and could be reused up to five times without significant loss in its efficiency. Therefore, the precisely developed magnetic photocatalyst is promising for application in the water-treatment process.