Multifunctional TiO2(R)/Fe2O3 Photocatalytic Composites Obtained from Ilmenite Ore

Abstract

AbstractThe commercialization of the photocatalysis technology requires that the synthesis of the photocatalytic material is easy to scale up. Thus, the synthesis from earth‐abundant minerals represents one plausible solution to obtain materials by a scalable process with a lower environmental impact. So far, the most promising photocatalyst for this application is titanium dioxide (TiO2), which can be obtained from ilmenite ore; however, its synthesis usually implies toxic solvents and complicated reaction conditions. Thus, here is proposed an optimized method to extract higher amounts of TiO2 by a multivariable Plackett‐Burman design of experiments considering the mass of the ore precursor, the addition of phosphoric acid (H3PO4), the digestion temperature, the amount of base to adjust the pH, and the final thermal treatment. From this design, it was possible to minimize the heat treatment and the amount of base used to favor higher TiO2 (rutile) content with the presence of additional phases of iron oxides (Fe2O3) that act as co‐catalyst to enhance the photocatalytic activity. The photocatalytic activity of the TiO2/Fe2O3 composites obtained was investigated in four model reactions to obtain solar fuels (H2 evolution and CO2 reduction) and to remove endocrine water pollutants (bisphenol A and dyeing water), using visible and natural solar irradiation, respectively.