Fe–Zn–Ti combined systems as photocatalysts for hydroxyl radicals production in sunlight

• Published in: International journal of hydrogen energy 2022-08, Vol.47 (74), p.31888-31902
• Main Authors: Cruz Santiago, Lorenzo Antonio, Martínez Salazar, Ana Lidia, Vega Moreno, Jesús, Reséndiz Hernández, Omar, Portales Martínez, Benjamín
• Format: Article
• Language: English
• Subjects: Anatase; Hydroxyl radicals; Partial oxidation; Sunlight; ZnO; α–Fe2O3
• ISSN: 0360-3199; 1879-3487
• DOI: 10.1016/j.ijhydene.2022.02.203

In this research, we focused on a photocatalyst for hydroxyl radicals (•OH) production in sunlight and proposed to extend TiO2 photocatalytic capacity to a visible range by combining it with oxides derived from metals such as iron and zinc. The systems were synthesized through the sol-gel method and were characterized by TGA, FTIR-ATR, XRD, Raman, XPS, UV–Vis, and •OH quantification was carried out by disodium terephthalate hydroxylation reaction. Two key annealing temperatures of 400 and 800 °C, were detected by TGA studies. The iron-systems treated at 400 °C show the best balance between •OH production and less degradation effect attributed to staggering bands potentials of α–Fe2O3, ZnO, and anatase phases detected by XRD, making them a good option for partial oxidation. On the other hand, the 800 °C treated systems have the worst •OH production due to some phases with narrow bandgap promoting a fast charge carriers recombination. [Display omitted] •Binary and ternary systems of Fe–Zn–Ti were obtained by the sol-gel method.•Iron-systems at 400 °C shows the best balance between.•OH production/degradation.•Iron-systems at 800 °C promotes a fast charge carriers recombination.•Iron-systems at 400 °C are a good option for partial oxidation processes.•Above 400 °C treatment, additional phases are formed and reduce catalytic yield.