Solmaz Feizpoor1, Aziz Habibi-Yangjeh2. 1. Department of Chemistry, Faculty of Science, University of Mohaghegh Ardabili, P.O. Box 179, Ardabil, Iran. 2. Department of Chemistry, Faculty of Science, University of Mohaghegh Ardabili, P.O. Box 179, Ardabil, Iran. Electronic address: ahabibi@uma.ac.ir.
Abstract
Herein, novel magnetic TiO2/Fe3O4/CoWO4 nanocomposites were fabricated using a simple refluxing method followed by a calcination step at 450 °C. Photocatalytic activity of these nanocomposites were studied by decomposing rhodamine B, methyl orange, and fuchsine dye contaminants under visible-light illumination. Among the fabricated photocatalysts, the TiO2/Fe3O4/CoWO4 (30%) photocatalyst exhibited superior activity. The degradation rate constant for rhodamine B by this ternary nanocomposite was 8.5 and 5.6 folds greater than those of the pure TiO2 and TiO2/Fe3O4 photocatalysts, respectively. Trapping experiments showed that superoxide anion radicals played critical role during the photocatalytic process. Visible-light harvesting due to the presence of CoWO4 and effective suppression of the charge carriers from recombination due to formation of p-n heterojunction are the major parameters affecting the photocatalytic activity. Furthermore, the TiO2/Fe3O4/CoWO4 (30%) photocatalyst displayed highly stable recycling performances. The present study provides a new strategy to design and fabricate magnetically recoverable photocatalysts based on TiO2 with considerable activity under visible-light.
Herein, novel magnetic n class="Chemical">TiO2/n class="Chemical">Fe3O4/CoWO4 nanocomposites were fabricated using a simple refluxing method followed by a calcination step at 450 °C. Photocatalytic activity of these nanocomposites were studied by decomposing rhodamine B, methyl orange, and fuchsine dye contaminants under visible-light illumination. Among the fabricated photocatalysts, the TiO2/Fe3O4/CoWO4 (30%) photocatalyst exhibited superior activity. The degradation rate constant for rhodamine B by this ternary nanocomposite was 8.5 and 5.6 folds greater than those of the pure TiO2 and TiO2/Fe3O4 photocatalysts, respectively. Trapping experiments showed that superoxide anion radicals played critical role during the photocatalytic process. Visible-light harvesting due to the presence of CoWO4 and effective suppression of the charge carriers from recombination due to formation of p-n heterojunction are the major parameters affecting the photocatalytic activity. Furthermore, the TiO2/Fe3O4/CoWO4 (30%) photocatalyst displayed highly stable recycling performances. The present study provides a new strategy to design and fabricate magnetically recoverable photocatalysts based on TiO2 with considerable activity under visible-light.