Preparation and photo-fenton degradation activity of α-Fe2O3 nanorings obtained by adding H2PO4−, SO42−, and citric acid

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2020-02, Vol.382, p.123010, Article 123010
• Main Authors: Liu, Huating, Tong, Mengli, Zhu, Kaili, Liu, Hui, Chen, Rufen
• Format: Article
• Language: English
• Subjects: Citric acid; H2PO4; Photocatalytic activity; SO42; α-Fe2O3 nanoring
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2019.123010

[Display omitted] •The small-sized α-Fe2O3 nanorings were prepared by adding H2PO4−, SO42− and citric acid.•The obtained α-Fe2O3 nanorings showed high surface area and surface-bound Fe(II) content.•The prepared α-Fe2O3 nanorings exhibited excellent photocatalytic activity toward PNP degradation. Improving the photocatalytic activity of α-Fe2O3 is crucial for the photo-Fenton degradation of organic pollutants. Herein, high-activity α-Fe2O3 nanorings were prepared via hydrothermal synthesis by adding H2PO4, SO42−, and citric acid. Analysis showed that spindle-shaped α-Fe2O3 particles were formed when only NaH2PO4 was added. Spindle-shaped α-Fe2O3 was dissolved along the c-axis to form hollow-structured products due to the coordination of SO42−. Small-sized citric acid-modified α-Fe2O3 nanorings with outer and inner diameters of approximately 60 nm and 30 nm, respectively, were obtained by adding a small amount of citric acid under the synergy of H2PO4−, SO42−, and citric acid. The as-prepared α-Fe2O3 nanorings with a high surface area can enhance visible light absorption, inhibit photo-induced electron and hole recombination, and increase surface-bound Fe(II) content. Consequently, catalytic activity in the photo-Fenton degradation of p-nitrophenol was increased.