Insight into the enhanced catalytic activity of a red mud based Fe2O3/Zn–Al layered double hydroxide in the photo-Fenton reaction. Issue 21 (22nd September 2020)

• Record Type: Journal Article
• Authors: Li, Qingyong; Wei, Guangtao; Yang, Yanjuan; Li, Zhongmin; Zhang, Linye; Shao, Luhua; Lai, Shiting
• Is Part Of: Catalysis science & technology. Volume 10:Issue 21(2020)
• Page Start: 7365
• Page End: 7377
• Publication Date: 2020-09-22
• Subjects: Catalysis -- Periodicals; 541.395
• DOI: 10.1039/d0cy01539c
• Languages: English
• ISSNs: 2044-4753

Abstract

Abstract : In this work, the enhanced catalytic activity of red mud based Fe2 O3 /Zn–Al layered double hydroxide in the photo-Fenton reaction has been studied in detail. Abstract : In this work, the catalytic activity of an Fe2 O3 /Zn–Al layered double hydroxide (F/ZA-LDH) in the photo-Fenton reaction has been studied in detail. The F/ZA-LDH composite exhibited significantly enhanced catalytic activity in a photo-Fenton system. The apparent rate constant of F/ZA-LDH in the photo-Fenton reaction was about 4 times higher than that of the pure Zn–Al LDH, and was about 10 times higher than that of the red mud, which was the main material for synthesized F/ZA-LDH. It was found that besides the increased surface area (45.64 m 3 g −1 ) and enhanced pore volume of the F/ZA-LDH composite, the suitable concentration of oxygen vacancies could account for the significantly enhanced catalytic activity of F/ZA-LDH. The oxygen vacancies favor the visible light absorption and the efficient charge separation and transfer of F/ZA-LDH. Moreover, density functional theory (DFT) calculations were used to explore the electronic structures of the as-prepared samples, and the photocatalytic activity of F/ZA-LDH was also analyzed based on the results of electronic structures. The F/ZA-LDH composite exhibited excellent settleability, good reusability and stability in use. Finally, the possible mechanisms involved in the photo-Fenton system catalyzed by F/ZA-LDH have been proposed. This work would provide a systematic understanding of the high catalytic activity of the Fe2 O3 /Zn–Al layered double hydroxide which has been prepared using bulk waste red mud as the main material via mechanochemical synthesis.