ZnO–Al2O3–CeO2–Ce2O3 mixed metal oxides as a promising photocatalyst for methyl orange photocatalytic degradation. (August 2021)

• Record Type: Journal Article
• Authors: Janani, F.Z.; Khiar, H.; Taoufik, N.; Elhalil, A.; Sadiq, M.; Puga, A.V.; Mansouri, S.; Barka, N.
• Is Part Of: Materials today chemistry. Volume 21(2021)
• Publication Date: 2021-08
• Subjects: Environmental remediation -- Photocatalysis -- Electron-hole separation -- Photostability -- Reusability; Chemistry -- Periodicals; Materials -- Research -- Periodicals; Materials science -- Periodicals; Chemistry; Materials -- Research; Electronic journals; Periodicals; 660.282
• DOI: 10.1016/j.mtchem.2021.100495
• Languages: English
• ISSNs: 2468-5194

Abstract

Abstract: In this research article, ZnO–Al2 O3 –CeO2 –Ce2 O3 mixed metal oxides phases were prepared by calcination of Zn–Al/Ce–CO3 layered double hydroxides (LDH) precursors, and evaluated for the photocatalytic degradation of methyl orange (MO) as a model textile dye from aqueous solution under UV irradiation. First, Zn–Al–CO3 and a series of Zn–Al/Ce–CO3 with different Ce content (5, 10, 15, 20%) were synthesized through co-precipitation method at Zn/(Al+Ce) molar ratio (r) of 3, then subjected to calcination at 500 °C for 6 h. Samples were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy coupled with energy dispersive X-ray analysis and pH point of zero charge. The experimental results of the photodegradation reveal that the photocatalyst developed from Zn–Al–Ce10%-CO3 LDH exhibits the highest photocatalytic activity, with a degradation efficiency of 99.8% after 300 min of irradiation. This performance was mainly ascribed to the presence of difference state of Ce, leading a highest separation efficiency of electrons and holes. The recycling tests suggests a much high photostability and reusability of the photocatalyst. Highlights: ZnO–Al2 O3– CeO2– Ce2 O3 mixed oxides derived from Zn-Al/Ce layered double hydroxides. Catalyst with 10% Ce content exhibits an excellent efficiency of 99.8% for 40 mg/L of MO solution 20 mg/L of catalyst. The presence of different state of Ce, leading to enhanced separation of electron-hole pairs on the surface of catalyst. Recycling tests suggest a much high photostability and reusability of the photocatalyst.