Er3+-doped ZnO/ZnAl2O4 multi-phase oxides acting as near-infrared active photocatalyst
- 79 Downloads
Doping lanthanide ions in metal oxides is an efficient way to develop visible and near-infrared (NIR) active photocatalysts. Herein, we present a method to develop NIR active photocatalyst via doping Er3+ into ZnO/ZnAl2O4 multi-phase oxides by isomorphous replacement of Al3+ with Er3+ during the preparation of Zn/Al-hydrotalcite-like compound, specifically, the calcination of the hydrotalcite-like compound at 900 °C. The as-prepared Er3+-doped catalyst and its precursor were characterized using X-ray diffraction technique, scanning electron microscopy, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy and near-infrared-visible-ultraviolet diffused reflectance spectroscopy. It was found that the doping of Er3+ causes lattice expansion for ZnO and ZnAl2O4, and yields optical absorptions at visible and NIR light regions. The obtained Er3+-doped ZnO/ZnAl2O4 multi-phase oxides produce superoxide and hydroxyl radicals in the photocatalytic process, and show enhanced ultraviolet (UV) photocatalytic activity on degradation of methyl orange, compared to undoped ZnO/ZnAl2O4 multi-phase oxides. The Er3+-doped ZnO/ZnAl2O4 multi-phase oxides also possess visible and NIR light photocatalytic activities, and its photocatalytic activity is rather stable under UV, visible and NIR light irradiation. This work provides a new way for doping of lanthanide ions in metal oxides and designing full-spectrum photocatalysts.
The project was funded by the National Natural Science Foundation of China (Grant No. 31270625). The authors thank Mr. Ruoyu Liu from Reed College for his thorough English revision and academic discussion on the manuscript. Dr. Haidong Li from Qingdao University is acknowledged for his help in XPS analysis.
Compliance with ethical standards
Conflict of interest
There is no conflict of interest.
- 2.Z. Aghajani, A.A. Engashte-Vahed, M.R. Zand-Monfared, J. Mater. Sci.: Mater. Electron. 28, 17338 (2017)Google Scholar
- 3.K. Nithiyadevi, K. Ravichandran, J. Mater. Sci.: Mater. Electron. 28, 10929 (2017)Google Scholar
- 4.Y. Tang, W. Di, X. Zhai, R. Yang, W. Qin, ACS Catal. 3, 406 (2013)Google Scholar
- 40.J.C. Barreto, G.S. Smith, N.H.P. Strobel, P.A. McQuillin, T.A. Miller, Life Sci. 56, 89 (1995)Google Scholar
- 43.V. Nguyen, T.K.C. Tran, D.V. Nguyen, Adv. Nat. Sci.: Nanosci. Nanotechnol. 2, 045011 (2011)Google Scholar