Prasanna V Lakshmi, Harikaran Dhakshnamoorthi, Avisar Dror, R Vijayaraghavan
Water Research Centre, Hydrochemistry Laboratory Tel Aviv University Ramat - Aviv Tel Aviv 69978 Israel.
Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology Vellore-632 014 India
RSC Adv. 2023 Jan 24;13(6):3416-3424. doi: 10.1039/d2ra05754a.
Inorganic oxide materials such as TiO and ZnO have been extensively studied for environmental remediation, that operates through photo generated Reactive Oxygen Species (ROS) such as HO, ·OH and O to decontaminate waste water. However, inorganic solid oxidants such as metal peroxides capable of generating ROS in aqueous solutions have not been studied for environmental remediation. Towards this objective, we have synthesized peroxides of Zn, Mg, and Ba and characterized these by powder X-ray diffraction, Transmission Electron Microscopy, UV-visible spectroscopy, and X-ray photoelectron spectroscopy. The photocatalytic activity of these wide band gap semiconductors has also been investigated. The novelty of the work is in the use of these peroxides as chemical sources of ROS in aqueous suspensions in addition to their photochemical generation. Hence, these peroxides, in particular Ba, exhibit high photocatalytic activity, better than the well-known ZnO. The mechanisms of ROS generation and subsequent dye degradation are elucidated. ROS has been estimated and is correlated to the photocatalytic activity. This work reports for the first time BaO as potential photocatalyst.
无机氧化物材料如二氧化钛（TiO）和氧化锌（ZnO）已被广泛研究用于环境修复，其通过光生活性氧物种（ROS）如羟基自由基（HO·）、超氧阴离子自由基（·OH）和单线态氧（O）来净化废水。然而，能够在水溶液中产生ROS的无机固体氧化剂如金属过氧化物尚未被研究用于环境修复。为了实现这一目标，我们合成了锌（Zn）、镁（Mg）和钡（Ba）的过氧化物，并通过粉末X射线衍射、透射电子显微镜、紫外可见光谱和X射线光电子能谱对其进行了表征。还研究了这些宽带隙半导体的光催化活性。这项工作的新颖之处在于，除了光化学产生ROS外，还将这些过氧化物用作水悬浮液中ROS的化学来源。因此，这些过氧化物，特别是钡过氧化物，表现出比著名的氧化锌更好的高光催化活性。阐明了ROS的产生机制和随后的染料降解过程。对ROS进行了估算，并将其与光催化活性相关联。这项工作首次报道了过氧化钡作为潜在的光催化剂。
