Key Lab of Groundwater Resources and Environment, Ministry of Education, Jilin University, Changchun, 130026, PR China; Jilin Provincial Key Laboratory of Water Resources and Environment, Jilin University, Changchun, 130026, PR China.
Key Lab of Groundwater Resources and Environment, Ministry of Education, Jilin University, Changchun, 130026, PR China; Jilin Provincial Key Laboratory of Water Resources and Environment, Jilin University, Changchun, 130026, PR China.
Chemosphere. 2020 Sep;255:126961. doi: 10.1016/j.chemosphere.2020.126961. Epub 2020 May 6.
Sulfate radical-based advanced oxidation processes (SR-AOPs) have received increasing attention as viable technology for recalcitrant organics removal from polluted waters. As for heterogeneous catalyst, it is crucial to reveal the effect of morphology on its catalytic activity and mechanism, providing guidelines for rational design of morphology-dependent catalysts. Hence, in this study, we selected manganese oxyhydroxide (MnOOH) as the peroxymonosulfate (PMS) activator and synthesized different morphological MnOOH with the same crystal structure. The catalytic activity of MnOOH follows: nanowires > multi-branches > nanorods. Different morphological MnOOH had different physical and chemical characterization such as specific surface area, Lewis sites, ζ-potential and redox potential, which played positive roles in catalytic activity of MnOOH as PMS activator. Unexpectedly, it was found that ζ-potential was more crucial than specific surface area, redox potential and Lewis sites. Notably, nanowires exhibited higher positive zeta potential, which was favor of promoting interfacial reactivity between HSO and surface of MnOOH. Furthermore, •OH, SO•, O• and O, were involved in the MnOOH/PMS system. Moreover, the cycle of Mn (III)/Mn (II) accelerated MnOH formation. This study provided a new understanding of manganese-catalyzed peroxymonosulfate activation and elucidated the relationships between morphology of catalyst and its catalytic activity.
基于硫酸盐自由基的高级氧化工艺（SR-AOPs）作为一种从受污染水中去除难降解有机物的可行技术，受到了越来越多的关注。对于多相催化剂来说，揭示形态对其催化活性和机理的影响至关重要，为基于形态的催化剂的合理设计提供了指导。因此，在本研究中，我们选择了水合氧化锰（MnOOH）作为过一硫酸盐（PMS）的活化剂，并合成了具有相同晶体结构的不同形态的 MnOOH。MnOOH 的催化活性遵循：纳米线＞多分支＞纳米棒。不同形态的 MnOOH 具有不同的物理化学特性，如比表面积、路易斯位、ζ-电位和氧化还原电位，这些特性对 MnOOH 作为 PMS 活化剂的催化活性起着积极的作用。出乎意料的是，我们发现ζ-电位比比表面积、氧化还原电位和路易斯位更为重要。值得注意的是，纳米线表现出更高的正 ζ-电位，这有利于促进 HSO 和 MnOOH 表面之间的界面反应。此外，•OH、SO•、O•和 O2-都参与了 MnOOH/PMS 体系。此外，Mn（III）/Mn（II）的循环加速了 MnOH 的形成。本研究为锰催化过一硫酸盐活化提供了新的认识，并阐明了催化剂形态与其催化活性之间的关系。
