Interaction of mackinawite (FeS) with O₂ has attracted much attention recently for contaminant transformation due to reactive oxidant production. However, the effect of in situ generated Fe (oxyhydr)oxide coatings on FeS reactivity and the resultant reactive oxidant production remains poorly understood. To clarify this effect, we specially prepared partially oxidized FeS with in situ generated Fe (oxyhydr)oxide coatings, and then stored it in the anoxic environment to explore the interactions between FeS and Fe (oxyhydr)oxide coatings, and characterized the variation of morphology and Fe(II) species by STEM, XRD, Mössbauer spectroscopy and XPS. We found that the reactivity of FeS upon oxygenation and the resultant •OH production for phenol oxidation were prominently accelerated after anoxic settling. XRD patterns exhibited the formation of more crystalline Fe (oxyhydr)oxide coatings, Mössbauer spectra identified the generation of a new Fe(II) species, and XPS results revealed the increase in Fe(II) fraction on the surface during anoxic settling. These variations were most probably attributed to the electron transfer between FeS core and Fe (oxyhydr)oxide coatings driven by the redox potential gradient. Our findings deepened the mechanistic understanding of FeS reactivity and the resultant oxidizing impact on contaminant transformation under O₂-perturbed conditions.

由于反应性氧化剂的产生，近年来，麦基钠铁矿（FeS）与O _2的相互作用引起了污染物转化的广泛关注。然而，对原位生成的Fe（羟基氧化物）涂层对FeS反应性和所产生的反应性氧化剂产生的影响的了解仍然很少。为了阐明这种效果，我们专门制备了原位部分氧化的FeS生成Fe（OH）氧化物涂层，然后将其存储在缺氧环境中以探索FeS和Fe（OH）氧化物涂层之间的相互作用，并通过STEM，XRD，Mössbauer光谱和XPS。我们发现，缺氧沉​​降后，FeS在氧化时的反应性和生成的用于酚氧化的•OH生成显着加快。XRD图谱显示形成了更多结晶的Fe（OH）涂层，Mössbauer光谱确定了新的Fe（II）物种的产生，XPS结果表明在缺氧沉降过程中表面Fe（II）分数的增加。这些变化最有可能归因于由氧化还原电势梯度驱动的FeS核与Fe（羟基氧化物）涂层之间的电子转移。_2-摄动条件。