School of Ecological & Environmental Science, Shanghai Key Laboratory for Urban Ecological Process and Eco-Restoration, East China Normal University, Shanghai 200241, China; Institute of Eco-Chongming, Shanghai 200062, China.
School of Environmental Science and Engineering, Tongji University, Shanghai 200071, China.
Chemosphere. 2019 Mar;218:83-92. doi: 10.1016/j.chemosphere.2018.11.098. Epub 2018 Nov 16.
To enhance the catalytic and separation properties of akaganéite nanoparticles, rice spike-like akaganéite impregnated graphene oxide (β-FeOOH@GO) nanocomposite was fabricated through facile hydrolysis. The apparent first-order decolorization rate of methylene blue (MB) in β-FeOOH@GO catalyzed photo Fenton-like system was 0.6322 min about 3 folds that of prinstine β-FeOOH nanoparticles. The degradation intermediates of MB adsorbed on the solid surface of β-FeOOH@GO were comprehensively identified with time of flight-secondary ion mass spectroscopy (TOF-SIMS) for the first time. Newly identified sulfoxide intermediates, sulphone intermediates and desulfurization intermediates and N-demethylaton or dedimethamine intermediates were reported for the first time. The proposed degradation pathway of MB predominantly proceeded with the rupture of phenothiazine rings oxided with OH, and singlet oxygen (O) radicals, which fully extending the reaction pathways proposed in previous work in literature. The enhanced catalytic activity of β-FeOOH@GO was ascribed to the formation of heterojunctions confirmed by the presence of FeOC chemical bonds through X-ray photoelectron spectroscopy (XPS). The complete elimination of MB and its acute toxicity to Luminous bacteria showed that β-FeOOH@GO would be served as a highly efficient Fenton-like catalyst for treatment of high concentration refractory organic contaminant.
为了提高纤铁矿纳米粒子的催化和分离性能，通过简便的水解制备了稻穗状纤铁矿负载氧化石墨烯（β-FeOOH@GO）纳米复合材料。在β-FeOOH@GO 催化类芬顿光降解体系中，亚甲基蓝（MB）的表观一级脱色速率约为 0.6322 min-1，是原始β-FeOOH 纳米粒子的 3 倍。首次利用飞行时间二次离子质谱（TOF-SIMS）全面鉴定了吸附在β-FeOOH@GO 固体表面上的 MB 降解中间体。首次报道了新鉴定的亚砜中间体、砜中间体和脱硫中间体以及 N-去甲基化或去二甲胺中间体。MB 的拟议降解途径主要是通过 OH 和单线态氧（O）自由基氧化苯并噻嗪环断裂进行的，这充分扩展了文献中以前工作提出的反应途径。β-FeOOH@GO 的增强催化活性归因于通过 X 射线光电子能谱（XPS）存在 FeOC 化学键证实的异质结的形成。MB 的完全消除及其对发光菌的急性毒性表明，β-FeOOH@GO 将作为一种高效的类芬顿催化剂，用于处理高浓度难处理的有机污染物。
