Fe-Species-Loaded Mesoporous MnO2 Superstructural Requirements for Enhanced Catalysis
Fe-Species-Loaded Mesoporous MnO2 Superstructural Requirements for Enhanced Catalysis
复制标题
负载 Fe 物质的介孔 MnO2 增强催化的超结构要求
DOI：
10.1021/am505989j
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发表时间：
2015-02-25
影响因子：
9.5
通讯作者：
Lai, Joseph K. L.
中科院分区：
文献类型：
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作者：
Huang, Ruting;Liu, Yanyu;Lai, Joseph K. L.
在这项工作中，一种新型催化剂，即负载铁的介孔二氧化锰（Fe/M-MnO2）海胆状超结构，已通过两步技术成功制备。首先，介孔二氧化锰 (M-MnO2) 海胆状超结构：通过简单的方法在 CH2Cl2 和 H2O 之间的软界面上合成，无需模板。然后通过湿法浸渍、焙烧得到M-MnO2固定氧化铁催化剂。微观结构分析表明，M-MnO2 由具有丰富介孔性的纳米棒构件组装而成的海胆状空心亚微球组成。 Fe/M-MnO2 保留了空心亚微球，其上覆盖有破碎和缩短的 MnO2 纳米棒的杂化复合材料。能量色散 X 射线微量分析用于确定 Fe 负载过程的可用性以及 Fe/M-MnO2 中 Fe 的均匀性。评价了 M-MnO2 和 Fe/M-MnO2 在催化湿式过氧化氢氧化亚甲基蓝（MB）（印染废水中典型有机污染物）中的催化性能。当使用 Fe/M-MnO2 催化剂时，催化降解显示出高效的 MB 变色，例如约 100%。当反应进行120分钟时，94.8%的MB被分解。通过铁浸出试验和重复使用实验证实了该 Fe/M-MnO2 催化剂在反应介质中的卓越稳定性。机理分析表明，羟基树自由基负责MB的去除，并由M-MnO2和Fe/M-MnO2催化。 MB转化为小有机化合物，然后进一步降解为CO2和H2O。本研究获得的新见解将有利于多相催化剂在废水处理中的实际应用。
In this work, a novel catalyst, Fe-species-loaded mesoporous Manganese dioxide (Fe/M-MnO2) urchinlike superstructures, has been fabricated successfully in a two-step technique. First,, mesoporous manganese dioxide (M-MnO2) urchinlike superstructures: have been synthesized by a facile method on a soft interface between CH2Cl2 and H2O without templates. Then the M-MnO2-immobilized iron oxide catalyst was obtained through wetness impregnation and calcination. Microstructural analysis indicated that the M-MnO2 was composed of urchinlike hollow submicrospheres assembled by nanorod building blocks with rich mesoporosity. The Fe/M-MnO2 retained the hollow submicrospheres, which were covered by hybridized composites with broken and shortened MnO2 nanorods. Energy-dispersive X-ray microanalysis was used to determine the availability of Fe loading processes and the homogeneity of Fe in Fe/M-MnO2. Catalytic performances of the M-MnO2 and Fe/M-MnO2 were evaluated in catalytic wet hydrogen peroxide oxidation of methylene blue (MB), a typical organic pollutant in dyeing wastewater. The catalytic degradation displayed highly efficient discoloration of MB when using the Fe/M-MnO2 catalyst, e.g., ca. 94.8% of MB was decomposed when the reaction was conducted for 120 min. The remarkable stability of this Fe/M-MnO2 catalyst in the reaction medium was confirmed by an iron leaching test and reuse experiments. Mechanism analysis revealed that the hydroxyl Tree radical was responsible for the removal of MB and catalyzed by M-MnO2 and Fe/M-MnO2. MB was transformed into Small organic compounds and then further degraded into CO2 and H2O. The new insights obtained in this study will be beneficial for the practical applications of heterogeneous catalysts in wastewater treatments.