CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science & Technology of China , Hefei, 230026, China.
Environ Sci Technol. 2017 Nov 7;51(21):12611-12618. doi: 10.1021/acs.est.7b03007. Epub 2017 Oct 18.
A high-efficient, low-cost, and eco-friendly catalyst is highly desired to activate peroxides for environmental remediation. Due to the potential synergistic effect between bimetallic oxides' two different metal cations, these oxides exhibit superior performance in the catalytic activation of peroxymonosulfate (PMS). In this work, novel MnFeO nanospheres were synthesized and used to activate PMS for the degradation of bisphenol A (BPA), a typical refractory pollutant. The catalytic performance of the MnFeO nanospheres was substantially greater than that of the Mn/Fe monometallic oxides and remained efficient in a wide pH range from 4 to 10. More importantly, a synergistic effect between solid-state Mn and Fe was identified in control experiments with MnO and FeO. Mn was inferred to be the primary active site in the surface of the MnFeO nanospheres, while Fe(III) was found to play a key role in the synergism with Mn by acting as the main adsorption site for the reaction substrates. Both sulfate and hydroxyl radicals were generated in the PMS activation process. The intermediates of BPA degradation were identified and the degradation pathways were proposed. This work is expected to help to elucidate the rational design and efficient synthesis of bimetallic materials for PMS activation.
一种高效、低成本且环保的催化剂对于激活过氧化物以进行环境修复是非常需要的。由于双金属氧化物的两种不同金属阳离子之间存在潜在的协同效应，因此这些氧化物在过一硫酸盐（PMS）的催化活化中表现出优异的性能。在这项工作中，合成了新型的 MnFeO 纳米球，并将其用于激活 PMS 以降解双酚 A（BPA），这是一种典型的难处理污染物。MnFeO 纳米球的催化性能明显优于 Mn/Fe 单金属氧化物，并且在 pH 值为 4 到 10 的较宽范围内保持高效。更重要的是，在 MnO 和 FeO 的对照实验中，发现了固态 Mn 和 Fe 之间的协同效应。推断 Mn 是 MnFeO 纳米球表面的主要活性位，而 Fe(III) 则通过充当反应底物的主要吸附位，在协同作用中发挥关键作用。在 PMS 活化过程中同时生成了硫酸盐和羟基自由基。鉴定了 BPA 降解的中间产物，并提出了降解途径。这项工作有望有助于阐明用于 PMS 激活的双金属材料的合理设计和高效合成。
