College of Environment, Hohai University, Nanjing, 210098, PR China.
Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing, 210098, PR China; College of Environment, Hohai University, Nanjing, 210098, PR China.
J Hazard Mater. 2020 Jan 15;382:121064. doi: 10.1016/j.jhazmat.2019.121064. Epub 2019 Aug 21.
The development of non-cobalt-based heterogeneous catalysts with efficient catalytic activity, good stability and nontoxicity is very important for the application of peroxymonosulfate-based advanced oxidation processes (AOPs) in water treatment. In this work, with two dimensional MXene as the catalyst substrate, a novel α-FeO/MXene (FM) nanocomposite was fabricated through a facile solvothermal method. Systematic characterization demonstrated that the MXene substrate could facilitate the size reduction and good dispersion of α-FeO nanoparticles. The FM nanocomposite achieved high efficiency and stability towards activating peroxymonosulfate (PMS) to produce free radicals for the degradation of salicylic acid (SA) in aqueous solution. The operating parameters, including catalyst dosage, PMS dosage, SA concentration and initial pH value, were evaluated and analysed. The co-existence of sulfate radicals (SO) and hydroxyl radicals (OH) was confirmed using electron paramagnetic resonance spectroscopy and radical scavenger tests, while SOwas identified as the main reactive species in the FM/PMS catalytic system. The possible mechanisms for the electron transfer and radical generation during the process of PMS activation by the FM nanocomposite are further investigated using XPS and in situ Raman analysis. The results provide an avenue for rationally constructing and developing alternative catalysts for the treatment of organics in wastewater.
开发具有高效催化活性、良好稳定性和低毒性的非钴基多相催化剂对于过一硫酸盐基高级氧化工艺（AOPs）在水处理中的应用非常重要。在这项工作中，以二维 MXene 作为催化剂基底，通过简便的溶剂热法制备了一种新型的 α-FeO/MXene（FM）纳米复合材料。系统的表征表明，MXene 基底可以促进 α-FeO 纳米颗粒的尺寸减小和良好分散。FM 纳米复合材料在活化过一硫酸盐（PMS）以产生自由基方面表现出高效和稳定性，可用于水溶液中水杨酸（SA）的降解。评估和分析了操作参数，包括催化剂用量、PMS 用量、SA 浓度和初始 pH 值。通过电子顺磁共振波谱和自由基清除剂测试证实了硫酸根自由基（SO）和羟基自由基（OH）的共存，而在 FM/PMS 催化体系中，SO 被确定为主要的反应性物质。进一步通过 XPS 和原位拉曼分析研究了 FM 纳米复合材料活化 PMS 过程中电子转移和自由基生成的可能机制。该结果为合理构建和开发替代催化剂以处理废水中的有机物提供了途径。
