The Dielectric Barrier Discharge plasma (DBD)-catalyst system holds promise for soil decontamination, but catalyst recycling is still challenging. In this study, a MnFe₂O₄ catalyst with recyclability and redox properties was prepared and applied in a DBD system to remove phenanthrene (Phe) from soil. The redox reaction in the MnFe₂O₄ improved the synthesis of reactive oxygen species (ROS), boosting Phe degradation from 80.21 % to 90.21 % within 5 min, with the corresponding kinetic constants was 1.4 and 2.1 times higher than DBD alone. After four recycling cycles, the Phe removal efficiency remained at 88.7 %. Based on the experiment results, the synergistic effect between DBD and MnFe₂O₄ induced oxygen vacancy formation and accelerated redox reactions, favoring the decomposition of O₃ and the degradation of Phe. Furthermore, the Phe degradation pathways were elucidated through the analysis of intermediates in the DBD-MnFe₂O₄ system. This work provides new insight for developing soil remediation systems with environmentally friendly and high efficiency.

中文翻译：

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介电势垒放电等离子体和 MnFe2O4 催化剂增强土壤中有机污染物降解的性能与机理


介电屏障放电等离子体 （DBD） 催化剂系统有望实现土壤净化，但催化剂回收仍然具有挑战性。本研究制备了一种具有可回收性和氧化还原性能的 MnFe₂O₄ 催化剂，并将其应用于 DBD 体系中，以去除土壤中的菲 （Phe）。MnFe₂O₄ 中的氧化还原反应提高了活性氧 （ROS） 的合成，在 5 分钟内将 Phe 降解从 80.21 % 提高到 90.21 %，相应的动力学常数分别是单独使用 DBD 的 1.4 倍和 2.1 倍。经过四个回收循环后，Phe的去除效率保持在 88.7%。基于实验结果，DBD 和 MnFe₂O₄ 之间的协同作用诱导了氧空位的形成并加速了氧化还原反应，有利于 O₃ 的分解和 Phe 的降解。此外，通过分析 DBD-MnFe₂O₄ 系统中的中间体，阐明了 Phe 降解途径。这项工作为开发环境友好、高效的土壤修复系统提供了新的思路。